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Research Article

Computational approach in obtaining analytic solutions of a generalized nonlinear breaking soliton equation with applications in engineering and physics

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Article: 2331984 | Received 29 Mar 2023, Accepted 11 Mar 2024, Published online: 27 Mar 2024

Abstract

Higher-order nonlinear wave models have been a source of attraction to a huge number of researchers in recent times as a result of their significance in mathematical physics, other nonlinear sciences as well as engineering. In consequence, we outline in this paper the analytical studies entrenched on a generalized structure of a nonlinear breaking soliton equation with higher-order nonlinearity in four variables which have applications in science as well as engineering. Lie group theory is utilized to generate an 11-dimensional Lie algebra associated with the equation under consideration and in addition one parametric group of transformations related to the algebra is calculated. Besides, the technique is further invoked in performing reductions of the various subalgebras of the understudy model. Moreover, in conjunction with the theory, the direct integration technique is engaged to secure an analytic solution of the equation and as a result, a general analytic solution with regard to the second-kind elliptic-integral function is furnished. Moreover, we engage the novel simplest equation technique to gain more general solutions to the equation. In consequence, solitonic solutions comprising periodic, dark-bright, topological kink as well as singular solutions are achieved. We complemented that by exhibiting the dynamics of the secured solutions with the aid of graphical representations. In conclusion, we calculate conserved quantities associated with the aforementioned equation by invoking the well-celebrated classical Noether theorem technique.

1. Introduction

It has been understood that nonlinear phenomena to a large extent possess an expansive scale in diverse arms of applications of mathematical physics as well as engineering. Nonlinearity is such an enthralling concept of the universe that countless scientists have contemplated nonlinear science virtually as a highly essential edge to aid the cardinal knowledge of the earth. Mathematical modelling of phenomena which are intricate and also change with time is dependent intensely on the study of a distinctive class of nonlinear ordinary differential equations (NLODEs) as well as nonlinear partial differential equations (NLPDEs). For instance, the femto-second optical pulses embedded in a double-refractive optical fibre, modelled into an NLPDE, were investigated in [Citation1], the vector bright solitons, alongside their various interaction attribute related to the coupled Fokas–Lenells system were also studied. Recently, the authors in [Citation2] examined a (3 + 1)-D nonlinear generalized type of potential Yu–Toda–Sasa–Fukuyama model existent in physics alongside engineering. These models have been introduced in highly unalike fields of study which range from the physical along with natural sciences, neural networks, infectious disease epidemiology, population ecology to economics, plasma physics, elasticity, optical fibres and fluid mechanics alongside solid-state physics. See more in [Citation3–18].

Sophus Lie (1842–1899) with his quintessential work on Lie Algebras [Citation19,Citation20] which is essentially a unified approach for the treatment of a wide class of differential equations (DEs). With the inspiration of Galois theory, Sophus Lie, a Norwegian mathematician, established symmetry methods and demonstrated that many of the known ad-hoc methods of integration of DEs could be obtained in a systematic manner. The approach has evolved into a helpful tool for solving DEs, classifying them and preserving the solution set. In addition, we state that Lie group analysis furnishes a universal and robust approach through which tough nonlinear differential equations can be solved, once the symmetries are available which happens in most cases. This makes the technique stand out and performs much better than any other method.

Furthermore, it has been observed that conservation laws are established and entrenched natural laws that have been studied by many researchers in various scientific fields. Conservation laws that are commonly used in this context include conservation of linear momentum in an isolated system, conservation of electric charge, conservation of energy, conservation of mechanical energy in the absence of dissipative forces and many others. Conservation laws are deliberated to be basic laws of nature, with extensive application in physics and numerous other fields. Some of the importance of conservation laws include [Citation21]:

  1. the stability analysis and the global behaviour of solutions,

  2. the development of numerical methods and provide an essential starting point for finding potential variables and nonlocally related systems,

  3. the investigation of integrability and linearization mappings.

Closed-form solitary wave solutions provide us with better information about physical phenomena. Hence, substantial efforts have been devoted by several physical scientists as well as mathematicians to establish robust techniques in securing analytical along with numerical outcomes for NLPDEs.

Stating a few of the established techniques, we have extended homoclinic-test approach [Citation22], generalized unified technique [Citation23], tanh–coth technique [Citation24], Bäcklund transformation approach [Citation25], Cole–Hopf transformation approach [Citation26], Painlevé expansion approach [Citation27], Adomian decomposition method [Citation28], mapping, as well as extended mapping approach [Citation29], homotopy perturbation approach [Citation30], rational expansion method [Citation31], simplest as well as extended simplest equation [Citation32], F-expansion approach [Citation33], Hirota technique [Citation34], Lie point symmetry analysis [Citation19,Citation20], the (GG)-expansion approach [Citation35], Darboux transformation technique [Citation36], sine-Gordon equation expansion approach [Citation37], exponential function technique [Citation38], Kudryashov's technique [Citation39], tanh-function method [Citation40], bifurcation approach [Citation41] and the like.

Nonetheless, nonlinear task gives rise to some basic defiances that are readily problematic to check, due to nonlinear traits of the system distinctly transforming as a result of a negligible switch of valid-time-inclusive parameters. Consequently, the situation becomes more bewildering, which demands a paramount solution.

The breaking soliton system (BSS)[Citation42] is expressed as (1) pt+αpxxy+4αpqx+4αpxq=0,(1) (2) pyqx=0,(2) where constant parameter α0 was first established by Bogoyavlensky [Citation42]. BSS (Equation1) portrays the existence of interaction of a long wave in regard to x-axis alongside a Riemann-wave propagating directly toward the y-axis. This fact was first described in 1977 by Degasperis and Calogero. Li et al. [Citation43] engaged in an infinitesimal version of the dressing technique to construct diverse symmetries for BSS via Lie algebra. Moreover in [Citation44], Zheng together with Zhang prepared some transformations and also went ahead to extend the generalized projective Riccati equation technique initiated in [Citation45]. Besides the authors applied these approaches to BSS (Equation1) which made them recover six types of new distinctive exact solution-like results. Painlevé property, as well as the secured dromion-like structures for system (Equation1), was proven by Lakshmanan together with Radaha [Citation46]. Furthermore, a general variable separation solution of BSS (Equation1) was achieved by Zhang et al. [Citation47]. Darvishi and Najafi [Citation48] compute some explicit closed-form solutions of (Equation1) through the concept of a three-wave-solution approach via Maple software. In [Citation49], the authors found the analytic breather cross-kink solution for BSS (Equation1) by utilizing Hirota bilinear technique. In the same vein, Chen et al. [Citation50] invoke the (G/G)-expansion technique to gain new general but non-travelling wave solutions for the system under investigation. Chaotic solitons, in conjunction with various annihilation solitons, were secured via the improved mapping technique in [Citation51]. Moreso, periodic-type soliton, breather-type solitonic outcome and two-solitonic solutions alongside three-soliton solutions concerning BSS (Equation1) were gained by utilizing the extended three-wave approach in [Citation52]. In [Citation53], multi-soliton solutions via the Wronskian approach as well as Hirota bilinear technique were invoked, as a result, double Wronskian solution and N-soliton solutions were gained by the authors. Li in [Citation54] derived doubly periodic wave solutions along with diverse of the breather-type solitary-wave solutions for system (Equation1) by virtue of generalized three-wave approach with Hirota bilinear technique. Various structures of analytical solutions of BSS (Equation1) were achieved through the Darboux transformation along with mapping techniques in [Citation55]. Hossein et al. in [Citation56] employed the particular auxiliary function alongside Hirota bilinear approach to achieve solitary waves together with rogue wave solutions for BSS (Equation1). Curved solitons, dromion, lumps and breathers together with ring solitons solutions of BSS (Equation1) via Bäcklund transformations were achieved by Ruan in [Citation57]. In [Citation58], the authors on the basis of the singular manifold technique attained the periodic wave results of BSS (Equation1) with regard to Jacobi elliptic functions. Additionally, the similarity transformation approach based on the Lie group technique was investigated in constructing analytic solutions of BSS (Equation1). Besides, in [Citation59], the authors gained quadratic, periodic, multi-solitons with asymptotic solutions to BSS (Equation1).

Two-dimensional breaking soliton equation [Citation60] is stated as (3) uxt4uxuxy2uxxuyuxxxy=0.(3) Diverse families of solutions have been achieved in the literature for model (Equation3) existing in dimensions of two [Citation60–62] that delineate the interconnections that are existing between the longwave alongside Riemann wave propagating respectively along x with y-axes.

Nonlinear three-dimensional breaking soliton model (3D BSM) [Citation63] that reads (4) uxxxy+uxxxzuxt+4uxuxy+4uxuxz+2uyuxx+2uzuxx=0,(4) with u=u(t,x,y,z):Rt×Rx×Ry×RzR.

Nonlinear 3D BSM (Equation4) has been at the forefront of study by a good number of researchers. Demiray et al. [Citation63] secured an approximate solution of the equation by invoking the perturbed homotopy technique. Besides, the authors formed a chart that comprises numerical results and concluded by presenting the graphics of the secured solution. In [Citation64], some classical solutions of nonlinear 3D BSM (Equation4) were gained after Hirota's bilinear structure was formed. Also, the authors revealed that the three-wave technique is easy to achieve solutions of nonlinear partial differentiation. Residual symmetries of (Equation4) were obtained in [Citation65]. The authors went further to prove that Equation (Equation4) is integrable due to it possessing a Riccati expansion persistently. Tariq et al. [Citation66] secured some travelling wave solutions of (Equation4) where they observed that the outcome held key importance in explicating physical situations. Furthermore, Pallavi et al. [Citation67] gained some analytical solutions of a version of (Equation4) via the engagement of extended-exp(ϕ(ξ)) -expansion technique. Al-Amr [Citation68] obtained closed-form solutions of a different version of (Equation4) when u is not depending on t through the use of a modified simple equation technique. In [Citation69], Xu et al. investigated the bidirectional solitons, integrability characteristics as well as localized solutions of a version of (Equation4). The authors performed a singularity manifold analysis of the equation and achieved a new model which existed in the sense of Painlevé condition. Additionally, localized excitations, periodic, lump and solitary waves, as well as multi-dromion solutions, were gained. Having explicated various research works carried out on 3D BSM (Equation4), we go ahead to generalize the equation in the subsequent part of the work. For the first time, we carry out a detailed investigation in performing a Lie group analysis on the generalized version. Besides, for the very first time, we secure various Noether's symmetry of the generalized version and utilize them to obtain abundant conserved vectors of the equation and all these portray the novelty of our research work.

1.1. Governing equation

In this research, we contemplate investigating a generalized nonlinear (3 + 1)-D breaking soliton equation (3D-genBSMe) stated as (5) αuxxxy+βuxxxzγuxt+2θuxuxy+2θuxuxz+θuyuxx+θuzuxx=0,(5) with parameters θ, α, β, γ regarded as real value constants which are nonzero. We recover the generalized version (Equation5) from the earlier-presented model (Equation4), if we assume θ=2, and α=β=γ=1.

Having earlier explicated the originality/novelty of the work in this paper, the research paper is thus arranged in the following structure, viz. Section 1 furnishes the introduction alongside the literature of the understudy model. In Section 2, the implementation of Lie group analysis of 3D-genBSMe (Equation5) is achieved, and we compute various groups of transformations corresponding to the obtained results. Besides, Lie point symmetries of (Equation5) are implored in performing reductions on the equation. Section 3 employs the simplest equation technique to gain exact solutions of (Equation5). The discussion of results alongside their pictorial representations is done in Section 4. Moreover, we present in Section 5, the conservation laws ascribed to the underlying model by utilizing the conserved-vector theorem by Noether. Finally, concluding remarks are presented afterwards.

2. Lie group analysis of (eqn5)

One first presents the step-by-step way of computing the Lie point symmetries of 3D-genBSMe (Equation5) which at the end will be used in the construction of exact solutions of (Equation5).

2.1. Lie point symmetries of 3D-genBSMe (5)

We examine the Lie algebra with an infinitesimal dimension that is spanned via the vector fields explicated as P=ξ1(t,x,y,z,u)t+ξ2(t,x,y,z,u)x+ξ3(t,x,y,z,u)y+ξ4(t,x,y,z,u)z+η(t,x,y,z,u)u, with the vector field giving the required symmetries of 3D-genBSMe (Equation5) and P satisfying the invariance criteria (6) P[4][αuxxxy+βuxxxzγuxt+2θuxuxy+2θuxuxz+θuyuxx+θuzuxx]=0,(6) whenever γuxt+2θuxuxy+2θuxuxz+θuyuxx+θuzuxx+αuxxxy+βuxxxz=0, where P[4] connotes the extension of P. Corresponding formula for P[4] reads (7) P[4]=P+ηtut+ηxux+ηyuy+ηzuz+ηtxutx+ηxxuxx+ηxyuxy+ηxzuxz+ηxxxyuxxxy+ηxxxzuxxxz.(7) The application of P[4] to model (Equation5) occasions the invariant conditions expressed as (8) γηxt+2θ(ηxuxy+uxηxy+ηxuxz+uxηxz)+θ(ηxxuy+uxxηy+ηxxuz+uxxηz)+αηxxxy+βηxxxz=0,(8) with the coefficients of P[4], that is, ηx, ηy, ηz, ηxt, ηxx, ηxy, ηxz, ηxxxy as well as ηxxxz given as (9) ηt=Dt(η)utDt(ξ1)uxDt(ξ2)uyDt(ξ3)uzDt(ξ4),ηx=Dx(η)utDx(ξ1)uxDx(ξ2)uyDx(ξ3)uzDx(ξ4),ηy=Dy(η)utDy(ξ1)uxDy(ξ2)uyDy(ξ3)uzDy(ξ4),ηz=Dz(η)utDz(ξ1)uxDz(ξ2)uyDz(ξ3)uzDz(ξ4),ηtx=Dx(ηt)uttDx(ξ1)utxDx(ξ2)uytDx(ξ3)uztDx(ξ4),ηxx=Dx(ηx)utxDx(ξ1)uxxDx(ξ2)uxyDx(ξ3)uxzDx(ξ4),ηxy=Dx(ηy)uytDx(ξ1)uxyDx(ξ2)uyyDx(ξ3)uzyDx(ξ4),ηxz=Dx(ηz)uztDx(ξ1)uxzDx(ξ2)uzyDx(ξ3)uzzDx(ξ4),ηxxxy=Dx(ηxxy)uxxytDx(ξ1)uxxxyDx(ξ2)uxxyyDx(ξ3)uzyxxDx(ξ4),ηxxxz=Dx(ηxxz)utxxzDx(ξ1)uxxxzDx(ξ2)uzyxxDx(ξ3)uzzxxDx(ξ4).(9) (See the detailed expansion of the coefficients (Equation9) in the appendix.) We have the total derivatives (Dt, Dx, Dy, Dz) expressed as [Citation20] (10) Dt=t+utu+uttut+uytuy+.Dx=x+uxu+uxxux+uxtut+,Dy=y+uyu+uyyuy+uytut+,Dz=z+uzu+uzzuz+uztut+.(10) Applying Equation (Equation9) in (Equation8), we equate the resulting differential coefficients of u together with its diverse derivatives to zero. Later, we solve the determining equations and secure system ξx1=0,ξx3=0,ξx4=0,ξy1=0,ξy2=0,ξz1=0,ξz2=0,ξu1=0,ξu2=0,ξu3=0,ξuz=0,ηtx=0,ηut=0,ηxx=0,ηxy=0,ηxz=0,ξzz4=0,ξzz3=0,ηuy=0,ηux=0,ηyyηzz=0,ηyz+ηzz=0,ηuz=0ηuu=0γξt2+θ(ηy+ηz)=0,γξt3+2θηx=0,γξt4+2θηx=0,αξy4+βξz3=0,αξy3αξz4+αξz3+βξz3=0,αξx2+αηuαξz3+βξz3=0,αξt1+2αηuαξz4+2βξz3αξz3=0. In solving the 31 system of equations, the result furnishes infinitesimal generators of one-parameter Lie symmetries of (Equation5) as ξ1=(2c2+2c3+c4)t+c8αβc3t,ξ2=2θγG3(t)c2xαβc3x+c3x+c7,ξ3=αβc3z2θγc1t+αβc3y+c3y+c4y+c6,ξ4=2θγc1t+c3y+c4z+c5,η=c1x+c2u+(y+z)G3(t)+G1(t)+G2(t,zy). Hence, we secure 11-dimensional Lie algebra ascribed to infinitesimal symmetries of 3D-genBSMe (Equation5) spanned via the vector fields, namely: (11) P1=t,P2=x,P3=y,P4=z,P5=G1(t)u,P6=G(t,zy)u,P7=uu2ttxx,P8=tt+yy+zz,P9=xu2θγty2θγtzP10=(y+z)G2(t)u2θγG2(t)x,P11=(α2ββ)tt+(αββ)xx(α(yz)+βyβ)yyz.(11) G,G1 and G2 are arbitrary functions.

2.2. Symmetry reductions and group invariants of (eqn5)

Here, we present the detailed calculations of group-invariant solutions of (Equation5) with the use of the Lie point symmetries given in (Equation11).

2.2.1. Invariant solutions using operator P1

We engage operator P1=/∂t, where its Lagrangian system is expressed as (12) dt1=dx0=dy0=dz0=du0.(12) Solution to the system gives function u(t,x,y,z)=U(X,Y,Z), where X=x, Y=y as well as Z=z. On inserting the function in Equation (Equation5), we achieve NLPDE (13) θUYUXX+θUZUXX+2θUXUXY+2θUXUXZ+αUXXXY+βUXXXZ=0.(13) Invoking Lie theoretic approach on (Equation13) supplies six symmetries: namely Q1=Z+U,Q2=Y+U,Q3=X+U,Q4=YY+ZZ+U,Q5=XX+(1U)U,Q6=1β[βY+α(YZ)]Y+YZ+(1+UαβU)U. We first invoke Q1 and by solving the analogous Lagrangian system, one gains U(X,Y,Z)=W(r,s)+Z, where r=X alongside s=Y. Substituting the achieved function in (Equation13), we have (14) θWrr+θWsWrr+2θWrWrs+αWrrrs=0,(14) which solves to give a topological kink solution of 3D-genBSMe (Equation5) in this instance as (15) u(t,x,y,z)=z+4αA2θtanh(A2xθ4αA2y+A1)+A3(15) with constants A1, A2 and A3 are arbitrary. We explore (Equation14) and then have G1=r+F1(s)sF1(s)W,G2=F2(s)s+(1F2(s))W,G3=rr+F3(s)s(F3(s)+s+W)W. We take F1(s)=F2(s)=F3(s)=s in the symmetries and utilize them to further reduce (Equation14). Thus, from G1, we achieve W(r,s)=f(w)s, where w=ser. On inserting the current function in Equation (Equation14) purveys the fourth-order NLODE (16) 3θwf(w)2αf(w)7αwf′′(w)+3θw2f(w)f′′(w)6αw2f′′′(w)αw3f′′′′(w)=0.(16) Moreover, operator G2 furnishes function W(r,s)=f(w)+ln(s)s, where w=r. The obtained function reduces (Equation14) to f′′(w)=0, giving solution of NLODE (Equation5) as (17) u(t,x,y,z)=z+ln(y)y+A0x+A1,(17) which is a logarithmic function solution of 3D-genBSMe (Equation5) with integration constants A0 and A1. Next, we engage G3, thus yielding W(r,s)=1/rf(w)s, where w=s/r. On applying the latest expression of W(r,s) in Equation (Equation14) secures the NLODE (18) 8θwf(w)224αf(w)36αwf′′(w)+3θw2f(w)f′′(w)12αw2f′′′(w)+2θwf(w)f′′(w)+6θf(w)f(w)αw3f′′′′(w)=0.(18) Now, we implore operator Q2 whose related characteristic equations solve to provide U(X,Y,Z)=W(r,s)+Y, where r=X and s=Z, hence transforming (Equation5) to (19) θWrr+2θWrWrs+θWsWrr+βWrrrs=0.(19) We solve the secured NLPDE and then gain a tan-hyperbolic solution of (Equation5) as (20) u(t,x,y,z)=y+4βB2θtanh(B2xθ4βB2z+B1)+B3,(20) with constants B1, B2 alongside B3, arbitrary. Further investigation of (Equation19) gives no new results. We turn attention to Q3 and then, we bestow U(X,Y,Z)=W(r,s)+X, where r=Y together with s=Z which gives a trivial solution of (Equation5). Next, in the case of Q4, we secure U(X,Y,Z)=W(r,s)+ln(Y), where r=X with s=Z/Y. We then engage the function in NLPDE (Equation13) thereby reducing it further to (21) θWrr2θsWrWrsθsWsWrr+2θWrWrs+θWsWrrαsWrrrs+βWrrrs=0.(21) Further examination of Equation (Equation21) gives the succeeding four operators, viz. G1=r,G2=W,G3=rr+[ln(s1)W]W,G4=(s1)(αsβ)s+{(αβ)ln(s1)+α(sW)+βW}W. On contemplating the linear combination of G1 and G2 secures a trivial solution of (Equation5). In the case of symmetries G3, we gain W(r,s)=1/rf(w)+ln(s1), where w=s. We then insert the function in (Equation21) and secure the first-order NLODE (22) 6αwf(w)6βf(w)+4θf(w)f(w)4θwf(w)f(w)=0.(22) The solution to the ordinary differential equation (ODE) leads to dual results (23) u(t,x,y,z)=1x{3αz3βy2θz2θy}+ln(zy1)+ln(y),u(t,x,y,z)=C0,(23) which satisfy (Equation5) where C0 is an arbitrary constant. We observe that further studies on (Equation13) yield no solution of interest.

2.2.2. Invariant solutions using operator P2

On investigating the vector field P2, it purveys a solution of (Equation5) which is of no interest.

2.2.3. Invariant solutions using operator P3

The symmetry P2=/∂y transforms (Equation5) to the NLPDE of the structure (24) θUZUXX+2θUXUXZγUTX+βUXXXZ=0(24) through relation u(t,x,y,z)=U(T,X,Z), where T=t, X=x and Z=z. We solve the gained NLPDE and consequently achieve (25) u(t,x,y,z)=4βC0θtanh(4βC02C1γt+C0x+C2z+C3)+C4,(25) which is a kink solution of 3D-genBSMe (Equation5) with constants Ci,i=1,,4, arbitrary. On the application of the Lie theoretic method on (Equation24), we secure six operators Q1=T+X+U,Q2=X+Z+U,Q3=X+TZ+12θ(2θγX)U,Q4=TT+(1+12X)X+(112U)U,Q5=(112X)X+ZZ+(1+12U)U,Q6=12T2T+(1+14TX)X+12TZZ+14θ(4θγXZθTU)U. On exploring Q1 we obtain group invariant U(T,X,Z)=W(r,s)+T, where r=XT and s=Z. The secured invariant solutions transform (Equation5) to the equation (26) γWrr+2θWrWrs+θWsWrr+βWrrrs=0,(26) which gives no solution of importance. We further explore Q2 and this gives us function U(T,X,Z)=W(r,s)+X, where r=T and s=ZX. On inserting the function in (Equation24), we have a reduced form of (Equation5) here as (27) γWrs2θWss+3θWsWssβWssss=0.(27) Solving the secured (Equation27), one gains a logarithmic-tan-hyperbolic solution of (Equation5); (28) u(t,x,y,z)=x+1θ{γA23θA32βA3ln[tanh(A2t+A3(zx)+A1)+1]8βA323θ(zx)2βA3×ln[tanh(A2t+A3(zx)+A1)1]4βA3tanh(A2t+A3(zx)+A1)γA23θA3(zx)}+23(zx)+f1(t),(28) where f1(t) is a function of t. Using Q3, no solution of interest could be obtained so we give attention to Q4 and in this case, we gain U(T,X,Z)=1/TW(r,s)+2, where we have r=(X+2)/T and s=Z. Using the gained function reduces (Equation24) to (29) 2γWr+γrWrr+2θWsWrr+4θWrWrs+2βWrrrs=0,(29) which yields four Lie-point symmetries presented here as G1=s,G2=W,G3=12rr+ss+12WW,G4=rγ2θsW. The linear combination of G1 and G2 purveys W(r,s)=f(w)+s, where w=r. On inserting the secured relation in Equation (Equation29), we achieve the second-order ODE (30) 2γf(w)+γwf′′(w)+2θf′′(w)=0.(30) The solution of (Equation5) with regard to Equation (Equation30) furnishes (31) u(t,x,y,z)=1t{γA2t+2θA1t+γA1x+2γA12θt+γx+2γ+z}+2,(31) where A1 and A2 are integration constants. Now, we explore G3 and that gives us W(r,s)=1/rf(w), where w=sr2. Thus utilizing the relation reduces (Equation5) to (32) 4θwf(w)2+2γf(w)+4γwf′′(w)+24θwf(w)f′′(w)+48βwf′′′(w)8θf(w)f′′(w)+12βf′′(w)+16βw2f′′′′(w)=0.(32) Regarding Q5, we secure U(T,X,Z)=1/(X2){W(r,s)2X}, where we have r=T and s=Z(X2)2. The obtained function eventually reduces (Equation24) to (33) γWr2γsWrs+16θsWss+6βsWss4θsWWss+2θsWs2+24βs2Wsss+12θs2WsWss+8βs3Wssss=0.(33) Now, we examine Q6, and this gives the invariant (34) U=1TW(r,s)1T(γ2θXZ+4)+2γθT2Z,r=13T23(3TX+4),s=ZT.(34) Inserting the expression of U from (Equation34) in (Equation24) furnishes the NLPDE (35) 2θWrWrs+θWsWrr+βWrrrs=0.(35) Solving the achieved NLPDE provides a solution of (Equation5) as (36) u(t,x,y,z)=1tf1(13t23(3tx+4))f2(zt)1t(γ2θxz+4)+2γθt2z,(36) where functions f1 and f2 are arbitrary and are depending on their arguments.

2.2.4. Invariant solutions using operator P4

Investigating Lie operator P4=/∂z, we gain solution to its Lagrangian system as u(t,x,y,z)=U(T,X,Y), where T=t, X=x and Y=y. Thus transforming (Equation5) to (37) θUYUXX+2θUXUXYγUTX+αUXXXY=0.(37) On the application of the Lie theoretic method on (Equation24), we secure six operators Q1=T+X+U,Q2=X+Y+U,Q3=X+TY+12θ(2θγX)U,Q4=TT+(1+12X)X+(112U)U,Q5=(112X)X+YY+(1+12U)U,Q6=12T2T+(1+14TX)X+12TYY+14θ(4θγXYθTU)U. On exploring Q1 we obtain group invariant U(T,X,Y)=W(r,s)+T, where r=XT and s=Y. The secured invariant solutions transform (Equation5) to the equation (38) γWrr+2θWrWrs+θWsWrr+βWrrrs=0,(38) which consequently solves to give a solution of (Equation5) particularly here as (39) u(t,x,y,z)=t+4αC2θtanh(C1C2(tx)γ4αC2y)+C3,(39) which is another topological kink soliton solution of 3D-genBSMe (Equation5) with arbitrary constants Ci,i=1,,3. We further explore Q2 and this fetches us relation U(T,X,Y)=W(r,s)+X, where r=T as well as s=YX. On inserting the supplied function in (Equation37), we have a transformed structure of (Equation5) in this regard as (40) γWrs2θWss+3θWsWssαWssss=0.(40) Solving the achieved (Equation40), one gains a solution of 3D-genBSMe (Equation5) here as (41) u(t,x,y,z)=x+1θ{2αA3×ln{[tanh(A2t+A3(yx)+A1)+1][tanh(A2t+A3(yx)+A1)1]}8αA323θ(yx)4αA3tanh(A2t+A3(yx)+A1)γA23θA3(yx)}+23(yx)+f1(t),(41) which is a logarithmic-tan-hyperbolic function solution with arbitrary function f1(t) where f1 depends on t.

On utilizing Q3, no solution of interest could be obtained so we give attention to Q4 and in this case, we gain U(T,X,Y)=1/TW(r,s)+2, where one has r=(X+2)/T and s=Y. Using the achieved relation reduces (Equation37) to (42) 2γWr+γrWrr+2θWsWrr+4θWrWrs+2αWrrrs=0,(42) which yields four Lie-point symmetries explicated here as G1=s,G2=W,G3=12rr+ss+12WW,G4=rγ2θsW. The linear combination of G1 and G2 purveys W(r,s)=f(w)+s, where w=r. On invoking the obtained relation in (Equation42), we achieve an ODE of order 2, that is (43) 2γf(w)+γwf′′(w)+2θf′′(w)=0.(43) Consequently, the solution of (Equation5) with regard to Equation (Equation30) purveys (44) u(t,x,y,z)=1t{γB2t+2θB1t+γB1x+2γB12θt+γx+2γ+y}+2,(44) with B1 and B2 as constants of integration. Now, we explore G3 and that gives us W(r,s)=1/rf(w), where w=sr2. Thus on engaging the relation reduces (Equation5) to (45) 4θf(w)2+2γf(w)+4γwf′′(w)+24θwf(w)f′′(w)+48αwf′′′(w)8θf(w)f′′(w)+12αf′′(w)+16αw2f′′′′(w)=0.(45) No solution(s) of interest could be achieved upon further examination of Lie point symmetry P4.

2.2.5. Invariant solutions using operators P5 and P6

The vector fields P5 and P6 do not possess invariant solutions.

2.2.6. Invariant solutions using operator P7

Symmetry reduction via P7=u/∂u2t/∂tx/∂x can be achieved if (46) u(t,x,y,z)=1tU(X,Y,Z),where we have X=xt,Y=y,alongside Z=z,(46) which is the solution to the corresponding characteristic system of P7. Therefore, using the function explicated in (Equation46) transforms 3D-genBSMe (Equation5) to NLPDE (47) 2γUX+γXUXX+2θUYUXX+2θUZUXX+4θUXUXY+4θUXUXZ+2αUXXXY+2βUXXXZ=0.(47) Lie-symmetries analysis of Equation (Equation47) yields six vector fields of the structure Q1=Z+U,Q2=Y+U,Q3=T+(1γ2θY)U,Q4=12TT+XX+ZZ+(1+12U)U,Q5=α2βTT+1β[βY+α(YZ)]Y+YZ+(1+Uα2βU)U. Group-invariant solution of Q1 yields U(X,Y,Z)=W(r,s)+Z, where we have r=X and s=Y. On using, the calculated function further reduces (Equation5) to (48) γrWrr+2γWr+2θWrr+4θWrWrs+2θWsWrr+2αWrrrs=0.(48) Thus producing four Lie operators G1=s,G2=W,G3=rγ2θsW,G4=12rr+ss+(12W12s)W. On solving G=G1+G2, we have W(r,s)=f(w)+s, where w=r. The function further reduces Equation (Equation48) to (49) 2γf(w)+γwf′′(w)+4θf′′(w)=0.(49) Eventually, the solution of (Equation5) with regard to ODE (Equation48) gives (50) u(t,x,y,z)=1t{γC2t+4θC1t+γC1x4θt+γx+y}(50) with integration constants C1 alongside C2. In addition, G3 gives a trivial solution of (Equation5) and G4 supplies the invariant solution group W(r,s)=1/rf(w)s, where w=sr2. On inserting the relation in Equation (Equation48), one gets the fourth-order NLODE (51) 4θf(w)2+2γf(w)+4γwf′′(w)+24θwf(w)f′′(w)+48αwf′′′(w)8θf(w)f′′(w)+12αf′′(w)+16αw2f′′′′(w)=0.(51) Further investigation of symmetry P7 produces no other solution(s) of importance.

2.2.7. Invariant solutions using operator P8

The Lie-point symmetry P8=t/∂t+y/∂y+z/∂z furnishes invariant (52) u(t,x,y,z)=U(X,Y,Z),where we have X=x,Y=yt,alongside Z=zt(52) that ultimately transmutes 3D-genBSMe (Equation5) to the NLPDE of the format (53) γYUXY+γZUXZ+θUYUXX+θUZUXX+2θUXUXY+2θUXUXZ+αUXXXY+βUXXXZ=0.(53) Lie symmetry analysis of Equation (Equation53) yields six vector fields of the structure Q1=12XX+YY+ZZ+(1+12U)U,Q2=X+U,Q3=Y+Z+(1γ2θX)U,Q4=α2βXX+1β[βY+α(YZ)]Y+YZ+(1+Uα2βU)U. We explore Q1 and this occasions the relation U(X,Y,Z)=1/XW(r,s)2, where one has r=X2Y together with s=X2Z. On engaging, the gained function further transforms (Equation5) to (54) 24βr2sWrrss+24βrs2Wsssr+4γrsWrs+2θsWrWs4θsWWrs4θsWWss+48αrsWrrs+48βrsWrss+4θs2WrWss+8θs2WsWrs+12θs2WsWss+24αr2sWrrrs+24αrs2Wrrss+8βs3Wssss+2γs2Wss+2θsWs2+24αs2Wrss+24βs2Wsss+γsWs+6αsWrs+6βsWss+8αr3Wrrrr+2γr2Wrr+8βr3Wrrrs+24αr2Wrrr+γrWr+6βrWrs+6αrWrr+24βr2Wrrs+2θrWr2+16θrsWrWrs+8θrsWrWss+16θrsWsWrs+8θrsWsWrr+8αs3Wrsss4θrWWrr+8θr2WrWrs+12θr2WrWrr+4θr2WsWrr+2θrWrWs4θrWWrs=0.(54) Further study reveals that no solution of importance could be achieved from Q2,,Q4.

2.2.8. Invariant solutions using operator P9

Contemplating symmetry P9=2θt/∂y2θt/∂z+γx/∂u, one has relation (55) u(t,x,y,z)=U(T,X,Y)γxy2θt,having T=t,X=x,aswellas Y=zy.(55) In utilizing the gained function in (Equation5) reduces it to an equation of the form (56) 2βTUXXXY2αTUXXXY2γTUXYγXUXX2γUX=0.(56)

Remark 2.1

We discovered that no viable results could be achieved through operators P10 and P11 with G(t)=t.

2.2.9. Invariant solutions using linear combination of P1,P2,,P4

We do the linear combination of differential generators P1, P2, P3 and P4 as P=ϵP1+P2+P3+P4, constant ϵ0, to reduce the 3D-genBSMe (Equation5) to an NLPDE in three independent variables. Hence solution to the related characteristic equations to P produces the invariants: (57) f=tϵx,g=tϵy,h=xz,Ψ=u.(57) In reference to Ψ as new dependent variables as well as taking f, g as well as h as new independent variables, 3D-genBSMe (Equation5) then transmutes into (58) αϵ4Ψfffg2θϵ3ΨfΨfgθϵ3ΨgΨff3αϵ3Ψffgh+βϵ3Ψfffh+2θϵ2ΨghΨf+2θϵ2ΨgΨfh2θϵ2ΨfΨfh+2θϵ2ΨhΨfg+3αϵ2Ψfghhθϵ2ΨhΨff3βϵ2ΨffhhθϵΨhhΨg2θϵΨhΨghαϵΨghhh+2θϵΨhhΨf+4θϵΨhΨfh+3βϵΨfhhh+γϵΨfg+γϵΨff3θΨhΨhhβΨhhhhγΨghγΨfh=0.(58) Clearly, NLPDEs (Equation58) exists in terms of three independent variables. Engaging the symmetries of (Equation58), it's altered to another NLPDE with regard to two independent variables. Equation (Equation58) produces the eight generators which are Γ1=f,Γ2=g,Γ3=h,Γ4=∂Ψ,Γ5=F1(ϵh+fg)∂Ψ,Γ6=θϵ2gg+θϵ(ϵh+f)h+γg∂Ψ,Γ7=(αβ)ϵff+ϵ(2ϵαh+2αfαgβg)g+(ϵαh+βϵh+2βf2βg)h+(αβ)ϵΨ∂Ψ,Γ8=2θϵ2(αβ)ff+2αθϵ2(ϵh+fg)g2θϵ(αfβϵh2βf+βg)h+γ(αβ)f∂Ψ, with F1 serving as an arbitrary functions of f, g and h. We combine linearly the three translational generators Γ1=/∂f, Γ2=/∂g and Γ3=/∂h as Γ=Γ1+Γ2+Γ3 to reduce Equation (Equation58). Solution to the Lagrangian system related to Γ as given before leads to the invariants (59) s=gh,r=fg,ψ=Ψ.(59) Making ψ the new dependent variable along with r as well as s as the latest independent variables, 3D-genBSMe (Equation5) becomes (60) αϵ4ψrrrsαϵ4ψrrrr+3αϵ3ψrrss3αϵ3ψrrrs+3αϵ2ψrsss3αϵ2ψrrss+αϵψssssαϵψrsssβϵ3ψrrrs3βϵ2ψrrss3βϵψrsssβψssss+γϵψrs+γψss+3θψsψss2θϵ3ψrψrsθϵ3ψsψrr+3θϵ3ψrψrr2θϵ2ψssψr4θϵ2ψsψrs+6θϵ2ψrψrs+3θϵ2ψsψrr3θϵψsψss+3θϵψssψr+6θϵψsψrs=0,(60) which is evidently an NLPDE in terms of two independent variables. One invokes the symmetries of (Equation60) to change the said equation to an ODE. Equation (Equation60) yields the symmetries M1=r,M2=s,M3=ψ,M4=θϵ3rr+θϵ3sr(θϵ3ψϵγr3ϵγs+3γr)ψ. Combining translation symmetries M1 and M2 in the structure M=νM1+M2, with non-zero real constant ν, and adopting the action earlier taken yields the invariants (61) ζ=rνsandΘ=ψ.(61) The use of group invariant solution ψ=Θ(ζ) makes it possible for Equation (Equation60) to be transformed to a new fourth-order NLODE expressed as (62) 2ϑ3(βναϵ(ν+1))Θ′′′′(ζ)+6θϑ2(ν(ϵ1)+ϵ)Θ(ζ)Θ′′(ζ)γνξ0Θ′′(ζ)=0,(62) with ξ0=2ϑ, ϑ=(ϵν), along with ζ=(νϵ)x+ϵ(ν+1)yνzνt.

Direct integration and solution of NLODE (Equation62)

Elliptic integral solution of the second kind

Integration of (Equation62) once with regard to ζ purveys (63) 2ϑ3(βναϵ(ν+1))Θ′′′(ζ)+3θϑ2(ν(ϵ1)+ϵ)Θ2(ζ)γνξ0Θ(ζ)+B0=0,(63) with B0, regarded as an integration constant. Using the assumption that Θ(ζ)=(2(βναϵ(ν+1))θ(ν(ϵ1)+ϵ))ϑΦ(ζ),μ=γνξ02ϑ3(βναϵ(ν+1)),B1=θB0(ν(ϵ1)+ϵ)4ϑ3(βναϵ(ν+1))2 thus making Equation (Equation63) becoming an ODE of second order, viz. (64) Φ′′(ζ)+3Φ(ζ)2μΦ(ζ)+B1=0,(64) which one can integrate without much stress. Multiplication of (Equation64) by Φ(ζ) and later integrating the outcome once with regard to ζ, we secure (65) Φ(ζ)2=(2Φ(ζ)3μΦ(ζ)2+2B1Φ+2B2),(65) where B2 is taken as the integration constant. Suppose that we have the cubic equation Φ(ζ)312μΦ(ζ)2+B1Φ(ζ)+B2=0 possessive of the roots β3<β2<β1, where β1, β2 and β3 are real numbers, thus we get (66) Φ(ζ)2=2(Φ(ζ)β1)(Φ(ζ)β2)(Φ(ζ)β3).(66) Equation (Equation66) furnishes the Jacobi-elliptic-cosine function solution (JCECFS), designated as [Citation11] (67) Φ(ζ)=β2+(β1β2)cn2(β1β32ζ|Q2),Q2=β1β2β1β3.(67) In this instance, we have cn(ζ|Q2) referring to the Jacobi cosine elliptic function. In addition, the solution of (Equation5) in this regard can be ultimately expressed as Θ(ζ)=2(βναϵ(ν+1))θ(ν(ϵ1)+ϵ)Φ(ζ)dζ. Furthermore, it is noteworthy and germane to state categorically assert here that special limits taken regarding the JCECFS, one could achieve diverse functions. Take for instance limQ20cn(ζ|Q2)=cos(ζ) and limQ21cn(ζ|Q2)=sech(ζ) [Citation70]. On retrograding to the usual variables, one secures a general analytic solution of 3D-genBSMe (Equation5) as (68) u(t,x,y,z)=2(βναϵ(ν+1))θ(ν(ϵ1)+ϵ){(β1β2)dn(Bζ|Q2)E(am(Bζ|Q2)|Q2)BQ2dn(Bζ|Q2)2{β2(1Q2)β1}ζQ2+(β1β2)dn(Bζ|Q2)E(am(Bζ|Q2)|Q2)BQ2dn(Bζ|Q2)2},(68) with ζ=(νϵ)x+ϵ(ν+1)yνzνt and E(ζ|Q2) depicting the second-kind-elliptic integral function relation. Additionally, am(ζ|Q2) stands for the amplitude function, whereas dn(ζ|Q2) connotes delta amplitude function with cn(ζ|Q2) denoting the Jacobi cosine function and also B=(β1β3)/2 [Citation70,Citation71]. The dynamical behaviour of solution (Equation68) is displayed with diverse values of (t,x,y) in Figures  and .

The simplest equation technique (SET)

We invoke in this section of the study, SET to gain some closed-form solutions of the third-order ODE (Equation62). This approach was established by Kudryashov [Citation39] and subsequently Vitanov made an amend to it [Citation72]. Here simplest equation to be invoked is stated as the Bernoulli as well as Riccati equations. Solution to the NLODEs can be explicated with regard to elementary functions. Let us contemplate the solution of Equation (Equation62) in the structure (69) Θ(ζ)=j=0MAj(U(ζ))j,(69) with U(ζ) satisfying the earlier-mentioned NLODEs. Real-positive integer M can be decided via balancing steps [Citation73]. In addition, A0,,AM are parameters which we have to determine.

One observes that the Bernoulli NLODE (70) U(ζ)=aU(ζ)+bU2(ζ),(70) whose solutions are explicated as (71) U(ζ)=aQ0b{Q0+cosh[a(ζ+Q1)]sinh[a(ζ+Q1)]},(71) (72) U(ζ)=a{cosh[a(ζ+K)]+sinh[a(ζ+K)]1bcosh[a(ζ+K)]bsinh[a(ζ+K)]}.(72) In the case of Riccati NLODE expressed as (73) U(ζ)=aU2(ζ)+bU(ζ)+c,(73) we shall be using the solutions U(ζ)=b2aϕ2atanh[12ϕ(ζ+K)] alongside U(ζ)=b2aϕ2atanh(12ϕζ)+sech(ϕζ2)Kcosh(ϕζ2)2aϕsinh(ϕζ2), with ϕ2=b24ac>0 and Q0, Q1, K, representing arbitrary constants.

Solutions of (Equation62) using Bernoulli equation as the simplest equation

The balancing procedure produces M = 1, thus (Equation62) assumes the structure (74) Θ(ζ)=A0+A1U.(74) Invoking the value of Θ expressed in (Equation74) into NLODE (Equation62), utilizing the Bernoulli (Equation70) and following the earlier given steps, one secures five long system of algebraic equations with regard to A0 and A1, presented as αa4νϵ4A1+αa4ϵ4A13αa4ν2ϵ3A13αa4νϵ3A1+3αa4ν3ϵ2A1+3αa4ν2ϵ2A1αa4ν4ϵA1αa4ν3ϵA1+a4βν4A1a4βνϵ3A1+3a4βν2ϵ2A13a4βν3ϵA1a2γν2A1+a2γνϵA1=0,15a3αbνϵ4A1+15a3αbϵ4A145a3αbν2ϵ3A145a3αbνϵ3A1+45a3αbν3ϵ2A1+45a3αbν2ϵ2A115a3αbν4ϵA115a3αbν3ϵA1+15a3bβν4A115a3bβνϵ3A1+45a3bβν2ϵ2A145a3bβν3ϵA1+3a3θν3A123a3θνϵ3A123a3θϵ3A12+6a3θν2ϵ2A12+9a3θνϵ2A123a3θν3ϵA129a3θν2ϵA123abγν2A1+3abγνϵA1=0, 50a2αb2νϵ4A1+50a2αb2ϵ4A1150a2αb2ν2ϵ3A1150a2αb2νϵ3A1+150a2αb2ν3ϵ2A1+150a2αb2ν2ϵ2A150a2αb2ν4ϵA150a2αb2ν3ϵA1+50a2b2βν4A150a2b2βνϵ3A1+150a2b2βν2ϵ2A1150a2b2βν3ϵA1+12a2ν3A1212a2bθνϵ3A1212a2ϵ3A12+24a2ν2ϵ2A12+36a2bθνϵ2A1212a2ν3ϵA1236a2ν2ϵA122b2γν2A1+2b2γνϵA1=0, 60b3νϵ4A1+60b3ϵ4A1180b3ν2ϵ3A1180b3νϵ3A1+180b3ν3ϵ2A1+180b3ν2ϵ2A160b3ν4ϵA160b3ν3ϵA1+60ab3βν4A160ab3βνϵ3A1+180ab3βν2ϵ2A1180ab3βν3ϵA1+15ab2θν3A1215ab2θνϵ3A1215ab2θϵ3A12+30ab2θν2ϵ2A12+45ab2θνϵ2A1215ab2θν3ϵA1245ab2θν2ϵA12=0, 24αb4νϵ4A1+24αb4ϵ4A172αb4ν2ϵ3A172αb4νϵ3A1+72αb4ν3ϵ2A1+72αb4ν2ϵ2A124αb4ν4ϵA124αb4ν3ϵA1+24βb4ν4A124βb4νϵ3A1+72βb4ν2ϵ2A172βb4ν3ϵA1+6b3θν3A126b3θνϵ3A126b3θϵ3A12+12b3θν2ϵ2A12+18b3θνϵ2A126b3θν3ϵA1218b3θν2ϵA12=0. On solving the achieved system of algebraic equations via the use of Mathematica, one gains (75) A0=A0,A1=4b(ϵν)(ανϵ+αϵβν)θ(ϵν+νϵ),a=γνανϵ3αϵ3+2αν2ϵ2+2ανϵ2αν3ϵαν2ϵ+βν3+βνϵ22βν2ϵ.(75) Thus the solution of (Equation5) is given by the hyperbolic function solution (76) u(t,x,y,z)=A0A1a{Q0b{Q0+cosh[a(ζ+Q1)]sinh[a(ζ+Q1)]}},(76) (77) u(t,x,y,z)=A0+A1a{cosh[a(ζ+K)]+sinh[a(ζ+K)]1bcosh[a(ζ+K)]bsinh[a(ζ+K)]}(77) with ζ=(νϵ)x+ϵ(ν+1)yνzνt along with K taken as an integration constant. We display the dynamics of solution (Equation77) in Figures  and  with various values of t and x.

Solutions of (Equation62) using Riccati equation as the simplest equation

We use the balancing procedure which occasions M = 1 as earlier found, so the solution of (Equation62) is of the form (78) Θ(ζ)=A0+A1U.(78) Inserting the value of Θ(ζ) as given in (Equation78) into (Equation62), making use of the Riccati equation (Equation73) as well as equating all the coefficients of the functions Uj to zero, we secure six correlating algebraic equations in respect of A0 and A1 as earlier demonstrated, which solve via the use of Mathematica to give A0=A0,A1=4b(ϵν)(ανϵ+αϵβν)θ(νϵ+ϵν),a=4αbdνϵ3+4αbdϵ38αbdν2ϵ28αbdνϵ2+4αbdν3ϵ+4αbdν2ϵ+Θ0ανϵ3+αϵ32αν2ϵ22ανϵ2+αν3ϵ+αν2ϵβν3βνϵ2+2βν2ϵ, where Θ0=4bβdν34bβϵ2+8bβdν2ϵγν and ζ=(νϵ)x+ϵ(ν+1)yνzνt. Hence the general solutions of (Equation5) can be expressed as (79) u(t,x,y,z)=A0+A1(b2aϕ2atanh[12ϕ(ζ+K)])(79) and (80) u(t,x,y,z)=A0+A1(sech(ϕζ2)Kcosh(ϕζ2)2aϕsinh(ϕζ2)b2aϕ2atanh(12ϕζ)+sech(ϕζ2)Kcosh(ϕζ2)2aϕsinh(ϕζ2)),(80) where ζ=(νϵ)x+ϵ(ν+1)yνzνt together K regarded as an integration constant. The solutions represent topological kink soliton solution and mixed dark-bright singular soliton solutions of (Equation5). We demonstrate the streaming behaviour of solutions (Equation79) and (Equation80) graphically for varying values of y with z kept constant in Figures  and .

3. Applications and discussion of the solutions and their graphical representations in physics and engineering

Solitons are regarded as self-enhancing wave packets that preserve their shapes while they are proliferating at a constant velocity. Solitons are naturally instigated by the cancellation of the influence of dispersive and nonlinear terms as they propagate. Presently, the investigation of solitons of nonlinear differential equations is quite active. The results secured here are solitonic in nature. For instance, elliptic solution (Equation68) is a smooth periodic soliton solution depicted by dark-bright soliton wave profile (as can be seen in Figures  and ). Moreover, the hyperbolic solution (Equation77) is a soliton solution which produces the bright as well as dark solitonic wave structure in Figures  alongside Figure . In addition, solutions (Equation79) and (Equation80) represent topological kink soliton and singular soliton of the underlying equation (Equation5) respectively. The first two figures depict the coexistence of dark alongside bright solitons. Bright solitons occur on a zero-intensity background, whereas dark solitons emerge as an intensity submerged in an infinitely extended constant background. Furthermore, dark and bright solitons are a very important concept in science, technology and information engineering, take for instance, in the fibre ring laser mechanism, it was observed that since there is an existence of interactions between solitons, coexistence may occur when soliton pairs are propagated together in the considered medium in addition to securing dark or bright pulses, bright–bright, dark–dark or dark–bright soliton pairs in fibre lasers. Theoretically, this has been demonstrated with the use of the nonlinear Schrödinger equation [Citation74]. The lifetime of the dark–bright soliton is revealed to be longer always than that of the dark soliton and as matter of fact becomes larger as the bright-soliton component of the dark one becomes stronger. In addition, dark–bright soliton pairs have also been observed in Kerr-type nonlinear mediums as well as optical fibre systems. Besides, in optical communication systems, dark solitons are found to be less influenced by the perturbation process, which implies that dark solitons could be preferable to bright ones. Besides, the anti-dark solitons possess profiles similar to those of the bright ones but with the exception that they exist on a nonzero background like the dark ones [Citation75].

The anti-kink wave profile depiction of hyperbolic function (Equation15) is exhibited in Figure  with the dissimilar parametric values θ=10, α=4, A1=0, A2=1, A3=5 with variables t=0, z=2, 0.2x4 as well as 3y5. In the same vein, kink solution (Equation25) is revealed in Figure  with unalike parameters θ=10, α=4, γ=4, C0=1, C1=2, C2=0, C3=1, C4=0 where variables y=0, z=1 with 3t,x3.

Figure 1. Solitary wave profile of kink solution (Equation15) at t = 0, z = 2.

Figure 1. Solitary wave profile of kink solution (Equation15(15) u(t,x,y,z)=z+4αA2θtanh⁡(A2x−θ4αA2y+A1)+A3(15) ) at t = 0, z = 2.

Figure 2. Solitary wave profile of kink solution (Equation25) at y = 0, z = 1.

Figure 2. Solitary wave profile of kink solution (Equation25(25) u(t,x,y,z)=4βC0θtanh⁡(4βC02C1γt+C0x+C2z+C3)+C4,(25) ) at y = 0, z = 1.

Figure 3. Solitary wave profile of elliptic function solution (Equation68) at t = 0.1, y = 0.

Figure 3. Solitary wave profile of elliptic function solution (Equation68(68) u(t,x,y,z)=2(βν−αϵ(ν+1))θ(ν(ϵ−1)+ϵ){(β1−β2)dn(Bζ|Q2)E(am(Bζ|Q2)|Q2)BQ2dn(Bζ|Q2)2{β2−(1−Q2)β1}ζQ2+(β1−β2)dn(Bζ|Q2)E(am(Bζ|Q2)|Q2)BQ2dn(Bζ|Q2)2},(68) ) at t = 0.1, y = 0.

Figure 4. Solitary wave profile of elliptic function solution (Equation68) at t = 25, x = 25.

Figure 4. Solitary wave profile of elliptic function solution (Equation68(68) u(t,x,y,z)=2(βν−αϵ(ν+1))θ(ν(ϵ−1)+ϵ){(β1−β2)dn(Bζ|Q2)E(am(Bζ|Q2)|Q2)BQ2dn(Bζ|Q2)2{β2−(1−Q2)β1}ζQ2+(β1−β2)dn(Bζ|Q2)E(am(Bζ|Q2)|Q2)BQ2dn(Bζ|Q2)2},(68) ) at t = 25, x = 25.

Now, we consider each of the secured solutions and their pictorial depictions. Graphical representation of elliptic solution (Equation68) is presented with 3D plot, density plot as well as 2D plot in Figure  to display the streaming behaviour of the said solution with the unalike values of the involved constants as ν=1, ϵ=2, β=1, α=1, θ=2, β1=3, β2=2, β3=1, Q = 0.005. Variables x and z exist in the interval 1x,z1 with t = 0.1 and y = 0. We display the dynamics of elliptic-solution (Equation68) in Figure  with dark–bright soliton wave profile in 3D, density as well as 2D plots with the dissimilar values of the included parameters presented as ϵ=0, ν=1, β=1, α=1, θ=1, β1=3, β2=2, β3=1, Q = 0.009. In addition, variables x and z exist in the closed interval 1.5x,z1.5 with t = 25 alongside x = 25. Now, we exhibit solitary wave solution (Equation76) in graphical forms in the usual manner in Figure  where we engage parameters including a = 1, b = 1, α=0.000000000001, β=0.00000000000001, A0=10, A1=0.6, Q0=200, Q1=20, ϵ=0.5, ν=1, where variables y = 1, z = 0 with 2t2 and 1x1. In addition, the solution is further demonstrated in Figure  where a = 1, b = 1, α=0.000000000001, β=0.00000000000001, A0=0, A1=20, Q0=200, Q1=20, ϵ=0.5, ν=1, with variables y = 1, z = 0, where we have 1t1 and 1x1.

Figure 5. Solitary wave profile of hyperbolic function solution (Equation76) at t = 10 x = 10.

Figure 5. Solitary wave profile of hyperbolic function solution (Equation76(76) u(t,x,y,z)=A0−A1a{Q0b{Q0+cosh⁡[a(ζ+Q1)]−sinh⁡[a(ζ+Q1)]}},(76) ) at t = 10 x = 10.

Figure 6. Solitary wave profile of hyperbolic function solution (Equation76) at t = 10, x = 10.

Figure 6. Solitary wave profile of hyperbolic function solution (Equation76(76) u(t,x,y,z)=A0−A1a{Q0b{Q0+cosh⁡[a(ζ+Q1)]−sinh⁡[a(ζ+Q1)]}},(76) ) at t = 10, x = 10.

Figure 7. Solitary wave profile of hyperbolic function solution (Equation77) at t = 10, x = 10.

Figure 7. Solitary wave profile of hyperbolic function solution (Equation77(77) u(t,x,y,z)=A0+A1a{cosh⁡[a(ζ+K)]+sinh⁡[a(ζ+K)]1−bcosh⁡[a(ζ+K)]−bsinh⁡[a(ζ+K)]}(77) ) at t = 10, x = 10.

Figure 8. Solitary wave profile of hyperbolic function solution (Equation77) at t = −10, x = −10.

Figure 8. Solitary wave profile of hyperbolic function solution (Equation77(77) u(t,x,y,z)=A0+A1a{cosh⁡[a(ζ+K)]+sinh⁡[a(ζ+K)]1−bcosh⁡[a(ζ+K)]−bsinh⁡[a(ζ+K)]}(77) ) at t = −10, x = −10.

Figure 9. Solitary wave profile of kink solution (Equation79) at y = 0, z = 0.

Figure 9. Solitary wave profile of kink solution (Equation79(79) u(t,x,y,z)=A0+A1(−b2a−ϕ2atanh⁡[12ϕ(ζ+K)])(79) ) at y = 0, z = 0.

Figure 10. Solitary wave profile of kink solution (Equation79) at y = 1, z = 0.

Figure 10. Solitary wave profile of kink solution (Equation79(79) u(t,x,y,z)=A0+A1(−b2a−ϕ2atanh⁡[12ϕ(ζ+K)])(79) ) at y = 1, z = 0.

Figure 11. Solitary wave profile of hyperbolic function solution (Equation80) at y = z = 0.

Figure 11. Solitary wave profile of hyperbolic function solution (Equation80(80) u(t,x,y,z)=A0+A1(sech(ϕζ2)Kcosh⁡(ϕζ2)−2aϕsinh⁡(ϕζ2)−b2a−ϕ2atanh⁡(12ϕζ)+sech(ϕζ2)Kcosh⁡(ϕζ2)−2aϕsinh⁡(ϕζ2)),(80) ) at y = z = 0.

Figure 12. Solitary wave profile of hyperbolic function solution (Equation80) at y = 2, z = 0.

Figure 12. Solitary wave profile of hyperbolic function solution (Equation80(80) u(t,x,y,z)=A0+A1(sech(ϕζ2)Kcosh⁡(ϕζ2)−2aϕsinh⁡(ϕζ2)−b2a−ϕ2atanh⁡(12ϕζ)+sech(ϕζ2)Kcosh⁡(ϕζ2)−2aϕsinh⁡(ϕζ2)),(80) ) at y = 2, z = 0.

Next, we contemplate the hyperbolic function solution (Equation77). The streaming pattern of soliton solution (Equation77) is displayed with dark soliton wave profile in 3D plot, density plot and 2D plots and presented in Figure  with diverse values of the engaged parameters including β=1, ϵ=0, ν=1, α=0.000000000001, θ=1, γ=4, b = 1, K = 0, A0=0. Also, variables y and z occur in the closed interval 1.1y,z1.1 with t = 10 alongside x = 10. Furthermore, Figure  depicts the bright soliton wave profile of (Equation77) exhibited in 3D plot, density plot as well as 2D plot. Various values of the involved parameters are given as ν=10, α=10, β=10, ϵ=0, θ=1, γ=4, b = 1, K = 0, A0=0. Besides, variables y and z eventuate in the closed interval 1y,z1 with t = −10 and x = −10. We can easily add here that Figures  and  represent a one single-peak soliton wave of (Equation5). It is worthy of note to include here that the association of Figures  and  to the hyperbolic solution (Equation77) is in consonance with already established fact because it is well known that hyperbolic secant characterizes bright soliton profile. This bright soliton solution usually takes a structure of bell-shaped figure which propagates undistorted without any alteration or altercation in shape for arbitrarily long distances. Nonetheless, dark soliton solutions which are invariably configured also as topological optical solitons, are represented by hyperbolic tangent. We represent the dynamics of topological kink soliton solution (Equation79) in Figure . Actually, a kink ascends from one asymptotic state to another. The kink wave is a paramount aspect of numerous physical phenomena that consist of impulsive systems, self-reinforcing, as well as reaction–diffusion–advection. It is very important to explore kink wave in relation to solutions of partial differential equations. The 3D plot, density plot and 2D plot of (Equation79) are given in Figure  with unalike values of the various included parameters stated as α=0.000000000001, β=1, ν=2.5, ϵ=0, θ=0.06667, γ=6.25, b = 2, ϕ=2, K = −0.9, d = 1, A0=100. Also, variables t as well as x eventuate in the closed interval 0t1 and 0x2 with y = 0 and z = 0. Moreover, we give the 3D, density and 2D plots of soliton (Equation79) in Figure  with dissimilar values of the engaged parameters as α=0.000000000001, ν=0.8, β=1, ϵ=0, θ=0.02, γ=6.25, b = 2, ϕ=2, K = −0.9, d = 1, A0=100. Besides, variables t as well as x existing in the closed interval 0t1 and 0x2 with y = 1 and z = 0.

The streaming behaviour of singular soliton solution (Equation80) is presented in Figures  and . Singular solitons can be associated with a solitary wave whose centre is an imaginary position. In addition, their intensity turn out to be stronger and as a result they are unstable. The 3D plot, density plot as well as 2D plot of singular soliton (Equation80) is projected in Figure . The parameters invoked take up the values as ν=2, α=0.000000000001, β=1, ϵ=0, θ=0.06667, γ=6.25, b = 2, ϕ=2, K = −0.9, d = 1, A0=100. Also, variables t as well as x eventuate in closed interval 0t1 and 0x2 with y = 0 and z = 0. We observe that the points of singularities for the solution in association with those values exist in the spatial domain 1x2. Lastly, the dynamics of soliton (Equation80) is further exhibited in Figure  via 3D plot, density plot and 2D plot representations. Varying values of the involved parameters are stated as α=0.000000000001, ν=0.8, β=1, ϵ=0, θ=0.02, γ=6.25, b = 2, ϕ=2, K = 0.009, d = 1, A0=100. More so, variables t as well as x occur in the closed-interval 0t1 and 0x2 with y = 2 and z = 0. The singularity in this case exists at the spatial point x = 1.5. We note that Figures  and  produce multi-peak soliton waves.

Next, we endeavour to examine the connectivity ensuing between our graphic depictions and real-world problems. To have a good understanding of complex situations and then obtain real-world practical applications, mathematical visualization is needed. We particularly note that kink-shaped structures (as can be seen in Figures  and ) are prominent in the research work, which in the real world perfectly depicts the shape of waterfalls (see the images in Figures  and ).

Figure 13. Connection of the various kink-shaped structures to the real-world application through waterfalls. https://www.newyorkupstate.com/outdoors/2020/10/17-must-see-waterfalls-that-should-be-on-your-upstate-ny-bucket-list.html.

Figure 13. Connection of the various kink-shaped structures to the real-world application through waterfalls. https://www.newyorkupstate.com/outdoors/2020/10/17-must-see-waterfalls-that-should-be-on-your-upstate-ny-bucket-list.html.

Figure 14. Relating the various kink-shaped structures to the real-world application through waterfalls. https://www.americanrivers.org/2022/08/what-makes-a-waterfall-a-waterfall/.

Figure 14. Relating the various kink-shaped structures to the real-world application through waterfalls. https://www.americanrivers.org/2022/08/what-makes-a-waterfall-a-waterfall/.

By visualizing the structure of kink-wave viz-a-viz its symbolic implication in waterfalls, it could be of help to ocean scientists and engineers in studying the dynamics of fluids. Besides, kink solutions have a range of uses including resolving issues and bugs, in code as well as tackling bottlenecks or unexpected behaviours, in technology and software systems. In the realm of business management, they assist managers in overcoming challenges and finding solutions to market demands and competition. Additionally, they aid healthcare professionals in handling complications during treatments. The applications of kink solutions are extensive spanning across aspects of life. They involve adaptability, problem-solving skills and the ability to overcome obstacles thus contributing to progress and advancement in fields.

3.1. Significance and application of exact solutions in science and engineering fields

This work presents various dynamics of exact solutions to the underlying problem (Equation5) which range from hyperbolic, logarithmic, algebraic (with and without arbitrary functions) to elliptic function solutions. Therefore, it is expedient to present the significant of exact solutions in science and engineering fields. In general relativity, an exact solution is commonly referred to as a solution of the Einstein field equations in which its derivation does not include the engagement of simplifying assumptions. However, the derivation starting point may be an idealized situation, just for instance, the case of a perfectly spherical shape of matter. In mathematics, securing an exact solution amounts to achieving a Lorentzian manifold that has been equipped with tensor fields modelling states of ordinary matter. These could appear as a fluid or non-gravitational fields (classical) such as the electromagnetic field [Citation76].

Exact (closed-form) solutions associated to mathematical models play an exerting crucial role in having a proper perspective (understanding) of qualitative features related to many processes and phenomena arising in various areas of natural science. Besides, exact solutions of nonlinear DEs graphically exhibit and allow unravelling the mechanisms which are included in various complex nonlinear phenomena such as multiplicity or absence of steady states under diverse conditions, spatial localization of transfer processes, existence of peaking regimes, to mention but a few. Moreover, simple solutions are often involved in teaching many courses. This enables the use of a good number of specific examples depicting basic tenets of a theory that admit mathematical formulation (such as can be found in hydrodynamics, heat and mass transfer theory, gas dynamics, nonlinear optics, wave theory and various other fields of research).

Furthermore, even those seemingly special exact solutions with no clear physical meaning can be utilized as test problems for the verification of the consistency as well as estimation of errors of various asymptotic, numerical, as well as approximate analytical techniques. Significantly, exact solutions can also be employed as a basis for the perfection and testing of computer algebra software packages in attaining solution to DEs. These packages include Mathematica, MATLAB, Maple, CONVODE and diverse others.

It is pertinent to say that many models found in biology, physics and chemistry comprise of empirical functions or empirical parameters. In addition, exact solutions give researchers the opportunity of designing and also running experiments, through the creation of appropriate natural (boundary and initial) conditions, in determining the aforementioned functions or parameters [Citation77].

Remark 3.1

We note that an exact solution is typically constructed through the use of mathematical equations or proofs. Besides, it is commonly represented through a symbolic representation or closed-form expression. A solution is exact in the sense that for any value of the variables in a given problem, it is valid, and it can also be evaluated with any precision. Therefore, an exact solution refers to a symbolic representation of a value that precisely solves a given equation. However, an equation is said to be a closed form if it solves a given problem regarding mathematical operations and functions from a given generally accepted set. Take, for instance, an infinite sum that would generally not be considered closed-form. Thus a solution to a given problem that can be presented in “closed form” with regard to known functions, constants and so on is usually called an analytic solution.

4. Conservation laws of 3D-genBSMe (eqn5)

This section gives the result gained when the conserved quantities of 3D-genBSMe (Equation5) were derived via the utilization of the long-established Noether's theorem [Citation78] as highlighted in [Citation21].

4.1. Establishment of conserved quantities via Noether's theorem

On utilizing the long-established Noether's theorem [Citation78] to calculate the conserved vectors of the 3D-genBSMe (Equation5), the Noether's theorem is stated in the first place, to have some background ideas about the technique.

Theorem 4.1

If Q is regarded as a Noether symmetry operator corresponding to Lagrangian L in such a way that L=L(x,Ψ,Ψ(1),,Ψ(k1)) of mth-order system of k PDEs expressed as (81) Ωα=(x,Ψ,Ψ(1),,Ψ(m))=0,with α=1,,k,(81) with x as well as Ψ representing independent together with dependent variables, respectively, then there exists a vector called C=(C1,C2,,Cm) relating to L such that (82) Ci=NiLBi,i=1,,m,(82) with gauge function Bi dependent on x, is accented to as conserved vector for (Equation5) related to operator Q [Citation78].

The Noether operators are given by (83) Ni=ξi+WαδδΨiα+s1Di1Dis(Wα)δδΨii1i2isα,i=1,,m,(83) and Euler–Lagrange  operators are defined as [Citation21] (84) δδΨα=Ψα+s1(1)sDi1DisΨi1i2isα,α=1,,k.(84)

Lemma 4.1

The 3D-genBSMe (Equation5) forms the Euler–Lagrange relation with functional (85) J(u)=0000L(t,x,y,z,ut,ux,uy,uz,uxx,uxy,uxz)dtdxdydz,(85) where Lagrange-conforming function of L is expressed as (86) L=12γutux+12αuxxuxy12θux2uy+12βuxxuxz12θux2uz.(86)

Proof.

We comment that second-order Lagrangian of the understudy model is explicated via (Equation86), due to the fact that Euler–Lagrange relation δL/δu=0 is satisfied as anticipated.

Moreover, we note that in Section 2, the 3D-genBSMe (Equation5) has 11 Lie point symmetries which are expressed in (Equation11). By utilizing the result given in [Citation21], we conclude that vector fields P1,P2,P3,P4,P5,P6,P7,P8,P9,P10 and P11 (where the arbitrary functions G1(t), G(t,zy) and G2(t) satisfy the derivatives G1(t)=0, Gt(t,zy)=0 and G2′′(t)=0 respectively) are variational symmetries. Therefore, the conserved vectors (Ct,Cx,Cy,Cz) related to 11 Noether symmetries P1,P2,P3,P4,P5, P6,P7,P8,P9,P10 and P11 with the aid of [Citation79] Ck=Lτk+(ξαψxjατj)(Lψxkαl=1kDxl(Lψxlxkα))+l=kn(ηlαψxlxjατj)Lψxkxlα are, respectively, given by C1t=12αuxxuxy12θux2uy+12βuxxuxz12θux2uz,C1x=34αutuxxy12γut214αuxxuty12αutxuxy+θutuxuy+34βutuxxz14βuxxutz12βutxuxz+θutuxuz,C1y=14αutuxxx14αuxxutx+12θutux2,C1z=14βutuxxx14βuxxutx+12θutux2;C2t=12γux2,C2x=34αuxuxxy14αuxxuxy+12θux2uy+34βuxuxxz14βuxxuxz+12θux2uz,C2y=14αuxxxux14αuxx2+12θux3,C2z=14βuxxxux14βuxx2+12θux3;C3t=12γuxuy, C3x=34αuyuxxy12γutuy12αuxy214αuxxuyy+θuxuy2+34βuyuxxz12βuxyuxz14βuxxuyz+θuxuyuz,C3y=12γutux+14αuxxuxy+14αuxxxuy+12βuxxuxz12θux2uz,C3z=14βuxxxuy14βuxxuxy+12θux2uy;C4t=12γuxuz,C4x=34αuzuxxy12γutuz12αuxyuxz14αuxxuyz+θuxuyuz+34βuzuxxz12βuxz214βuxxuzz+θuxuz2,C4y=14αuxxuxz+14αuxxxuz+12θux2uz, C4z=12γutux+12αuxxuxy12θux2uy+14βuxxuxz+14βuxxxuz;C5t=12γG1(t)ux,C5x=12γG1(t)ut34αG1(t)uxxyθG1(t)uxuy34βG1(t)uxxzθG1(t)uxuz12γG1(t)u,C5y=14αG1(t)uxxx12θG1(t)ux2,C5z=14βG1(t)uxxx12θG1(t)ux2;C6t=12γuxG(t,zy),C6x=34αuxxyG(t,zy)34βuxxzG(t,zy)θuxuzG(t,zy)θuxuyG(t,zy)+12γutG(t,zy)14αGy(t,zy)uxx+14βGz(t,zy)uxx12γGt(t,zy)u, C6y=14αuxxxG(t,zy)12θux2G(t,zy),C6z=14βuxxxG(t,zy)12θux2G(t,zy);C7t=αtuxxuxyθtux2uy+βtuxxuxzθtux2uz12γuux12γxux2,C7x=34αuuxxy+34βuuxxz12γuut+θuuxuz+θuuxuyγtut2+32αtutuxxy12αtuxxutyαtutxuxy+2θtutuxuy+32βtutuxxz12βtuxxutzβtutxuxz+2θtutuxuzαuxuxy+34αxuxuxxy14αuxxuy14αxuxxuxy+12θxux2uyβuxuxz+34βxuxuxxz14βuxxuz14βxuxxuxz+12θxux2uz, C7y=14αuuxxx+12θuux2+12αtutuxxx12αtuxxutx+θtutux212αuxxux+14αxuxxxux14αxuxx2+12θxux3,C7z=14βuuxxx+12θuux2+12βtutuxxx12βtuxxutx+θtutux212βuxxux+14βxuxxxux14βxuxx2+12θxux3;C8t=12αtuxxuxy12θtux2uy+12βtuxxuxz12θtux2u,z12γyuxuy12γzuxuz, C8x=34αtutuxxy12γtut214αtuxxuty12αtutxuxy+θtutuxuy+34βtutuxxz14βtuxxutz12βtutxuxz+θtutuxuz12γyutuy12γzutuz12αyuxy214αuxxuy14αyuxxuyy+34αyuyuxxy+θyuxuy2+34αzuzuxxy12αzuxyuxz14αzuxxuyz12βyuxyuxz14βyuxxuyz+34βyuyuxxz+θyuxuyuz+θzuxuyuz14βuxxuz+34βzuzuxxz12βzuxz214βzuxxuzz+θzuxuz2,C8y=14αtutuxxx14αtuxxutx+12θtutux2+12γyutux+14αyuxxuxy+14αyuxxxuy+12βyuxxuxz12θyux2uz14αzuxxuxz+12θzux2uz+14αzuxxxuz, C8z=14βtutuxxx14βtuxxutx+12θtutux2+12γzutux14βyuxxuxy+14βyuxxxuy+12θyux2uy+12αzuxxuxy12θzux2uy+14βzuxxuxz+14βzuxxxuz;C9t=12γu12uxuzuxuyux,C9x=2θ2γtuz2ux+2θ2γtuy2ux+4θ2γtuzuyuxβθγtuxz2αθγtuxy2+xuzuxθ+xuyuxθαθγtuxzuxyβθγtuxzuxyβθ2γtuzzuxxαθ2γtuyzuxxβθ2γtuyzuxxαθ2γtuyyuxx+3βθ2γtuzuxxz+3βθ2γtuyuxxz+3αθ2γtuzuxxy+3αθ2γtuyuxxytuzutθtuyutθ12βuxz12αuxy+34xβuxxz+34uxxy12ut,C9y=12ux2+utux14αuxxαθ2γtuxzuxx+βθγtuxzuxx+αθ2γtuxyuxx+14uxxx+αθ2γtuzuxxx+αθ2γtuyuxxx, C9z=12ux2+utux14βuxx+βθ2γtuxzuxx+αθγtuxyuxxβθ2γtuxyuxx+14xβuxxx+βθ2γtuzuxxx+βθ2γtuyuxxx;C10t=θG2(t)ux212γyG2(t)ux12γzG2(t)ux,C10x=3αθ2γG2(t)uxuxxyαθ2γG2(t)uxxuxy+θ2γG2(t)ux2uy+3βθ2γG2(t)uxuxxzβθ2γG2(t)uxxuxz+θ2γG2(t)ux2uz12γyG2(t)ut12γzG2(t)ut+34αzG2(t)uxxy+34βyG2(t)uxxz+θyG2(t)uxuz+θzG2(t)uxuy+34αyG2(t)uxxy+θyG2(t)uxuy+34βzG2(t)uxxz+θzG2(t)uxuz14αG2(t)uxx14βG2(t)uxx+12γyG2′′(t)u+12γzG2′′(t)u,C10y=αθ2γG2(t)uxxxuxαθ2γG2(t)uxx2+θ2γG2(t)ux3+14αyG2(t)uxxx+12θyG2(t)ux2+14αzG2(t)uxxx+12θzG2(t)ux2, C10z=βθ2γG2(t)uxxxuxβθ2γG2(t)uxx2+θ2γG2(t)ux3+14βyG2(t)uxxx+12θyG2(t)ux2+14βzG2(t)uxxx+12θzG2(t)ux2;C11t=α22βtuxxuxyαθ2βtux2uyαtuxxuxy+θtux2uyαθ2βtux2uz+12αtuxxuxzβtuxxuxz+θtux2uzαγxux22β+12γxux2+αγyuxuy2β+12γyuxuyαγzuxuy2β+12γyuxuz, C11x=α22βyuxy2α22βzuxy2α22βuxuxy+α24βuyuxx+α24βyuyyuxxα24βzuyyuxxα24βxuxyuxx3α24βyuyuxxy+3α24βzuyuxxy+3α24βxuxuxxy+3α24βtuxxyutα24βtuxxutyα22βtuxyutx+θα2βxuzux2+θα2βxuyux2+12yuxy2αγα2βtut2θαβyuy2ux+θαβzuy2uxθαβyuzuyux+θαβzuzuyux12αuxuxz+12αuxuxy+αyuxzuxy12αzuxzuxy+14αuzuxx+12αyuyzuxx14αzuyzuxx+14αyuyyuxx14αxuxzuxx+14αxuxyuxx34αyuyuxxz+34αzuyuxxz+34αxuxuxxz34αyuzuxxy34αyuyuxxy34αxuxuxxy+γα2βyuyutγα2βzuyut+θαβtuzuxut +θαβtuyuxut+34αtuxxzut32αtuxxyut14αtuxxutz+12αtuxxuty12αtuxzutx+αtuxyutx12θxuzux212θxuyux2+12βyuxz2+γtut2θyuz2uxθyuy2ux2θyuzuyux+12βuxuxz+12βyuxzuxy+14βyuzzuxx+14βyuyzuxx+14βxuxzuxx34βyuzuxxz34βyuyuxxz34βxuxuxxz+12γyuzut+12γyuyut2θtuzuxut2θtuyuxut32βtuxxzut+12βtuxxutz+βtuxzutx,C11y=12θxux3+αθ2βxux3+αθ2βyuzux2αθ2βzuzux2θtutux2+αθ2βtutux2+14αuxxuxα24βuxxux14αxuxxxux+α24βxuxxxux12γyutux αγ2βyutux+αγ2βzutux+14αxuxx2α24βxuxx214αyuxzuxx+12αzuxzuxx12βyuxzuxx14αyuxyuxxα24βyuxyuxx+α24βzuxyuxx14αyuzuxxx14αyuyuxxxα24βyuyuxxx+α24βzuyuxxx12αtuxxxut+α24βtuxxxut+12αtuxxutxα24βtuxxutx,C11z=αθ2βtutux2+14αtutuxxx14αtuxxutx12βtutuxxx+12βtuxxutxθtutux212γyutux+αθ2βxux314αuxxux+14αxuxxxux14αxuxx2+14βuxxux14βxuxxxux+14βxuxx212θxux3αθ2βyux2uy14αyuxxuxy14αyuxxxuy+14βyuxxuxy14βyuxxxuy+αθ2βzux2uy14αzuxxuxy+14αzuxxxuy14βyuxxuxz14βyuxxxuz.

4.1.1. Application of the conserved quantities related to Noether's symmetries in physics and engineering

Conservation laws are revealed to be fundamental laws of nature. Generally speaking, the cumulative quantity of property controlled by that law remains unaltered in the course of physical processes. Regarding classical physics, conservation laws consist of the conservation of energy, linear momentum, mass (or matter), electric charge and angular momentum. Having said that, the integration of a given non-trivial conservation law over the spatial domain given as ΩR purveys a conserved integral of the form [Citation21] (87) T[u]=ΩCdx|E,(87) where we have E stands for the space of solutions of (Equation5), which is presented by the equation as well as its differential consequences embedded in the jet space.

We now present the corresponding conserved quantities, which are known to have a variety of meanings and uses in the physical sciences, in relation to some of the conservation laws that have been achieved. Relative to vector (C1t,C1x,C1y,C1z) furnishes (88) T1[u]=Ω(12αuxxuxy12θux2uy+12βuxxuxz12θux2uz)dx,(88) which represents the conserved quantity of energy. Meanwhile, with regard to (Cit,Cix,Ciy,Ciz,i=2,3,4), we have the conserved relations (89) T2[u]=Ω12γux2dx,T3[u]=Ω12γuxuydx,andT4[u]=Ω12γuxuzdx(89) preserving conservation of momenta. Related to (Cit,Cix,Ciy,Ciz,i=5,6), one has (90) T5[u]=Ω12γG1(t)uxdx,andT6[u]=Ω12γG1(t,zy)uxdx(90) representing the generalized momenta of model (Equation5). Next, we examine conserved vectors (C7t,C7x,C7y,C7z) and (C8t,C8x,C8y,C8z), corresponding to these, we have (91) T7[u]=Ω(12αtuxxuxyθtux2uy+βtuxxuxzθtux2uz12γuux12γxux2)dx,T8[u]=Ω(12αtuxxuxy12θtux2uy+12βtuxxuxz12θtux2uz12γyuxuy12γzuxuz)dx,(91) which represent conservations of energy. Similarly, the other conservation laws represent mathematically conserved quantities if one adheres to the previously described pattern. In mechanical engineering, the conservation of energy is applied to design efficient machines and systems. For instance, in the design of engines and turbines, understanding how energy is conserved and transferred allows engineers to optimize performance. Besides, for scientific applications in physics, the conservation of energy is fundamental. It is applied in fields such as thermodynamics, which governs heat transfer and works in various processes. In particle physics, the conservation of momentum is essential for understanding the behaviour of subatomic particles in collisions. In aerospace engineering, the conservation of momentum is crucial in understanding the motion of rockets and spacecraft. Engineers use this principle to design control systems for accurate manoeuvring [Citation80].

5. Concluding remarks

In this research paper, we examined a generalized nonlinear multi-dimensional breaking soliton equation (Equation5) where various classical solutions for the model are secured via the theory of the Lie group. For the very first time, the generalized equation was comprehensively studied via Lie group approach which occasions a detailed reduction of the said equation using its Lie point symmetries. The implementation of the technique assisted us in gaining an ordinary differential equation which is integrable to secure a solution to the underlying equation. Furthermore, the simplest equation technique with regard to Bernoulli and Riccati equations was utilized. As a result, we constructed soliton solutions consisting of elliptic integral function, topological kink wave, algebraic, logarithmic, dark-bright and singular solutions. The featuring of the elliptic function solution gave the most general solution of the equation which disintegrates under some certain limits to produce hyperbolic and various other elementary trigonometric function solutions. In addition, we discussed the solutions as well as the graphical demonstration of the secured results which were presented to view their streaming patterns. These graphical representations showcase appreciable wave profiles of the solutions. They include dark–bright, bright, dark, singular and kink waves. Lastly, we constructed the conserved quantities of (Equation5) by utilizing the Noether theorem which occasions 10 local conserved vectors of the equation under study. Furthermore, we outlined various significance and applications of the obtained conservation laws as well as exact solutions which included exploration of the shape and we also visualize it to see how it related to the real-world problem. These, as a result, made the work in this paper novel and original. The results secured in this paper may be of particular interest to scientists working in various fields of science and engineering, especially in physics, marine science and ocean engineering, for their analysis because of their applicability. The future scope of this work includes the opportunity of engaging the obtained conservation laws to find more solutions to the model using double reduction technique.

Authors' contributions

All authors wrote the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors did not receive funding from any organization for this work.

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