Abstract
This study addresses oxygen re-absorption characteristics of an oxygen depleted, quiescent body of Jet A-1 fuel when sparged with air. A small scale test set-up has been specifically designed and used to investigate the effects of air flowrate, exposed sparger surface area and sparger porosity upon the time period for fuel to reach a near fully saturated condition (the regeneration time). Analysis of the results show sparger surface area to be the most significant variable in affecting the normalised rate of change of regeneration time, although the effects of air flowrate and sparger porosity are also highly significant. Non-linear regression analysis has provided mathematical expressions relating %O2 saturation to time for each combination of the independent variables tested. Scaling laws are also proposed (using dimensional analysis) such that the laboratory results may be projected to a dimensionally similar prototype. Through the dimensional analysis, equations are derived allowing sensitivity of the regeneration time, to changes in both the independent variables and temperature dependent parameters, to be explored.
Acknowledgements
This work formed part of an MEng degree in Mechanical Engineering, at the University of the West of England to JH, funded by Airbus Operations Limited. J. Henshaw wishes to thank Adam Harris of Rolls Royce and Anthony May of the University of the West of England.
Notes
i Sparging is the process of introducing fine gas bubbles to a liquid to promote a state of equilibrium of dissolved gas content within it. A sparger is the device through which the gas is passed and distributed within the liquid.
ii Porosity in this paper defines the size of the pores (within the sparger) through which the air passes into the fuel.
‡ Gas hold-up is defined as the percentage by volume of gas in the two phase fluid.
iii A has a determinant of −2.