Experimental Study on Glazing Impacts on Rectification Performance of Planar Thermal Diode Integrated Collector Storage Systems

Abstract

Thermal diodes are innovative tools to rectify the heat transfer mechanism in integrated collector storage (ICS) solar water heating (ICSSWH) systems and reduce ambient heat losses. This study analyzes an innovative planar thermal diode ICSSWH and aims to determine how the glazing affects the efficiency and dynamics of planar diodes. Furthermore, the robust ability of planar diodes to rectify the heat transfer mechanism is proven. Hence, an experimental setup was fabricated and analyzed outdoors during the day to observe the planar diode’s dynamics comprehensively. The obtained results illustrate the strong effects of glazing on the dynamics and diodicity of the planar diode. The stored water obtains the highest temperature of 64 °C in the glazed scenario and 50 °C in the unglazed one. Hence the glazing improves collection and retention efficiencies in which the collection efficiency reaches 52.81% and 35.56%, while the retention efficiency has peak values of 11.04% and 3.22% in the glazed and unglazed scenarios. The partial vacuum is another crucial factor that slightly affects the stored water temperature and efficiencies compared to the glazing strategy. Hence the glazing significantly reduces ambient heat losses in the planar diode as a robust thermal rectifier.

Disclosure statement

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

Additional information

Notes on contributors

Hadi Farzan

Hadi Farzan received the M.Sc. and Ph.D. degrees from the Shiraz University and Shahid Bahonar University of Kerman in 2012 and 2017, respectively. He has over 10 years of experience in research and teaching. He is currently Associate Professor of Mechanical Engineering at the Higher Educational Complex of Bam. He has published 50 research papers in international journals and conferences. His research interests are in the field of heat transfer, energy, and energy systems.

Farzin Hasanzadeh Dehnavi

Farzin Hasanzadeh Dehnavi is a M.Sc. student in Department of Mechanical Engineering, Faculty of Engineering at Higher Educational Complex of Bam. He obtained his bachelor’s degree in Energy and Manufacturing Engineering in 2013 from Kar Higher Education Institute. He is now working as a professional energy engineer in Bam University of Medical Sciences.

Mehran Ameri

Mehran Ameri is Professor of the Mechanical Engineering at Shahid Bahonar University of Kerman, Iran. He received his M.Sc. and Ph.D. degrees from Isfahan University of Technology in 1995 and 2003, respectively. He has over 30 years of experience in research and teaching. He is the author or coauthor of more than 200 peer-reviewed or conference publications and reviewer for various journals. His research interests include solar energy, renewable energy, heat transfer, and thermodynamics.