Vol.:(0123456789) 1 3 Journal of Thermal Analysis and Calorimetry https://doi.org/10.1007/s10973-020-10248-2 Thermal performance modeling of modifed absorber wall of solar chimney‑shaped channels system for building ventilation Maher Dhahri 1  · Saeed Nekoonam 2  · Aouinet Hana 3  · Mamdouh El Haj Assad 4  · Müslüm Arıcı 5  · Mohsen Sharifpur 6,7  · Habib Sammouda 1 Received: 14 July 2020 / Accepted: 14 September 2020 © Akadémiai Kiadó, Budapest, Hungary 2020 Abstract This paper aims to compare the thermal performance of four diferent confgurations of absorber wall for the solar chimney- shaped channels. A detailed energy and exergy analysis has been performed for various solar radiation intensities. Using Computational Fluid Dynamics technique, the four confgurations are examined in order to determine the optimal confgura- tion. The confgurations are described by a fat corner, rounded corner, triangle corner and trapeze corner. The Computational Fluid Dynamics results were validated against experimental data from the literature, and a good agreement between the prediction and measurement was achieved. The results indicate that (1) the exergy and energy efciencies increase with solar radiation and the energy efciency is always higher than the exergy efciency, (2) the energy efciency of triangle corner is 50% higher than that of the trapeze corner confguration, 67% higher than that of the rounded corner and 2% higher than that of the fat corner when the solar radiation intensity is 480 W m −2 , (3) the triangle corner increases the air temperature and pressure in the solar chimney which results in an optimum air mass fow rate which enhances the ventilation and (4) the comparison among the four confgurations shows that the triangle corner confguration results in higher efciency when a solar chimney is used as a natural ventilator. Keywords Solar chimney · CFD · Thermal performance · Building List of symbols t Time (s) k Turbulent kinetic energy (m 2  s −2 ) l Turbulent mixing length (m) i, j Cartesian coordinate index C a Constant pressure specifc heat (J kg −1  K −1 ) T Temperature (K) K Thermal conductivity (W m −1  K −1 ) * Mamdouh El Haj Assad massad@sharjah.ac.ae * Mohsen Sharifpur mohsen.sharifpur@up.ac.za; mohsensharifpur@duytan.edu.vn Maher Dhahri maher.dhahri@enit.utm.tn Saeed Nekoonam saeednekoonam@gmail.com Aouinet Hana aounethana@gmail.com Müslüm Arıcı muslumarici@gmail.com Habib Sammouda habib.sammouda@fsm.rnu.tn 1 Laboratory of Energy and Materials (LabEM) (LR11ES34), High School of Sciences and Technology of Hammam Sousse, Sousse University, BP 4011, Hammam Sousse, Tunisia 2 Department of Renewable Energies and Environment, Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran 3 Private Higher School of Engineering and Applied Technologies, Sousse, Tunisia 4 SREE Department, University of Sharjah, Sharjah, United Arab Emirates 5 Mechanical Engineering Department, Engineering Faculty, Kocaeli University, Umuttepe Campus, 41001 Kocaeli, Turkey 6 Institute of Research and Development, Duy Tan University, Da Nang 550000, Viet Nam 7 Department of Mechanical and Aeronautical Engineering, University of Pretoria, Pretoria 0002, South Africa