Sajjad Tariq A. Shafi, Mohammed K. Al-Saadi, Ameer Abed Jaddoa^*

Frontiers in Heat and Mass Transfer, Vol.23, No.2, pp. 703-719, 2025, DOI:10.32604/fhmt.2025.063118 - 25 April 2025

Abstract To improve the heat transfer rate and thermal performance of the solar air heater due to low efficiency, new techniques, such as artificial roughness, barriers, and obstacles, should be used to increase the heat exchange between the fluid and the absorber. In this research, perforated V-shaped blockages with new geometric shapes, which are circular, hexagonal, square, rectangular, and triangular, were used. They were fixed on the absorber plate inside the channel with dimensions of 1.5 m × 0.5 m × 0.05 m, which increased the exit temperature of the air passing through the channel. The… More > Graphic Abstract

Shuilian Li¹, Fan Zeng¹, Xinli Wei^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.5, pp. 939-955, 2024, DOI:10.32604/fdmp.2023.043614 - 07 June 2024

Abstract In order to increase the efficiency of solar air collectors, a new variant with a protrusion is proposed in this study, and its performances are analyzed from two points of view, namely, in terms of optics and thermodynamics aspects. By comparing and analyzing the light paths of the protrusion and the dimple, it can be concluded that when sunlight shines on the dimple, it is reflected and absorbed multiple times, whereas for the sunlight shining on the protrusion, there is no secondary reflection or absorption of light. When the lighting area and the properties of… More >

Ghobad Shafiei Sabet^1,*, Ali Sari¹, Ahmad Fakhari^2,*, Nasrin Afsarimanesh³, Dominic Organ⁴, Seyed Mehran Hoseini¹

Frontiers in Heat and Mass Transfer, Vol.22, No.2, pp. 491-509, 2024, DOI:10.32604/fhmt.2024.048290 - 20 May 2024

Abstract This study conducts both numerical and empirical assessments of thermal transfer and fluid flow characteristics in a Solar Air Collector (SAC) using a Delta Wing Vortex Generator (DWVG), and the effects of different height ratios (R = 0.6, 0.8, 1, 1.2 and 1.4) in delta wing vortex generators, which were not considered in the earlier studies, are investigated. Energy and exergy analyses are performed to gain maximum efficiency. The Reynolds number based on the outlet velocity and hydraulic diameter falls between 4400 and 22000, corresponding to the volume flow rate of 5.21–26.07 m/h. It is More >