Experimental Investigation for the Performance of the Solar Air Dryer with Vortex Generator

Abstract

Experimental simulations were conducted to analyze the thermal properties of a solar air dryer embedded with a delta-winglet vortex generator (DWVG). The present inquiry goal is to enhance the thermal performance of the solar air dryer. The delta-winglets were placed at the bottom absorber duct surface. Eight pairs of DWVG were considered for relative height (e/H) ratio from 0.2 to 0.6, an angle of attack (ß) was preserved at 60°, and the pitch-ratio (p/e) was equal to 10. This experimental investigation was performed for 0.022kg/s (MFR) and solar irradiance varied from (300 to 920) W/m2. The winglet vortex generators were set in a common flow-down configuration. The impact of (DWVG) on thermal efficiency and useful thermal energy was discussed. The thermal efficiency (η) and useful thermal energy (Qu) at 0.6 (e/H) appear improved up to about 6.5% and 9.4% respectively, higher than a smooth solar air dryer. The (DWVG) affects outlet air temperature, resulting in a considerable increase in the heat transfer convective rate.