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Evaporative cooling is a very common form of cooling buildings for thermal comfort since it is relatively cheap and requires less energy than many other forms of cooling. However evaporative cooling requires an abundant water source as an evaporate, and is only efficient when the relative humidity is low, restricting its effective use to dry climates. Traditionally, evaporative cooler pads consist of excelsior (wood wool) inside containment net. Padding media plays a large part in cooling efficiency and water consumption. This paper investigate a performance of Desert Cooler using four different pad materials in terms of cooling efficiency ,water consumption and air velocity. Pads of Stainless steel wire mesh, coconut coir, Khus and Wood wool were fabricated and tested using a laboratory-scale experimental arrangement. Maximum water consumption was observed in wood wool pad (0.24 Lit/min). Coconut coir (0.134 Lit/min) and Khus pad (0.21 Lit/min) also shown less water consumption rate as compared to conventional wood wool pad. Minimum water consumption was observed in Stainless steel wire mesh pad (0.066 Lit/min) at same fan speed. Stainless steel wire mesh pad (4.5 m/s) and coconut coir pad (5.2 m/s) shown higher air velocity which provides proper air distribution in room while Wood wool pad (4m/s) and Khus pad (3.4 m/s) were shown lower velocity. Maximum and minimum cooling efficiency were found in wood wool pad and Stainless steel wire mesh pad.

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The performance of heat transfer enhancement (HTE) using modified inserts (MIs) as a vortex generator in pipe flow and fluid flow analysis using computational fluid dynamics (CFD) are evaluated in this article. The MIs are fastened to the central rod, and the circular sections of the MIs touched the circular wall of the test pipe. Heat transfer and fluid flow analyses are carried out for the various pitch to diameter ratios (P/D) and angles of the MIs. P/D ratios of 3, 4 and 6 and MIs angles of 15°, 30°, 45°, 60° and 90° are considered for experimental analysis. CFD analysis is carried out for P/D ratios of 3, 4 and 6 and MIs angles of 30°, 45° and 90°. Nusselt number (Nu/Nus) and friction factor (f/fs) ratios are evaluated using the same Reynolds number between 8000 and 17,000 in the experimental study. The MIs encourage the wall and core fluid to be combined thus helps in HTE. It is found that, as the P/D ratio increases, the Nu/Nus and f/fs decrease. If the distance between the MIs increases, the mixing of fluid weakens. With decreasing the P/D ratio, Nu/Nus increases. Increased fluid mixing leads to a higher coefficient of heat transfer and higher values of pressure drop. A P/D ratio of 4 and MIs angle of 45° results in greater heat interaction than others. Finally, recommendations for the best P/D ratio and angles of MIs are made for improved HTE on fluid flow through a circular pipe. Article Highlights Modified inserts (MIs) are used inside the test pipe to check the heat transfer enhancement at various angles. Also, compared the performance with and without MIs. Fluid flow analysis is checked by CFD (Fluent) in Ansys software. Fluid flow patterns for various MIs angles and P/D ratios are compared.