PERFORMANCE ENHANCEMENT OF SOLAR AIR HEATER USING ARC-SHAPED PERFORATED BAFFLES

Abstract

Energy consumption is growing tremendously in each corner of the world due to economic expansion, and changes in mankind's lifestyles and transportation. Although the usage of fossil fuels is suitable to fulfill such energy needs, environmental issues and respiratory problems in humans are key challenges to thinking about alternative energy resources. As a result, the world needs to prioritize now to convert our energy systems and speed up the transition to net-zero carbon emission systems. Out of all renewable energy resources, solar energy is limitless, environmentally friendly, and abundant in nature, it can be a crucial resource for sustainable development. It is therefore, research on the progress of solar energy exchange devices like solar collectors employed for the collection of solar energy is enhancing rapidly in the past two decades. The most common and affordable solar energy collector arrangement is the solar air heater (SAH), This technology harnesses the energy from the sun and transforms it into thermal energy via the utilization of absorber plates. SAH applications can be seen in domestic and industrial applications. However, the coefficient of heat transfer between the air and the absorbing plate is low because of viscous sublayer on an absorber plate which results in low thermo-hydraulic performance(THPP). Consequently, many research studies have been conducted to enhance the efficiency of the system by implementing different inventive methods such as artificial roughness and jet impingement. According to the thorough literature research, it has been established that introducing surface roughness to an absorber plate proves to be an effective approach in enhancing transfer of heat in duct. Keeping this in view, in the present study, the arc-shaped perforated baffles artificial roughness technique was proposed in SAH to investigate its performance through the computational fluid dynamics (CFD) approach. The accepted CFD methodology is a trustworthy and effective tool for looking into and analysing the performance of SAH, according to numerical results that have been validated with published results. Moreover, the outcome of diverse system parameters, including relative roughness pitch (P/e) and relative blockage height(e/D), on the Nusselt number(Nu) and friction factor(f) of the SAH under different operating conditions has been investigated. These parameters are optimized based on the results obtained from the thermal-hydraulic performance (THPP) analysis.