Enhancement of Heat Exchanger Performance Using Oscillatory Flow Phenomena 2020-01-0943
In this research work, the heat transfer enhancement by using oscillatory flow of thermal fluid between cold and hot reservoir has been analyzed both theoretically and using simulation methods. The main objective of this study is to examine the feasibility of a system working under oscillatory flow conditions compared to its steady flow counterpart. The principle of incrementing thermal diffusion over molecular diffusion by establishing oscillatory flow has been utilized in this case. The system has been designed and the effect of the flow condition has been analyzed using ANSYS Fluent k-epsilon model. A temperature gradient of 50 K has been successfully obtained using the oscillatory flow condition for the assumed capillary dimension of 48 mm. The effect of change in the magnitude and frequency of oscillation on local Nusselt number has been computed. The observed increment in the Nusselt number by increasing the amplitude and frequency of the fluid has been bolstered by analytical calculation. A comparison in the heat transfer of a system working under oscillating and a steady flow conditions has been generated to establish the need for oscillating flow. The scope of the study has been extended to explore possibility of implementation of this concept in the automotive HVAC system and in the cooling mechanisms employed in microelectronic components present onboard e-vehicles.
keywords: oscillatory flow, thermal diffusion, simulation method, heat transfer enhancement.