Comparison of Heat Transfer in Elliptical Ducts with Circular and Square Ducts in Transient State

Many geometrical and experimental methods were proposed to enhance heat transfer in a heat exchanger. This paper emphasizes improving heat transfer in elliptical ducts compared to conventional circular, square ducts. Simulation results using Ansys showed that the length of the duct required to obtain the desired temperature difference for elliptical ducts is lesser than that for circular and square ducts. The energy balance method was used to obtain differential equations solved using MATLAB. Simulated results in Ansys Fluent were reported for the ducts under consideration. Fluid in the ducts is of high temperatures, where the mode of heat transfer through radiation is substantial. For elliptical ducts, temperature gradient vs. aspect ratio and temperature gradient vs. time at constant aspect ratio graphs were plotted. The maximum pressure for elliptical ducts was 0.362 bar, whereas, for circular and square ducts, it was observed to be 0.3801 bar and 0.4978 bar. The maximum temperature for the elliptical ducts was observed to be 372.4 K.