Thermohydraulic Performance Optimization of Automobile Radiators Using Statistical Approaches

Automobile radiator which is one of the vital components used for engine cooling in vehicles is expected to provide higher thermal performance without changing the exterior dimensions of the radiator with the development of engine technology. This situation necessitates changes in both design and operating parameters in the currently used radiator. In the present study, all fundamental parameters affecting the thermal and hydraulic performance of an automobile radiator are evaluated and optimized with statistical methods. Optimization study is carried out using Taguchi and ANOVA methods for two specified objective functions (heat transfer and pressure drop). The order of importance and impact rates for each design and operating parameter, the best and worst working conditions in terms of both target functions are determined. Air velocity, air inlet temperature, coolant inlet temperature, and fin pitch are found to be the most effective parameters on the heat transfer with a contribution ratio of 88%. The best and worst working conditions are obtained for the heat transfer and under these working conditions, they are calculated as 43.68 kW and 1.63 kW, respectively. When the system is examined in terms of the pressure drop, the results show that the coolant flowrate and tube height have a great impact with a contribution ratio of 67.04% and 32.06%, respectively. Lastly, the maximum and minimum pressure drop within the studied operating condition range is determined as 20.68 kPa and 0.12 kPa, respectively.