New Generation of Air Cooled Heat Exchanger 1 kW Module Design Optimization

The objective of this paper is to evaluate and optimize the performance of 1 kW integrated heat exchanger module for new generations of air cooled heat exchangers. The first objective is to minimize the ratio of the header frontal area to the entire heat exchanger frontal which will help to reduce the header size. The second objective is to minimize the pressure drop for the entire heat exchanger, i.e., inside the inlet and outlet headers in addition to pressure drop inside the tubes. A three step approach is proposed. First step involves selecting the header design based on previous header optimization studies and then simulating the header using a new 3D CFD simulation approach. Second step includes solving the heat exchanger using information from the header simulation that accounts for the variation in refrigerant mass flow rate inside the tubes and obtain the performance for the entire heat exchanger. Finally, a solver is used to evaluate the overall module performance. Three different headers are investigated with different header height and size ratio. Then parametric studies are conducted to explore the effect of header size ratio on the optimum designs. Lastly, design guidelines to optimize the integrated heat exchange module are provided based on the study results.