Improving Radiator Design Through Shape Optimization

The current emphasis by auto manufacturers on improving the quality and fuel economy of their vehicles requires enhancements in the efficiency and operation of all engine components, including those in the engine cooling system. Improvements in the pressure drop and flow homogeneity in the water tank of a radiator are needed to reduce the power demands on the vehicle water pump and increase the lifetime of the radiator. The latter criterion is particularly important in the reduction of premature fouling and failure of heat exchangers. Rather than relying on ad hoc geometry changes with the goal of improving the performance of radiators, the coupling of CFD flow simulations with numerical shape optimization methods could assist in the design and testing of automotive heating and cooling components. This paper describes ongoing efforts to develop a fully automated suite of virtual tools to aid in the design and testing of automotive heating and cooling components. The development and validation of optimization criteria for pressure drop and mass flow rate distribution in a water-to-air automotive heat exchanger are discussed, as well as the methodology used to automate the mesh generation, CFD simulation, and shape optimization procedures using the GAMBIT^® and FLUENT^® software combined with an in-house code.