CAC Plumbing Lines Inner Medium Pressure Drop 1D Model Optimization

The Charge Air Cooler (CAC) is designed to cool the charge air after being boosted by the Turbocharger. In order to maintain the optimum temperature and to further improve the charge air density entering to the engine the CAC is used. This makes the combustion more efficient and better engine performance and fuel economy. The performance of the CAC is highly affected by the plumbing lines which transport the compressed charge air from turbocharger to the intake manifold of the Engine. It consists of tube, hose, duct and resonator. Designing the optimum CAC plumbing lines with lesser pressure drop is the major requirement of the CAC system considering the complex packaging. In such scenarios, one-dimensional (1D) simulation is a good way to compute the pressure drop for faster and economical solution. The approach of creating a modeling tool for CAC plumbing lines pressure drop prediction is discussed and the variables selected are hose, tube, resonator & duct friction factor and hose & tube bend surface roughness. Design for six sigma (DFSS) methodology is followed to create an L18 orthogonal array and iterations are created and 1D simulation is carried out using commercial software Flowmaster®. The inputs for the simulations are inlet pressure, temperature and different charge air mass flow rates to study the effect of pressure drop from low to high charge air mass flow rates. Samples parts are manufactured and tested in system bench test to validate the simulation results. This fine-tuned model shall be used to predict the CAC plumbing line pressure drop for the future programs with good accuracy.