The passenger class automobiles operating with gasoline direct injection (DI) pump have a better fuel economy than the automobiles operating with gasoline port fuel injection (PFI) pump. The fuel economy is higher because DI pump injects fuel directly into combustion chamber at pressures over 150 bar compared to a PFI pump which injects fuel into combustion chamber through inlet port at pressures over 50 bar. By injecting fuel directly into the combustion chamber, DI system prevents condensation of fuel, pressure leakage and improves atomization of fuel for internal combustion process. However, the disadvantage of high pressure operation is that the DI pump is noisier than a PFI pump. The loud sound in a DI pump is generated due to phenomenon such as high pressure pulsations, liquid jet impact and high velocity flows. To investigate the sound production in a DI pump, High fidelity hybrid numerical simulations were developed using CFD and Acoustic tools to simulate the operational effects and identify the behavior of internal components of DI pump. The fidelity of the numerical simulations depends on the transient boundary conditions and the fluid structure interactions in the DI pump. The CFD simulation model of DI pump has 8 million mesh elements and the simulation model is computed using 256 cores of super computer operating at a rate of 2 TFLOPS. The results derived from the CFD simulations were processed using a commercial acoustics tool for computing sound pressure level in liquid domain. Sound pressure level in liquid domain is used as a relative parameter for distinguishing the behavior of liquid-acoustic sources. The results from the numerical simulations provide a good account of the behavior of internal components in DI pump and the simulation results are in good agreement with the experiments performed on DI pump.

This content is only available via PDF.
You do not currently have access to this content.