Accurately Simulating the Performance of Gasoline-Like Fuels in 1-D Hydraulic Injection System Models Operating at High Pressures 2021-01-0389

Recent research has shown that gasoline compression ignition (GCI) improves the soot-NOx tradeoff of traditional diesel engines due to the beneficial properties of light distillate fuels. However, system level optimization of a new engine concept is ultimately needed to maximize fuel economy and emissions improvements. Along with air and aftertreatment systems, the fuel system also requires further development to enable GCI. One important design tool for fuel system hardware is 1-D hydraulic modeling. Although accurate tabulations of diesel or equivalent calibration fluid properties are available in 1-D modelling software packages, the same situation does not exist for gasoline-like fuels, especially at conditions encountered in the high-pressure injection equipment needed to support GCI. This study presents a methodology for generating accurate liquid property databases of complex, multi-component light distillate fuels that can be used in high-pressure 1-D hydraulic models. The technique can be employed in situations where property tables do not exist in the software or when direct measurement data is unavailable across the conditions of interest. A typical single component surrogate for gasoline is shown to be ineffective at capturing the hydraulic behavior of a high-pressure injection system reaching 2500 bar. However, using the new methodology for generating liquid properties shows that a validated diesel injector model can easily be adapted to gasoline-like fuels with minimal recalibration of discharge coefficients. After this process, the 1-D model can reproduce experimentally measured injected quantities, injection rate shapes, hydraulic delays, and needle lift profiles for high-pressure, heavy-duty injectors operating with a light distillate fuel.