Influence of Water Injection on Knock of Hydrogen Engine
Hydrogen has characteristics such as low ignition energy and a wide ignition limit,making it prone to abnormal combustion phenomena such as detonation.Injecting water into the intake manifold is an effective means to mitigate engine knock.Using CONVERGE software,a model of a hydrogen fuel direct injection(GDI)engine with a cylinder diameter of 92mm was analyzed.Water was injected into the intake manifold at rates of 10mg and 20mg,and the combustion characteristics and knock index of the engine were studied.The results in-dicate that under both 10mg and 20mg water injection conditions,near top dead center,the fluctuation in cylin-der pressure decreases continuously,cylinder temperature transition becomes smoother,and the peak heat re-lease rate reduce from two peaks to one.The knock evaluation parameter MAPO decreases from 0.186 MPa to 0.038 MPa and 0.006 MPa respectively under the two water injection conditions,demonstrating that water injection technology can effectively suppress knock in hydrogen-fueled engines.
NETL
NSTL
万方数据
