摘要 |
A gaseous fuel injection system for a cylinder of an internal combustion engine assures uniform mixing of the gaseous fuel with an air stream being inducted into the cylinder by injecting the gaseous fuel into the air stream at a relatively high velocity, preferably of between a Mach number of 0.5 and a Mach number of 1.0. High Mach injection can be achieved in a remarkably simple and effective manner by 1) using a single or at most a few injection conduit(s) and discharge orifice(s) for each intake port as opposed to a configuration having multiple discharge orifices at a single point in the air intake system upstream of the intake manifold, 2) by setting the relative effective flow areas of the injector metering orifice CdA1 and conduit discharge orifice CdA2 such that CdA2 is between 2 and 5 times greater than CdA1, and by 3) setting the gas supply pressure to be more than four times the air intake manifold absolute pressure. The resulting system is not only simpler and less expensive than supply systems having a high number of discharge orifices at a single upstream point, but also provides more uniform mixing and permits pulsating injection so that a stratified fuel charge can be supplied to the cylinders.
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