In-Cylinder Dynamic Gas Blending Fuel Injector And Dual Fuel Engine

摘要

A dual fuel engine utilizes a compression ignited pilot injection of liquid diesel fuel to ignite a mixture of gaseous fuel and air in each engine cylinder. The gaseous fuel is injected at a relatively low pressure directly into the engine cylinder from a fuel injector. The liquid diesel fuel is injected directly into the engine cylinder from the same fuel injector. In-cylinder dynamic gas blending during the compression stroke can reduce potential hydrocarbon slip that could occur when unburned fuel resides in crevice volumes within the engine cylinder.

主权项

1. A dual fuel engine comprising:
an engine housing defining a plurality of cylinders; a plurality of fuel injectors, each having an injector body that defines a liquid nozzle outlet set and a gaseous nozzle outlet set that open into one of the cylinders, and defines a liquid fuel inlet, a gaseous fuel inlet and a drain outlet, and including a liquid needle valve member that opens and closes the liquid nozzle outlet set, and a gaseous needle valve member that opens and closes the gaseous nozzle outlet set, and including a first electrical actuator operably coupled to the liquid needle valve member, and a second electrical actuator operably coupled to the gaseous needle valve member; a high pressure liquid fuel common rail fluidly connected to the liquid fuel inlet of each of the fuel injectors; a low pressure gaseous fuel common rail fluidly connected to the gaseous fuel inlet of each of the fuel injectors; a drain line fluidly connected to the drain outlet; and each of the fuel injectors includes a drain annulus that surrounds the gaseous needle valve member, and is fluidly connected to the drain outlet.