Dual fuel common rail system and diesel only method of operating same

摘要

A dual fuel common rail system may be operated in a regular mode in which a relatively large charge of gaseous fuel is ignited by compression igniting a relatively small injection quantity of liquid diesel fuel. The dual fuel system may be operated in a single fuel limp home mode in which liquid diesel fuel is injected at higher pressures. Over pressurization of the gaseous fuel side of the fuel system due to leaked liquid fuel is avoided by regularly injecting leaked liquid fuel, but not gaseous fuel, from the gaseous nozzle outlet set during the limp home mode of operation.

主权项

1. A method of operating a dual fuel engine, comprising the steps of:
operating a dual fuel common rail system in a regular mode; operating the dual fuel common rail system in a limp home mode; leaking more liquid fuel into a gaseous fuel portion of the dual fuel system when operating in the limp home mode versus the regular mode; injecting liquid fuel from a first nozzle outlet set and injecting gaseous fuel from a second nozzle outlet set into an engine cylinder when operating the dual fuel common rail system in the regular mode; injecting liquid fuel from the first nozzle outlet set and injecting liquid fuel, but not gaseous fuel, from the second nozzle outlet set into the engine cylinder when operating the dual fuel common rail system in the limp home mode.