Method and system for delivering gaseous fuel into an intake system of an internal combustion engine

Abstract

Disclosed herein is a method and system for delivering cryogenically stored fuel in a gaseous state into an intake system of a gas internal combustion engine. The method includes determining a flow rate capability in a fuel delivery line of the engine system, comparing the determined flow rate capability to a desired flow rate requirement, and when the flow rate capability is at or above the specified Fuel in a gaseous state is supplied directly from the vapor space of the cryogenic storage vessel to the fuel delivery line that supplies fuel to the engine when the desired flow rate is required. The method further includes activating a cryopump to deliver fuel from a liquid space of the cryogenic storage vessel to the internal combustion engine when the determined flow rate capability is lower than the desired flow rate requirement.

Description

technical field [0001] The present disclosure relates to methods and systems for delivering cryogenically stored fuel into the intake system of a gas internal combustion engine. Background technique [0002] A fuel storage and delivery system for an internal combustion engine that is powered with a gaseous fuel, such as natural gas, is one example of an application that is particularly suited for the disclosed method and system. Natural gas has been used to fuel vehicle engines for many years. Fuel supplied to natural gas powered vehicles is stored in liquefied natural gas (LNG) tanks or compressed natural gas (CNG) cylinders. [0003] CNG is typically stored at ambient temperatures at pressures up to 3600 psig, while LNG is typically stored at temperatures between about -240°F and -175°F (about -150°C and -115°C) and between 15 psig and 200 psig Store in cryogenic storage containers under pressure. CNG has been the more widely adopted form of fuel storage, but has a lowe...

AI Technical Summary

Problems solved by technology

[0009] A disadvantage of using a pressure build-up circuit to pressurize a cryogenic fluid storage vessel is that the heat used to generate the vapor that is supplied to the headspace of the storage vessel to pressurize it is also transferred to the liquid contained in the vessel, thereby Decreases the fluid hold time of the container and requires more frequent drains

[0010] Another disadvantage of existing low pressure fuel supply systems that rely on fuel saturation pressure in a storage vessel to supply fuel to the engine is that when the required fuel supply pressure varies between the lower pressure required for low load operation and the higher They cannot adequately fuel the engine during transient conditions when dynamically changing between the higher pressures required for load operation

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