Multi-fuel system and method

Abstract

A method provides for operating an engine configured to use a plurality of differing fuels. The method includes determining a fuel combustion ratio of the plurality of differing fuels associated with at least one engine cylinder of the engine based at least in part on one or more of a plurality of characteristic profiles. This maintains one or more of a plurality of actual values associated with usage of the plurality of differing fuels relative to defined corresponding threshold values. The fuel combustion ratio includes a ratio of the plurality of differing fuels to be delivered to the at least one engine cylinder. A fuel delivery system delivers the plurality of differing fuels to the at least one engine cylinder based on the fuel combustion ratio.

1 . A method for operating an engine configured to use a plurality of differing fuels, the method comprising:
 determining a fuel combustion ratio of the plurality of differing fuels associated with at least one engine cylinder of the engine based at least in part on one or more of a plurality of characteristic profiles along a defined path of a mobile asset in which the engine is disposed, wherein the fuel combustion ratio comprises a ratio of the plurality of differing fuels to be delivered to the at least one engine cylinder, and the plurality of characteristic profiles comprises one or more of global positioning sensor (GPS) information for a current location of the mobile asset, a calculated distance from the current location of the mobile asset to a fuel station, a fuel cost for one or more of the plurality of differing fuels, a terrain profile associated with a location on the defined path, or an ambient temperature or ambient pressure proximate to the mobile asset; and   controlling a fuel delivery system to deliver the plurality of differing fuels to the at least one engine cylinder based on the determined fuel combustion ratio.   
     
     
         2 . The method of  claim 1 , where the plurality of characteristic profiles comprises two or more of the GPS information for the current location of the mobile asset, the calculated distance from the current location of the mobile asset to the fuel station, the fuel cost for one or more of the plurality of differing fuels, the terrain profile associated with the location on the defined path, or the ambient temperature or ambient pressure proximate to the mobile asset. 
     
     
         3 . The method of  claim 1 , wherein the plurality of characteristic profiles comprises at least one asset sensed information comprising at least one of an engine emission level, a fuel usage level, a power output, an engine load, an engine speed, or a fuel injection profile. 
     
     
         4 . The method of  claim 1 , further comprising controlling a measured exhaust emission constituent level relative to a defined threshold emission level. 
     
     
         5 . A method for operating an engine configured to use a plurality of differing fuels, the method comprising:
 monitoring a plurality of engine parameters;   determining a fuel combustion ratio of the plurality of differing fuels associated with at least one engine cylinder of the engine based at least in part on one or more monitored engine parameters and one or more of a plurality of characteristic profiles along a defined path of a mobile asset in which the engine is disposed, wherein the fuel combustion ratio comprises a ratio of the plurality of differing fuels to be delivered to the at least one engine cylinder, and the plurality of characteristic profiles comprises one or more of global positioning sensor (GPS) information for a current location of the mobile asset, a calculated distance from the current location of the mobile asset to a fuel station, a fuel cost for one or more of the plurality of differing fuels, a terrain profile associated with a location on the defined path, or an ambient temperature or ambient pressure proximate to the mobile asset; and   controlling a fuel delivery system to deliver the plurality of fuels to the at least one engine cylinder based on the determined fuel combustion ratio.   
     
     
         6 . The method of  claim 5 , wherein one of the one or more monitored engine parameters comprises an increased load operation of the engine. 
     
     
         7 . The method of  claim 6 , wherein the increased load operation comprises a transient acceleration operation. 
     
     
         8 . The method of  claim 6 , further comprising determining if an increased load operation corresponds to an increased gradient of the defined path at the current location of the mobile asset. 
     
     
         9 . The method of  claim 8 , further comprising determining in advance that an increased gradient is coming up along the defined path and pre-staging the engine to anticipate the increased load. 
     
     
         10 . The method of  claim 9 , wherein the pre-staging includes switching hardware configurations comprising one of a valve event, compression ratio, piston, piston ring, valve lift profile, pressure sensor, temperature sensor, knock sensor, injector, or injector nozzle. 
     
     
         11 . The method of  claim 9 , wherein one of the one or more monitored engine parameters comprises an aftertreatment status. 
     
     
         12 . The method of  claim 6 , wherein one of the one or more monitored engine parameters comprises a sensor status for a temperature sensor or a knock sensor. 
     
     
         13 . The method of  claim 6 , wherein one of the one or more monitored engine parameters comprises increased engine speed. 
     
     
         14 . A fuel system, comprising:
 a fuel controlling unit configured to deliver a plurality of differing fuels to at least one engine cylinder of an engine based at least in part on a fuel combustion ratio,   wherein the fuel combustion ratio comprises a ratio of the plurality of differing fuels to be delivered to the at least one engine cylinder and is based at least in part on one or more of a plurality of characteristic profiles along a defined path of a mobile asset in which the engine is disposed, wherein the fuel combustion ratio comprises a ratio of the plurality of differing fuels to be delivered to the at least one engine cylinder, and the plurality of characteristic profiles comprises one or more of global positioning sensor (GPS) information for a current location of the mobile asset, a calculated distance from the current location of the mobile asset to a fuel station, a fuel cost for one or more of the plurality of differing fuels, a terrain profile associated with a location on the defined path, or an ambient temperature or ambient pressure proximate to the mobile asset.   
     
     
         15 . The system of  claim 14 , further comprising one or more sensors operable to communicate sensor information with the fuel controlling unit sensor information, and the fuel controlling unit is operable to receive the sensor information and thereby to determine the one or more of the plurality of characteristic profiles. 
     
     
         16 . The system of  claim 14 , wherein the fuel controlling unit is configured to signal a fuel demand to a regasification unit to supply at least one of the plurality of fuels. 
     
     
         17 . The system of  claim 14 , wherein the fuel controlling unit is configured to maintain an actual quantity of at least one of the plurality of differing fuels in the mobile asset to less than or equal to a defined threshold quantity for that fuel. 
     
     
         18 . The system of  claim 14 , wherein the plurality of characteristic profiles further comprises one or more of historical operational data or ambient conditions along the defined path. 
     
     
         19 . The system of  claim 14 , wherein the mobile asset in which the engine is disposed is a vehicle. 
     
     
         20 . The system of  claim 19 , wherein the vehicle is a rail vehicle, and the plurality of differing fuels include diesel and natural gas.