Internal combustion engine with cooling of intake air using refrigeration of liquefied fuel gas

A locomotive interned combustion engine adapted to be fueled at least partially with a liquefied gaseous fuel supplied and vaporized from an accompanying storage vessel containing the liquefied gaseous fuel at pressures below about 200 psig (14 bar-g), said locomotive internal combustion engine comprising an internal combustion engine capable of being operated on a gaseous fuel that can be stored as a liquid at an ambient or subambient temperature while at pressures below about 200 psig (14 bar-g) and which, on expansion to the pressure for injection as fuel into the internal combustion engine, can achieve adiabatic temperatures of below about 50.degree. F. (10.degree. C.);

• means for compressing combustion intake air;
• a first compressed combustion intake air aftercooler for cooling the compressed combustion intake air against an ambient coolant;
• means for receiving vaporized gaseous fuel from a cold fuel heat exchanger for indirect heat exchange between the liquid fuel and a warmed intermediate circulating coolant wherein heat transferred from the warmed intermediate circulating coolant lowers the temperature of the warmed intermediate circulating coolant to produce a chilled intermediate circulating coolant and warms the liquid fuel to produce the vaporized gaseous fuel;
• means for conducting the vaporized gaseous fuel to the combustion chambers of the internal combustion engine;
• means for conducting the chilled intermediate circulating coolant from the cold fuel heat exchanger to a second intake sir compressor aftercooler wherein the chilled intermediate circulating coolant is indirectly heat exchanged against the compressed combustion intake air to produce a chilled compressed combustion intake air charge and a warmed intermediate circulating coolant;
• and means for conducting the warmed intermediate circulating coolant back to the cold fuel heat exchanger.

In an internal combustion engine fueled with a fuel gas vaporized from a liquefied gaseous fuel and having means for compressing the combustion intake air and an aftercooler for cooling the compressed combustion intake air against an ambient coolant source, and additional means for effecting heat exchange between the liquefied gaseous fuel and compressed combustion intake air whereby heat is removed from the compressed combustion intake air and said heat is transferred to the liquefied gaseous fuel, the improvement wherein said heat exchange means for effecting heat exchange between the liquefied gaseous fuel and the compressed combustion intake air comprises a cold fuel heat exchanger for indirect heat exchange between the liquefied gaseous fuel and a warmed intermediate circulating coolant wherein heat transferred from the warmed intermediate circulating coolant to the liquefied gaseous fuel lowers the temperature of the warmed intermediate circulating coolant to produce a chilled intermediate circulating coolant and warms the liquefied gaseous fuel to produce a warmed fuel;

• means for conducting the liquefied gaseous fuel to the cold fuel heat exchanger;
• means for conducting the warmed fuel to the combustion chambers of the internal combustion engine;
• means for conducting the chilled intermediate circulating coolant from the cold fuel heat exchanger to the intake air compressor aftercooler wherein the chilled intermediate circulating coolant is indirectly heat exchanged against the compressed combustion intake air to produce a chilled compressed combustion intake air charge and a warmed intermediate circulating coolant;
• and means for conducting the warmed intermediate circulating coolant back to the cold fuel heat exchanger, the intermediate circulating coolant being contained in a closed intermediate circulating coolant loop separate from the ambient coolant source.

In an internal combustion engine fueled with a fuel gas vaporized from a refrigerated liquid fuel and having means for compressing the combustion intake air and an aftercooler for cooling the compressed combustion intake air against an ambient coolant source, and additional means for effecting heat exchange between the refrigerated liquid fuel and compressed combustion intake air whereby heat is removed from the compressed combustion intake air and said heat is transferred to the refrigerated liquid fuel, the improvement further comprising means for conducting the refrigerated liquid fuel to a subcooler wherein the refrigerated liquid fuel is cooled below its saturation temperature to produce a subcooled liquid fuel;

• means for drawing off a sidestream of the subcooled liquid fuel and expanding and flashing the sidestream of subcooled liquid fuel to produce a further cooled flashed vapor;
• means for indirectly heat exchanging the cooled flashed vapor in the subcooler with the refrigerated liquid fuel;
• a pump for raising the pressure of the subcooled liquid fuel to produce a high pressure refrigerated liquid fuel;
• means for conducting the subcooled liquid fuel from the subcooler to the pump;
• and means for conducting the high pressure refrigerated liquid fuel from the pump to the heat exchange means for effecting heat exchange between the refrigerated liquid fuel and the compressed combustion intake air which comprises a cold fuel heat exchanger for indirect heat exchange between the high pressure refrigerated liquid fuel and a warmed intermediate circulating coolant wherein heat transferred from the warmed intermediate circulating coolant to the high pressure refrigerated liquid fuel lowers the temperature of the warmed intermediate circulating coolant to produce a chilled intermediate circulating coolant and warms the high pressure refrigerated liquid fuel to produce a vaporized fuel;
• means for conducting the high pressure refrigerated liquid fuel to the cold fuel heat exchanger;
• means for conducting the vaporized fuel to the combustion chambers of the internal combustion engine;
• means for conducting the chilled intermediate circulating coolant from the cold fuel heat exchanger to the intake air compressor aftercooler wherein the chilled intermediate circulating coolant is indirectly heat exchanged against the compressed combustion intake air to produce a chilled compressed combustion intake air charge and a warmed intermediate circulating coolant;
• and means for conducting the warmed intermediate circulating coolant back to the cold fuel heat exchanger.