Abstract: A fuel mixer includes a first compartment, a second compartment, a third compartment, a plurality of cooling tubes, and at least one flow pipe. The second compartment is in fluid communication with the first compartment and is at least partially above the first compartment. The third compartment is in fluid communication with the first compartment and is at least partially above the first compartment. The plurality of cooling tubes are disposed in the second compartment and extend between the first compartment and the third compartment, thereby allowing fuel to flow from the first compartment to the third compartment. The at least one flow pipe is disposed in the second compartment and has an open top end, thereby allowing fuel to flow from the second compartment to the first compartment.

Abstract: A refueling system includes a first fuel source, a second fuel source, and a fuel source selection device. The fuel source selection device includes a fuel mixer comprising a mixing chamber, a first inlet in fluid communication with the mixing chamber and configured to be fluidly coupled to an engine, a second inlet in fluid communication with the first fuel source and the mixing chamber, a third inlet fluidly coupled to the second fuel source, a first outlet in fluid communication with the engine and the mixing chamber, and a second outlet fluidly coupled to the second fuel source. The fuel mixer is configured to operate in a first mode or a second mode. In the first mode, fuel passes from the first fuel source to the engine. In the second mode, fuel passes from the second fuel source to the engine.