Characteristics of a closed Brayton cycle piston engine

The author describes an all-fuel engine for use in vehicles and in other applications such as providing power for irrigation pumps and auxiliary electric generators. Potential fuels for this engine include not only the usual high-grade fuels but also low-grade fuels such as coal, straw, wood, or any other form of biomass. The coal of biomass need not be processed, i.e., converted to a higher grade; it can be used as is. An engine of this kind can facilitate the substitution of domestic and/or renewable fuels for petroleum-based fuel. It can have a major impact on agriculture in two ways: first, by increasing the market for biomass fuel, and second, by making it economical to use biomass fuel in farm machinery. In particular, because the fuel can be low grade the entire plant, or any fraction thereof, can be used if desired. Moreover, after harvesting no additional energy input is needed to convert it into fuel. As a result, the net useful energy yield per acre is much increased