Maximum delivery adiabatic hot-air engine

A maximum delivery adiabatic reciprocating hot-air engine, comprising:

• a. a minimal-sized chamber comprising:
• an interior space, a volume of working fluid, a first end, a second end positioned oppositely to said first end, a maximum interior chamber height extending from said first end to said second end along, a maximum interior chamber diameter, and an interior cross-sectional size decreasing incrementally from said chamber maximum interior diameter to said first end and to said second end, wherein said engine excludes a regenerator;
• b. a hot cap and a cold cap each comprising an inner shape, said hot cap positioned at said first end and said cold cap positioned at said second end, wherein said hot cap and said cold cap are characterized by a single wall between said volume of working fluid and a heat source or heat sink, respectively;
• c. a sealed isolator-displacer movable within said chamber between said hot cap and said cold cap, said isolator-displacer characterized by an exterior cross-sectional size that decreases incrementally from an isolator-displacer maximum diameter to each end thereof, wherein said isolator-displacer is also characterized by an outer shape that mates with said inner shape of said hot cap and said cold cap, wherein said isolator-displacer alternately displaces said volume of working fluid around said isolator-displacer between said hot cap and said cold cap while exposing said volume of working fluid to said hot cap when said isolator-displacer is at bottom dead center along said y-axis, and said isolator-displacer isolates said volume of working fluid from said hot cap while exposing said volume of working fluid to said cold cap when said isolator-displacer is at top dead center;
• d. a common space determined by an intersection of space in said chamber heated by said hot cap when said isolator-displacer is at bottom dead center or cooled by said cold cap when said isolator-displacer is at top dead center, said common space having a common space wall as an outer boundary;
• and
• e. a piston cylinder joined to said chamber at said chamber maximum interior diameter, wherein said volume of working fluid thermally communicates directly and with full effect against a piston through said opening.

A method of operating a maximum delivery reciprocating hot-air engine, comprising:

• a. providing a minimal-sized chamber comprising an interior space;
• a sealed isolator-displacer, a common space, a piston cylinder, and a piston, said chamber comprising a hot cap and a cold cap, and being configured to retain a volume of working fluid, said isolator-displacer and chamber being characterized by a wider diameter than ends, said isolator-displacer characterized by an exterior shape that mates with an interior shape of said hot and cold caps;
• b. compressing adiabatically said volume of working fluid to preheat said volume of working volume to an intermediate temperature equal to the square root of the product of a maximum and a minimum temperature;
• c. heating isochorically said volume of working fluid with said hot cap to a maximum interior temperature;
• d. expanding adiabatically said volume of working fluid to do work and precool said volume of working fluid to said intermediate temperature;
• and
• e. cooling isochorically said volume of working fluid with said cold cap to a minimum interior temperature, wherein said engine excludes a regenerator.