Thermal to mechanical energy conversion process - using e.g. liq. carbon di:oxide with waste heat recycling

摘要

A process for converting thermal energy into useful mechanical energy employs a liq. work medium, e.g. CO2, in a cyclic process consisting of two polytropes (1-2,3-4) and two isochores (2-3,4-1) as shown on the temp. vs. entropy graph. The cycle pref. consists of a first line (1-2) of adiabatic compression in which the CO2 temp. drops, an isochore (2-3) of heat supply for pressure increase, a line (3-4) of adiabatic expansion under working load in which the CO2 temp. increases and a final isochore (4-1) of waste heat extraction to attain the initial pressure. The extracted waste heat is pref. completely or partially returned to the isochore region (2-3). USE/ADVANTAGE - The process is used in engines, esp. heat engines, and allows return of waste heat to the circuit.