METHOD OF OPERATING THERMAL ENGINE AND ITS DESIGN Russian patent published in 2009 - IPC F02B47/02 F02B53/02 F02B55/16 F01C1/356 

FIELD: engines and pumps.

SUBSTANCE: invention relates to engine production. Method of operating thermal engine comprises intake of fuel-air mix or air in first stroke, compression and ignition in second stroke, combustion of aforesaid fuel-air mix and injecting water into working chamber in third stroke, and displacement of combustion products and steam in fourth stroke. Thermal engine features variable-volume tight working chambers, including main combustion chamber and piston. It comprises also combustion chamber prechamber whereto water is injected in third stroke. Amount of injected water is adjusted depending upon gas pressure in injection and engine shaft RPM. Forced-in fuel-air mix or air is throttled. Volume of compressed fuel-air mix or air is varied. Water is injected after combustion of the main portion of combustible mix is completed. Combustion products and steam are displaced at minimum pressure at temperature, e.g. 1 to 5 atm and 100°C to 500°C. Tight chambers of the engine are thermally insulated from ambient air.

EFFECT: higher efficiency reduced harmful emissions and exhaust temperature.