FIELD: mechanical engineering; internal combustion engines. SUBSTANCE: proposed internal combustion engine has two cylinder- piston groups, each including reduced diameter piston in corresponding cylinder whose reduced volume provides creating of not more than 90% value of designed compression ratio of air-fuel mixture in combustion chamber. Engine uses for its operation a new method of compression of air-fuel mixture by reduced diameter piston and compressor to designed value of compression ratio of air-fuel mixture in combustion chamber. New method of use of high-pressure hot gases is employed in engine. High-pressure hot gases act onto reduced diameter piston accommodated in reduced volume cylinder which provides fuel economy as gas pressure drop per unit of piston stroke from TDC to BDC in reduced diameter cylinder is less than that in standard engine. EFFECT: reduced fuel consumption at the same power output. 3 cl, 1 dwg
