FIELD: converting heat energy to mechanical work. SUBSTANCE: heated working fluid, obtained during burning of fuel with oxygen and supplied to turbine upstream of it, is expanded and swirled with respect to the longitudinal axis of the gas-turbine engine. The heated working fluid is mixed with exhaust gas downstream of the turbine to obtain a flow of heated fluid with changed thermodynamic condition and to introduce it then in the turbine for expanding and doing useful work. A part of the heated working fluid with changed thermodynamic condition is introduced from the flow part of the turbine before introducing of the heated working fluid with changed thermodynamic condition. The gas-turbine engine has turbine, source of heated working fluid, ejector whose first inlet is coupled with the source of heated working fluid, second inlet is connected to the turbine outlet, and outlet is connected to the inlet of the turbine. The ejector has the second outlet connected to the atmosphere. EFFECT: enhanced efficiency. 3 cl, 9 dwg
