PERFORMANCE OF A GAS-TURBINE ENGINE USING 2 METHODS OF CONTROL

To reduce the inefficiency and the drawbacks incurred by reheat in a gas turbine engine with the two turbines in series, a parallel arrangement is investigated. The combustion gases expand to atmospheric pressure in each turbine. Two methods of control for the reduction of power are considered: (a) Varying the fuel supply to the combustion chambers so that the inlet temperature to the turbine driving the compressor is constant, while the inlet temperature to the power turbine is reduced; (b) Reducing both temperatures while keeping them equal. The effects of the turbines' inlet temperatures, pressure ratio and pressure loss in combustion chambers on the cycle efficiency and power output are studied and a sensitivity analysis is carried out, with the aid of a specially constructed computer program. The first method of control proved to be superior.