Application of thermodynamic laws on a military helicopter engine

By definition, a turboshaft engine is simply a gas turbine used to deliver shaft power such as to a helicopter rotor. This paper presents the energetic and exergetic analyses of a turboshaft engine which is used for military helicopter at various load values. The main objectives of this study are to assess the performance of the engine and to calculate the amount of exergy destructions in the components of the engine. The calculations were performed at four different load values (284 N·m for test #1, 436 N·m for test #2, 547 N·m for test #3 and 579 N·m for test #4) and all analyses were performed and presented on the basis of the experimental engine ground test data together with a theoretical thermodynamic performance evaluation. The exergetic performance parameters, such as the relative exergy destruction, the fuel depletion ratio, the productivity lack, the improvement potential were also investigated. The exergy destruction values for the combustion chamber, which has the highest exergy destruction among all the components, were calculated as 1170.30 kW, 1474.50 kW, 1650.12 kW, and 1702.50 kW for tests #1, #2, #3 and #4, respectively. In addition, the ratio of the exergy destruction to the total exergy destruction was obtained to be the highest in the combustion chamber (88.81%) at test #2; whereas this ratio was found to be the lowest in the high-pressure turbine (0.75%) at test #2.