Thermodynamic Study of the Main Characteristics of a Constant Volume Combustion Gas Turbine

Modern gas turbine aircraft engines operate following the classic Brayton cycle, which consists of a thermodynamic cycle with constant pressure combustion. However, at the beginning of the last century, some gas turbine engines were built following the Humphrey thermal cycle, whose main characteristic is the constant volume combustion. The advantage of this cycle is given by the combustion process, which taking place in a closed volume allows the maximum pressure of the cycle to be greatly increased without the need for a large amount of compression work. This fact has obvious repercussions on the maximum achievable thermodynamic efficiency. Recent studies suggest the possibility of integrating a conventional gas turbine engine with a constant volume combustor, seeking to increase thermal efficiency. In this work, through a thermodynamic numeric program that solves the cycle and calculates its main characteristics, an analysis of a gas turbine engine with constant volume combustion is performed, and a comparison is made with the main performances and efficiencies of the conventional gas turbine cycle.