Inhalt des Dokuments
2nd Law analysis of the expansion process in constant volume combustors and cycles
The introduction of constant volume combustion in gas turbine cycles offers a high potential for net efficiency increase. The expansion process of the cycle is divided in two sub-processes, one taking place in the combustor and the second in the turbine. The former generates no actual work but is substantial for the whole process because it provides the driving force that empties the combustor from its contents before the next combustion period may commence. While the expansion irreversibilities of the turbine expansion can be captured by polytropic efficiencies, the expansion in the combustion chamber is traditionally considered isentropic. This assumption introduces errors in the efficiency calculations for the whole cycle.
Aim of the current thesis is the quantification of these losses and the estimation of their effect on the efficiency of gas turbine cycles with constant volume combustion.
Aims and tasks
- An existing computational code for the gas dynamic phenomena in CVC combustion chamber will be adapted to compute the losses during the expansion in the combustion chambers
- The effect of these losses in the cycle efficiency will be estimated for Pulsed detonation combustion, shockless explosion combustion and rotating detonation combustion
- Knowledge of gas turbine thermodynamics and gas dynamics
- Previous experience with Matlab is necessary
- Experience with second law analysis of thermodynamic cycles is of advantage.