What is the role of the combustor in a gas turbine engine?

The combustor in a gas turbine engine serves a critical function by mixing fuel with compressed air and initiating combustion. This process is essential for converting the chemical energy stored in the fuel into thermal energy, which subsequently expands the gases. The combustion process raises the temperature and pressure of the gases, creating a high-energy stream that flows through the turbine, where it is further used to produce mechanical energy for propulsion or to drive other components of the engine.

While cooling the engine assembly is an important aspect of overall engine design, it is not the primary role of the combustor. Similarly, the expansion of gases for propulsion occurs downstream in the turbine section, not in the combustor itself. Additionally, the combustor does not function as a fuel storage unit; fuel is delivered directly from fuel tanks to the combustor for combustion. Thus, the correct identification of the combustor's role as initiating combustion emphasizes its importance in the overall gas turbine operation.