How is reheat accomplished in a gas turbine?

Reheat in a gas turbine is accomplished by heating the gases between the high-pressure (HP) turbine and the low-pressure (LP) turbine. This process involves extracting energy from the exhaust gases generated by the HP turbine and using it to heat the working fluid (the exhaust gases) before it enters the LP turbine.

This reheating increases the temperature and energy of the gases entering the LP turbine, allowing for a higher efficiency of the cycle. By raising the temperature of the exhaust gases again before they enter the LP turbine, it facilitates the extraction of additional work output, thereby enhancing the overall performance of the gas turbine system. This method of reheat is crucial because it helps improve the thermodynamic efficiency and power output of the turbine, contributing to a more effective energy generation process.

Other choices do not accurately capture the specific process of reheat as it pertains to the gas turbine cycle. For instance, heating the air between the HP compressor and HP turbine or after the LP compressor does not refer to the classic reheat method which specifically targets the gases post-HP turbine for efficiency optimization.