How much would the thermal efficiency of the cycle in Prob. 9-124 change if the temperature of the cold-air stream leaving the regenerator is 808C lower than the temperature of the hot-air stream entering the regenerator?

Prob. 9-124:

Repeat Prob. 9-123 for the case of three stages of compression with intercooling and three stages with expansion with reheating.

Prob. 9-123:

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kPa and 17°C. This system uses a regenerator as well as reheating and intercooling. The pressure ratio across each compressor is 4; 300 kJ/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°C. Determine this system's thermal efficiency. Assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature.