) A diffuser takes in 2.5 kg s−1 of air at 52 ◦C and 12 bar through an inlet of 4 cm. It discharges through an outlet of 12 cm diameter at 10 bar and 152 ◦C. The diffuser is heated. Determine inlet and outlet velocities, the change in enthalpy that occurs, and the heat gain. Assume air is an ideal gas. [155 m s−1 , 27.0 m s−1 , −11.5 kJ kg−1 ]

Abrayton cycle operates with a regenerator on the air-standard with properties evaluated at 400 k. the tem- perature of the air entering the compressor is 350k while the temperature of the air exiting the compressor is 600 k. the temperature of the air entering the turbine is 1600 k. the overall cycle produced 600 kj/kg of net work out. assuming a regenerator effectiveness of 0.8, what is the temperature of the air before heat addition (combustion)? draw this process on a t - s diagram