Question

Thermodynamics 2: STARTING FROM QS 2)

1) In an ideal Brayton cycle air enters the compressor at T = 300K and P = 1 bar with a volumetric flow rate = 20 m3/s. Air enters the turbine at P = 10 bar and T = 1800K.

Find:
a) The thermal efficiency
b) The backwork ratio
c) The net power generation in MW

2) For the same states above consider a cycle where the isentropic efficiency of the compressor and turbine are both 90%. Find the efficiency and backwork ratio for this cycle.
3) For the ideal cycle, add a regenerator with an effectiveness of 75%. Find the thermal efficiency for this cycle.
4) Determine the exergy in the heat rejected from the ideal cycle with no regeneration.
5) Design a Rankine cycle to utilize the heat rejected from the ideal Brayton cycle. Find the thermal efficiency of the Rankine cycle and of the combined cycle.
6) What is the exergetic efficiency of your Rankine cycle?

Answer 1