Question

For same heat input and work done/required, arrange the above cycle in decreasing order of efficiency with your justification.

Carnot cycle, Duel cycle, Carnot refrigeration cycle, Rankine cycle, Vapor compression cycle and Brayton cycle in your own words

Answer 1

We had efficiencies for the " Carnot cycle, Duel cycle, Rankine cycle and Brayton cycle", and coefficient of performances for the Carnot refrigeration cycle and Vapor Compression cycle. So the decreasing order of the efficiencies are as follows,

Carnot cycle > Duel cycle > Brayton cycle > Rankine cycle

The decreasing order of the coefficient of performances is as follows,

Carnot refrigeration cycle > Vapor compression cycle

As we observe in the Carnot cycle there are completely reversible processes and heat addition and rejection takes place at a constant temperature. So this has the highest efficiency in all the processes. Duel cycle is more relevant after Carnot to increase the level of reversibility after its ranking and Brayton is the most efficient than the ranking cycle since ranking cycle loses more energy than the brayton cycle.