For each of the cases below determine if the heat engine sat

For each of the cases below determine if the heat engine satisfies the first law (energy equation) and if in violates the second law. Q_H = 6 KW. Q_L = KW. W = 2 KW Q_H = 6 KW. Q_L = 0KW. W= 6 KW Q_H = 6 KW. Q_L = 2 KW. W = 5 KW Q_H = 6 KW. Q_L = 6 KW. W = 0 KW

Solution

a)Here, U is the internal energy:

U = (Q_H-Q_L)+W = 4KW

b) U=12 KW

c) U=8 KW

d) U=0 KW

According to the First Law of Thermodynamics, the change dU in the internal energy of the sub-system is the sum of the heat q added to the sub-system, less any work w done by the sub-system.

The change in the subsystem\'s exergy plus the useful work done by the subsystem (or, the change in the subsystem\'s exergy less any work, additional to that done by the pressure reservoir, done on the system) must be less than or equal to zero.