Question

An inventor claims that she/he created a new device generating electricity. The device uses air as a working fluid. As a patent lawyer, you want to know the efficiency of the cycle. The cycle starts with heat transfer in at constant volume. The initial temperature is Ty and the temperature at the end of heat transfer is T2. Then, the air expands until the temperature reaches to T1. Heat transfer out occurs at a constant temperature. Plot this cycle on T-s and P-v diagrams. Express the cycle efficiency as only a function of T1 and T2. Apply cold-standard analysis.

Answer 1

Aas The P-V and T- S plot is given below Expansion Heat out Heat in Nothing is so assuning mentioned about the process of expansion, expansion takes place at a constant preu Now Wcycle= Area of Cycle ei p. V plot 1.3 Pz (Vg-V) - Wiso (tu) = P2CV3-vi) - Pivila Na * = PzCV3-VD) - Pivi lo pa (Riu = co(T2-T1) Qout = Wiso = PIN lun. - Pivila la . T2/vx = Pivila Pa = RT Pi TIVT = RTilu T2

CQ in Chout Rin CV (T2-TI) - RT, In I2 Сх (1-1) n = '- RTI IM IZ Cv (T2-T1) Also, cu- & = 1- (-1) Tilm Iz n = 1- kr1 lu7 2 k (T2-T1) 12-11