Question

Explain which of the Laws of Thermodynamics are adhered to, or not, for the powerplant illustrated in Figure Q4 4. (a) BOILER Resistance beuter Figure Q4 TURHINE GIENERATO PUMP CONDENSER Two perfectly insulated, rigid wall tanks are connected by a pipe containing a valve (b) Tank A contains 3 kg of air at 75°C and 0.5 bar Tank B holds 9 kg of air at 25 C and 1.5bar The valve is opened and the air is allowed to mix. Assuming reversibility and no heat transfer to or from the surroundings, determine the final equilibrium temperature and pressure of the air in the tanks. 4.5 kg/s of air enters a high pressure centrifugal compressor at a stagnation temperature of 450 K where it is compressed through a pressure ratio of 7:1 with an isentropic efficiency of 90% (c) () Determine the stagnation temperature of the air leaving the compressor (i) Determine the power required to drive this compressor The relationship between P and T for an isentropic compression may be taken as: 02 r To1 01

Answer 1

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(5.993十5232 ) Tol 450 K Ср: 1.oos KJ /kg. K Poa isemtaopic Poocess Y. 4. т.semtoopic efA ciercy o.84.64- 45o Пог- 450 Тог 821,82 K . P - 4.Sx 1.005 (821.82- 4 So)