# A 22 kw refrigerator or heat pump operates between 17

• No School
• AA 1
• 144
• 100% (8) 8 out of 8 people found this document helpful

Course Hero uses AI to attempt to automatically extract content from documents to surface to you and others so you can study better, e.g., in search results, to enrich docs, and more. This preview shows page 83 - 85 out of 144 pages.

A 2.2 kW refrigerator or heat pump operates between – 17oC and 38oC. Determine the maximum theoretical heat that can be transferred from thecold reservoir.a) 10.24 kWb) 12.44 kWc) 14.01 kWd) 14.24 kWSolution:LHLLTTTWQ=()kW24.101738172732.2TTTWQLHHH=+==2.Determine the final volume of the isentropic compression of 1 m3air from 20 kPaa to a pressure of 100 kPaa.a) 1.9047 m3b) 0.5253 m3c) 0.3168 m3d) 0.1061 m3Solution:()34.113k12112m3168.010020m1ppVV===3.What is the clearance of an ideal Otto engine if the efficiency is 40 % and k = 1.3?a) 21.18 %b) 12.27 %c) 22.28 %d) 23.28 %Solution:489.540.011e11r3.011k1k===()()%28.22%1001489.51%1001r1ck===4.A 500 Hp internal combustion engine has a brake mean effective pressure of 551.5 kPa at full load. What is the friction power if the mechanicalefficiency is 85 %?a) 75 Hpb) 88.24 Hpc) 78.24 Hpd) 98.24 HpSolution:Hp24.8850085.0500BPBPBPIPFPm==η==5.A fiber glass insulating board with thermal conductivity of 0.05 W/m-oC is to be used to limit the heat losses to 100 W/m2for a temperaturedifference of 150oC across the board. Determine the thickness of the insulating board.a) 57 mmb) 65 mmc) 56 mmd) 75 mmSolution:()()()mm75m075.0m/W100C150Cm/W05.0AqTkx2ook====6.A Brayton cycle has a compression ratio of 11. Find the cycle thermal efficiency if the compression and expansion exponent is 1.25.a) 62.99%b) 45.09 %c) 49.05 %d) 69.22 %Solution:()()()()()()%09.45%1001111%100r11%100r11e25.01nkk1npthe====7.An air standard Otto cycle has a compression ratio of 10. The initial temperature is 30oC and initial pressure is 100 kPaa. If heat added is 1150kJ/kg, find the mean effective pressure.a) 884.3 kPab) 848.3 kPac) 488.3 kPad) 838.4 kPaProducer of Brilliant Mechanical Engineers in the CALABARZONEngineering Review Center# 2 Alvaran’s Apartment, Purok 7, Halang City of Calamba, LagunaTel/Fax # (049) 545 9828Cell # 0917 545 6548
JCSF Engineering Review CenterIPD PPD General Examination2Solution:()()()()%2.60%1001011%100r11e4.01kkth===()()()kg/kJ3.6921501602.0qewAth===()()kg/m8699.01002733028708.0pRTv31=+==kg/m08699.0108699.0rvv3k12===kPa3.88408699.08699.03.692vvwvwp21Dm====8.A heater has an average temperature of coil is 80oC. Air enters at 29oC and leaves at 65oC. Find the by-pass factor.a) 0.50b) 0.3191c) 0.2941d) 0.7059Solution:2941.029806580BPF==9.For an electric generator running at 15 revolution per second and 60 Hz, find the number of poles.a) 16 polesb) 10 polesc) 12 polesd) 8 polesSolution:()()poles8601560120Nf120p===10.A feed having 18 % moisture delivers 9000 kg/hr of dried product having 97 % solid. Find the moisture removed.a) 1646.34 kg/hrb) 1466.34 kg/hrc) 1664.34 kg/hrd) 1436.46 kg/hrSolution:()()2211MC1mMC1m=()()hr/kg34.6461018.0103.019000MC1MC1mm1221===hr/kg34.16460009334.64610mmm21===11.A thermal power plant generates 9000 kW and has also 400 kW power needed for auxiliaries. If heat generated by fuel is 15500 kW, what is the netthermal efficiency in%?

Course Hero member to access this document

Course Hero member to access this document

End of preview. Want to read all 144 pages?

Course Hero member to access this document

Term
Fall
Professor
NoProfessor
Tags
JCSF Engineering Review Center