Consider the following air-conditioning system design which involves a refrigeration process ('cooling coil unit') and a mixing process ('mixing box'). Cooling Unit 2 Mixing Box mai T, Ø1 w2 T2 Ø2 |Mcoolant Tcoolant,in 3 maz T3 03 Condensate Cooling Coil Coolant Return Air For steady state operation of the cooling coil unit at 1 atm, determine the following: 42. the mass balance for the dry air; a) mai < ma2 b) ma1 = ma2 = ma c) ma1 - maz = Ma d) mai > ma2 %3D 43. the mass balance for the water; a) my1 = my2 – MH20 b) my1 = my2 = MH20 c) my1 + mv2 = MH20 d) my1 = my2 + mµ20 44. the energy rate balance; a) Qcooling = ma[(ha1 + w,hg1) – (haz + wzhg2) – mu20hu20o] b) Čcooling = m,[(ha1 + w,hg1) + (ha2 + wzhg2)] – mu20hu20 c) Čcooling = Mal(ha1 + w,hgs) – (haz + wzhgz)] – mH20hH20 d) Čcooling = mal(hai + wihg1) – (haz + wzhg2)] – (@1 – wz)hrz %3D

Consider the following air-conditioning system design which involves a refrigeration process ('cooling coil unit') and a mixing process ('mixing box'). Cooling Unit 2 Mixing Box mai T, Ø1 w2 T2 Ø2 |Mcoolant Tcoolant,in 3 maz T3 03 Condensate Cooling Coil Coolant Return Air For steady state operation of the cooling coil unit at 1 atm, determine the following: 42. the mass balance for the dry air; a) mai < ma2 b) ma1 = ma2 = ma c) ma1 - maz = Ma d) mai > ma2 %3D 43. the mass balance for the water; a) my1 = my2 – MH20 b) my1 = my2 = MH20 c) my1 + mv2 = MH20 d) my1 = my2 + mµ20 44. the energy rate balance; a) Qcooling = ma[(ha1 + w,hg1) – (haz + wzhg2) – mu20hu20o] b) Čcooling = m,[(ha1 + w,hg1) + (ha2 + wzhg2)] – mu20hu20 c) Čcooling = Mal(ha1 + w,hgs) – (haz + wzhgz)] – mH20hH20 d) Čcooling = mal(hai + wihg1) – (haz + wzhg2)] – (@1 – wz)hrz %3D

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.2DP

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