Objective

Address your concerns/suggestionsReview

Learn about Cooling Systems Compressor cooling circlesSorption coilingEvaporative cooling

Vapor Compression CycleExpansion valveOutdoor 105FIndoor 75F

Thermodynamics - review

Thermodynamics - review

Thermodynamics - reviewEnthalpy: h [J/kg, Btu/lb]Temperature change T

h = cp T only for the same phase (air, water)

What if we have change of the phase -evaporation or condensation?

Entropy: s [J/kgK, Btu/lbF] h = T s for evaporation or condensation

What is the COP?Congressional Observer Publications California Offset Printers, IncCoefficient of PerformanceSlang for a policeman

COPCoefficient of Performance

Refrigeration Cycle

Components of a DX systemCompressorEvaporatorCondenserExpansion valve

92 F56 F69 psigDB = 77 FWB = 64 Forificecapillary tubeTXV110 F~200 psigDB = 60 FWB = 53 FHigh pressure, high boiling/condensing point Low pressure, low boiling pointDX Cooling Machine

Air Cooled ChillerOutside air 95FInside 75FWater 42FBuildingWater 52FChiller

Water Cooled ChillerOutside air 95FInside 75FWater 42FBuildingWater 52FWater 120FWater 100FCooling towerChiller

CoolingEvaporative cooling Compressor CoolingSorption cooling DX machine Chiller Air Cooled Condenser Water Cooled CondenserConvert Cooling machine (DX machine) to heat pumps Evaporative Chiller

Air cooled condenserOnly for small capacityCool the water or directly the refrigerant for compressor chillers

Cooling towerProvide cooling water for condenser or absorption

TypeLocation Legionella

Evaporative CoolingWet media/water spray directRaise absolute humidity, lowers temperature of conditioned airCooling tower indirectCools through a heat exchangerLowers temperature, does not affect absolute humidityCan directly cool air in cold weather

Evaporative Cooling

What is Heat Pump ?CoolingHeatingOutside 95FOutside 55F Inside 75FInside 75F

www.srpnet.com/energy/pumpworks.aspx Compressor

2) Condenser

3) Evaporator

4) Air handler

5) Reversing valve and expansion valve

COP for heat pump

Energy Storage Systems

Daily distribution of cooling load

Thermal StorageMake ice/chilled water at times of low demand or low energy pricesStore water in insulated containerCan be used to reduce overall demandWater can be used as secondary water source for fire protectionIce/snow

Thermal Storage

Reading Assignment

Tao and Janis Chapter 4