Heat Pump Experiments with Nonazeotropic Mixtures Preporatory Work

• The interest of nonazeotropic mixtures as working fluids in heat pumps has increasedin the last years. This is due to the harmfulness of CFC fluids for the ozone layer and thatnonazeotropic mixtures have been found as an alternative to the use of CFCs.A project has been started consisting of making an experimental study of an onefamily-house heat pump working with nonazeotropic mixtures of HCFC22 and HCFCI42b.The first part of the project is to instrument the heat pump and to make the measuringequipment work properly before starting further experiments. This includes three steps in thedevelopment of the work. Calibration of the measuring equipment (thermocouples, pressuretransducers, flowmeter), writing of a measuring program check that all instrumentation isdone in a correct way and works well.Test runs of the heat pump have been done with HCFC22 as refrigerant in order tocheck the measuring equipment. The results showed a misfit of the heat balance and afterverifications, it occurred that the problem was due to an incorrectly placed thermocouple.Since the misfit was too high to be only due to heat losses, more tests run have beenundertaken to find the sources of errors. In order to get accurate results, the valve on theradiator water side should be changed, a new temperature regulator of the brine should beinstalled and the condenser should be isolated.The first part is completed and before starting the experiments with nonazeotropicmixtures, some work is still required. The electronic expansion valve should be placed in thesystem and a regulating program to control it should be written.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering (hsv//eng)

Keyword

HCFC22

Heat pump application

nonazeotropic mixtures

CFC12

Publication and Content Type

rap (subject category)

vet (subject category)