18 May 2017

O.4.2.3 Experimental Comparison of Different Two-Phase Refrigerant Distribution Devices

For larger air-source heat pumps, especially when trying to minimize the inner volume and the refrigerant content in the evaporator, refrigerant distribution to a high amount of parallel passes through the evaporator is a challenge. As the refrigerant leaves the expansion valve partly evaporated, this 2-phase refrigerant has to be distributed to the passes of the evaporator in a way that ideally all passes get the same amount of liquid.
In the frame of the EU-founded project “GreenHeatPump” a novel distributor concept was developed and included in a prototype Heat Pump. This novel distributor and several conventional distributors have been subject to extensive tests on a dedicated test rig.
In this paper the test rig is explained in detail and the results for the different distributors are presented.