Developing Two-Phase R134a Flow after an Expansion Valve in an 8.7mm Tube
نویسندگان
چکیده
Two-phase flow distribution in evaporators has been shown to be directly affected by the development of the flow between the expansion device and the heat exchanger, namely, the separation characteristics of the two phases. For this reason the development of adiabatic two-phase R134a in an 8.7mm transparent PVC tube directly after an expansion valve was studied. This paper presents a mapping of this developing adiabatic two-phase R134a flow until the flow is “fully developed”. This mapping was obtained through the use of a high speed video camera traversing a 700mm long tube and recording the various flow regimes seen by the fluid.
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