Study on the Flow Characteristics of R-22, R-l34a in Small Diameter Tubes

R-22 및 R-134a의 세관 내 유동 특성에 관한 연구

  • Published : 2002.09.01

Abstract

Experimental work was performed on the flow characteristics of R-22 and R-l34a in small diameter tubes. The experimental apparatus was made up of liquid pump, pre-heater, sight-glass, condenser and measurement instruments. The sight-glass for flow pattern observations was located at the outlet of the pre-heater. The experiment was carried out to show the flow characteristics of R-22 and R-l34a. Data were taken with test conditions in the following ranges; the mass flux was ranged from 100 to 1,000 kg/$m^2s$, the saturation temperature was $30^{\circ}C$ and the vapor quality was ranged from 0.1 to 0.9. The main results were summarized as follows; In the flow patterns during evaporation, the annular flow in a 2 mm inner diameter tube occurred at a relatively lower quality and mass velocity, compared to the flow in a 8mm inner diameter tube. The evaporation flow in small diameter tubes has been shown major deviations with the Mandhane, Taitel-Dukler's and Wambs-ganss' flow pattern maps but it was similar to the Dobson's flow pattern map.

Keywords

References

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