| Title |
Study on the Flow Characteristics of R-22, R-134a in Small Diameter Tubes |
| Authors |
홍진우 ; 정재천 ; 장승환 ; 권옥배 ; 오후규 |
| Keywords |
Flow pattern ; 유동 양식 ; Small diameter tube ; 세관 ; R-22, R-134a |
| Abstract |
Experimental work was performed on the flow characteristics of R-22 and R-134a 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-134a. Data were taken with test conditions in the following ranges; the mass flux was ranged from 100 to 1,000kg/m2s, the saturation temperature was 30℃ 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 2mm 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 Wambsganss' flow pattern maps but it was similar to the Dobson's flow pattern map. |