Experimental Study of Short-Tube Refrigerant Flow.

摘要

Short tubes are being used for refrigerant expansion devices for their durability, ease of application, and low cost. Unlike capillary tubes, the design data for short tubes are extremely rare, and yet it is widely recognized that sharp-edge orifice formula will not be adequate to predict short tube fluid flow. Correlations to size the short-tubes for air-conditioning units and heat pumps are definitely needed. Five short tubes with length-to-diameter ratios ranging from 7.5 to 11.9 were tested on a heat pump system with R-22 as the fluid. Correlations to calculate the short-tube opening size and length were formed from the test results. The correlations were used on a set of data from tests performed by other researchers. The maximum deviation of calculated short tube openings and length from measured values were 6.7% and 18%, with average deviation at 3% and 4.1%, respectively. 9 refs., 8 figs., 1 tab. (ERA citation 14:000781)