Share

IIR document

Capillary tube selection for HCFC-22 alternatives.

Author(s) : JUNG D., PARK C., PARK B.

Type of article: Article, IJR article

Summary

In the paper, pressure drop through a capillary tube is modelled in an attempt to predict the size of capillary tubes used in residential air conditioners and also to provide simple correlating equations for practicing engineers. Stoecker's basic model was modified with the consideration of various effects due to subcooling, area contraction, different equations for viscosity and friction factor, and finally mixture effect. McAdam's equation for the two-phase viscosity and Stoecker's equation for the friction factor yielded the best results among various equations. With these equations, the modified model yielded the performance data that are comparable to those in the ASHRAE handbook. After the model was validated with experimental data for CFC-12, HFC-134a, HCFC-22, and R407C, performance data were generated for HCFC-22 and its alternatives, HFC-134a, R407C and R410A under the following conditions: condensing temperature; 40, 45, 50, 55 °C, subcooling: 0, 2.5, 5 °C, capillary tube diameter; 1.2-2.4 mm, mass flow rate; 5-50 g/s. These data showed that the capillary tube length varies uniformly with the changes in condensing temperature and subcooling. Finally, a regression analysis was performed to determine the dependence of mass flow rate on the length and diameter of a capillary tube, condensing temperature, and subcooling. Thus determined simple practical equations yielded a mean deviation of 2.4% for 1488 data obtained for two pure and two mixed refrigerants examined in this study.

Available documents

Format PDF

Pages: 604-614

Available

  • Public price

    20 €

  • Member price*

    Free

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Capillary tube selection for HCFC-22 alternatives.
  • Record ID : 2000-0949
  • Languages: English
  • Source: International Journal of Refrigeration - Revue Internationale du Froid - vol. 22 - n. 8
  • Publication date: 1999/12

Links


See other articles in this issue (5)
See the source

Indexing