Share

IIR document

Reasons for drop in shell-and-tube condenser performance when replacing R22 with zeotropic mixtures. 2. Investigation of mass transfer resistance effects.

Author(s) : KARLSSON T., VAMLING L.

Type of article: Article, IJR article

Summary

Detailed calculations of condensation outside a column of horizontal smooth tubes have been carried out in order to investigate the influence of mass transfer resistance for a zeotropic refrigerant mixture. Diffusive transport is calculated locally in both phases. Calculation results show that mass transfer resistance in the gas phase reduces heat transfer by 10-20% for a binary mixture with a glide similar to that of R407C. The decrease in heat transfer due to poor mixing in the condensate is from 15 to 65% for the conditions investigated; the lower the duty, the greater the decrease. Results show that if assuming mixing in the condensate by diffusion only, the degrees of mixing and the duty dependency are similar to results in earlier work where calculations were matched to experimental data. Diffusion is likely to be the dominant mixing mechanism in the condensate, and the mixing is poor under certain conditions, which might explain the drop in condenser performance for some heat pump applications.

Available documents

Format PDF

Pages: 561-566

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: Reasons for drop in shell-and-tube condenser performance when replacing R22 with zeotropic mixtures. 2. Investigation of mass transfer resistance effects.
  • Record ID : 2004-2792
  • Languages: English
  • Source: International Journal of Refrigeration - Revue Internationale du Froid - vol. 27 - n. 5
  • Publication date: 2004/08

Links


See other articles in this issue (11)
See the source

Indexing