Heat transfer and pressure drop model of in-tube condensation in a vapor-compression system

Jiange Xiao, Pega Hrnjak

Research output: Chapter in Book/Report/Conference proceedingConference contribution


A typical “3-zone” models assume uniform temperature in the cross section of the tube during condensation. The first droplet occurs when the bulk quality is 1. However, as soon as wall temperature drops to the saturation, condensation begins regardless of what the bulk temperature is. The new heat transfer and pressure drop models use “5-zone” approach, seeking to capture the two-phase mechanisms in the condensing superheated (CSH) and condensing subcooled (CSC) regions. Heat transfer coefficient and pressure drop measured in 4 and 6 mm tubes are used to validate the new approach in the range: mass flux from 50 to 400 kg m-2 s-1; heat flux 5 to 15 kW m-2; condensing temperatures 30 and 50oC. The refrigerants explored are R744, R32, R410A, R134a, and R1233zd(E). The new models are more physical and better fit the experimental data than the conventional models, especially in the CSH region. This is because the latent heat and vapor-liquid interaction are present even though the bulk temperature indicates otherwise.

Original languageEnglish (US)
Title of host publicationICR 2019 - 25th IIR International Congress of Refrigeration
EditorsVasile Minea
PublisherInternational Institute of Refrigeration
Number of pages9
ISBN (Electronic)9782362150357
StatePublished - 2019
Event25th IIR International Congress of Refrigeration, ICR 2019 - Montreal, Canada
Duration: Aug 24 2019Aug 30 2019

Publication series

NameRefrigeration Science and Technology
ISSN (Print)0151-1637


Conference25th IIR International Congress of Refrigeration, ICR 2019


  • Condensing superheated region
  • Heat transfer
  • Non-equilibrium
  • Pressure drop
  • Vapor-compression system

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Electrical and Electronic Engineering
  • Mechanical Engineering
  • Condensed Matter Physics


Dive into the research topics of 'Heat transfer and pressure drop model of in-tube condensation in a vapor-compression system'. Together they form a unique fingerprint.

Cite this