NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Evaporation and Condensation Heat Transfer Performance of Flammable Refrigerants in Brazed Plate Heat Exchangers
Published
Author(s)
Mark A. Kedzierski, J C. Chato, T J. Rabas
Abstract
Measured overall Nusselt numbers were determined for R22, R290, R290/600a, and R32/152a undergoing evaporation and condensation in a brazed plate heat exchanger. The refrigerants experienced wavy, stratified flow at low heat and mass fluxes, 1.3 to 8.3 kW/m2 and 1.6 to 19 kg/m2 s, respectively. Heat transfer correlations from the literature for in-tube and channel flow of refrigerants with similar heat and mass fluxes were compared to the measured Nusselt numbers and found unsatisfactory. Evaporation and condensation correlations were developed from the data for this study for the combined data of R22, R290, and R290/600a and the data for R32/152a. Separate correlations were needed because the lubricant used for R32/152a is different than the lubricant used for the other refrigerants.
Kedzierski, M.
, Chato, J.
and Rabas, T.
(2000),
Evaporation and Condensation Heat Transfer Performance of Flammable Refrigerants in Brazed Plate Heat Exchangers, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD
(Accessed October 10, 2025)