Transfert thermique en condensation dans les échangeurs à plaques et ailettes

The purpose of this report is to list and provide a critical review of the heat transfer coefficient calculation methods within plate-fin heat exchangers (PFHE), and more specifically in the two-phase condensing flow case.

This document is exclusively available to GRETh members who have requested a report on this topic at the 2021 General Assembly.

In general, this report, after an important screening of the scientific publications databases, lists the heat transfer coefficient calculation methods in the form of correlations, which allows a simplified use.

The most relevant correlations have been selected according to the following main criteria :

• the choice of correlations specifically developed or applied to PFHE & correlations widely accepted in the scientific literature in horizontal mini-channels;
• the implementation of correlations as close as possible to their validity range & outside their validity range (reliability & robustness correlation analysis).

The content of this report is focused according to :

• Comparisons of the selected correlations with correlations considered "more conservative" and to be applicable to the same operating conditions in order to judge the quality of the obtained results;
• As far as possible, comparisons outside the validity domains for which the PFHE specific correlations were developed in order to assess the relevance of these correlations.

Thus, the results presented in this report, mainly in the form of heat transfer coefficient evolution graphs, are the outcome of the new correlations coding and calculation (as well as the usual correlations) in specific operation and variation cases.

We hope that this report will bring you concrete elements that can be integrated for your heat exchanger sizing and/or simulation of whole systems.