A simplified method for heat transfer prediction of supercritical fluids in circular tubes

This paper presents a new method for heat transfer prediction in supercritical fluids. Emphasis is put on the simplicity of the correlation structure, its explicit coupling with physical phenomena and the selection criteria of the test data. Assessment of qualitative behaviour of heat transfer is carried out based on existing test data and the experience gathered in the open literature. A single dimensionless number, the acceleration number, is introduced to correct the deviation of heat transfer of supercritical fluids from that of conventional fluids. The new correlation structure excludes any direct dependence of the heat transfer coefficient on the wall surface temperature, and eliminates possible numerical instability. The uncertainty analysis of the test data provides information about the sources and the levels of uncertainties of various parameters, and is strongly required for the selection of both the dimensionless parameters implemented into the heat transfer correlation and the test data for the derivation of correlations. Detailed assessment shows that the new correlation gives reasonable prediction accuracy over a wide parameter range and is also capable of predicting heat transfer behaviour in the heat transfer deterioration region. (C) 2009 Elsevier Ltd. All rights reserved.