A detailed programme of work has been undertaken to quantify the suitability of predictive methods for accurate determination of the levels of boiling heat transfer within an internal combustion (IC) engine cooling gallery simulator. An extensive array of experimental data has been obtained as the basis for the predictive validation. Working on the principle of superposition, the convective component of heat transfer has been represented by the established Dittus-Boelter correlation which has been extensively modified to account for developing boundary layers, surface roughness and nearwall viscous effects. The boiling component has been represented by the Chen model, modified for binary fluids and subcooling. For the IC engine cooling application it is concluded that the application of the Chen approach must be complemented by a convective heat transfer model that accurately represents the complex thermo-fluid situation being experienced within a developing flow.

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A study has been undertaken to assess the capability of incorporating different empirical approaches in a computational ftuid dynamics (CFD) environment for predicting boiling heat transfer. The application is for internal combustion (IC) engine cooling galleries and experimental validation work has been undertaken. Three different boiling heat transfer models are described, one based on the principle of superposition (Chen) and two based on the partial boiling method (Thom and Cipolla). Overall, the Thom partial boiling approach was found to be the most representative of the three considered. However, numerous issues were found to be evident whatever approach was adopted and these are discussed in the paper. The partial boiling model was found to be the most simple to incorporate in the CFD model.

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