Predicting Boiling Heat Transfer in IC Engine Cooling Jackets with ANSYS Fluent
There has been a change in the thermal management of IC engines where engineers now like to harness the superior cooling rates available when limited and controlled Nucleate Boiling is used to remove heat from high temperature zones. Any flaws in the design of such systems, such as uncontrolled heat transfer that leads to Film Boiling (Dry out condition), can have an adverse effect on the cooling performance. A detailed boiling heat transfer model for this design process would allow engineers not only to weed out flawed coolant passages early, but also to accurately predict the temperature for subsequent analysis like thermal stress analysis in solid, IC engine combustion analysis etc. In this seminar, a CFD model for boiling heat transfer will be presented. This model is developed using Mixture Multiphase framework. 1-D correlations for boiling heat transfer at the wall are adapted for 3D CFD environment and validated against experimental results. The working fluid is 50% aqueous-ethylene-glycol, typical antifreeze mixture used in IC engine cooling. For mass transfer inside the engine jacket Evaporation–Condensation model is used, which is a built-in model in ANSYS Fluent. The results obtained from a typical IC engine water jacket geometry will be discussed.