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The paper presents a combined experimental and numerical program directed at improving the accuracy of conjugate heat transfer CFD simulations of engine water cooling jackets. As a first step in the process, a comparison between experimental measurements from a test facility at Villanova University and CFD numerical predictions by at the University of Modena is reported. The experimental test section consists of a horizontal aluminium channel heated electrically and supplied with a constant volumetric flow rate. The operating fluid is a binary 50/50 mixture by volume of ethylene-glycol and water, in order to reproduce a situation as close as possible to actual engine cooling system operations. Temperatures are measured along the channel at several axial locations. On the CFD side, an extensive program reproducing the experiments is carried out in order to assess the predictive capabilities of some of the most commonly used eddy viscosity models available in literature.

An experimental program has been conducted to evaluate the thermal performance, the relationship between surface heat flux and surface temperature, of two engine coolants at off-design operating conditions. These conditions could be caused by high ambient temperature or a faulty system seal. The experimental data shows that system pressure has the most pronounced effect on thermal performance. Lowering the system pressure enhances boiling by reducing the saturation temperature. Using a revised Chen correlation, analytical predictions have been obtained which agree with the experimental results

Test results have been obtained on the thermal performance of aqueous mixtures of propylene-glycol and ethylene-glycol for conditions simulating automotive engine operation. For the present study, thermal performance is defined as the test section surface temperature for a given set of operating conditions. In addition to testing over a wide range of surface heat fluxes up to 2.3 MW/m2, data were also obtained at different mixture concentrations. For all cases considered, both coolant mixtures provided similar results.