Synthesis of a CFD benchmarking exercise for a T-junction with wall

The validation exercise has shown that LES shows the best agreement with the experimental data followed by hybrid (LES/RANS), URANS and RANS models, respectively. The velocity and the thermal fields in the fluid region are correctly predicted by the proper use of the LES modelling. Whereas, the accurate prediction of the thermal field in the solid requires very long sampling time to achieve statistically converged solution, which of course requires an enormous computational power. Therefore, the statistical convergence of the thermal field in the solid has been found to be one bottleneck in order to accurately predict the temperature fluctuations in the wall and the transient heat transfer. However, measuring the small amplitude temperature fluctuations is also associated with an uncertainty so the disagreement between CFD and measurements (of the order of 10%) can also be attributed, in part, to uncertainties in the measurements.