Summary on the Results of Two Computational Fluid Dynamic Benchmarks of Tube and Different Channel Geometries

Two computational uid dynamic (CFD) benchmarks have been performed to assess the\udprediction accuracy and sensitivity of CFD codes for heat transfer in different geome-\udtries. The rst benchmark focused on heat transfer to water in a tube (rst benchmark),\udwhile the second benchmark covered heat transfer to water in two different channel geo-\udmetries (second benchmark) at supercritical pressures. In the rst round with the experi-\udmental data unknown to the participants (i.e., blind calculations), CFD calculations were\udconducted with initial boundary conditions and simpler CFD models. After assessment\udagainst measurements, the calculations were repeated with the rened boundary condi-\udtions and material properties in the follow-up calculation phase. Overall, the CFD codes\udseem to be able to capture the general trend of heat transfer in the tube and the annular\udchannel but further improvements are required in order to enhance the prediction accu-\udracy. Finally, sensitivity analyses on the numerical mesh and the boundary conditions\udwere performed. It was found that the prediction accuracy has not been improved with\udthe introduction of ner meshes and the effect of mass ux on the result is the strongest\udamong various investigated boundary conditions