Numerical investigation of flow field and heat transfer characteristics in a latticework duct with jet cooling structures

摘要

Interaction effects of the latticework duct and jet cooling structures on the flow structure and heat transfer were numerically investigated. The latticework duct included eleven sub-channels both on the top wall and bottom wall. The crossing angle was set as 90 degrees. The jet cooling structures had a curved target surface and seven jet nozzles. The jet cooling structures and latticework duct were connected by three different jet nozzle locations and two different jet nozzle shapes, respectively. In addition, six different mass flow ratios in the jet cooling structures were considered. Results showed that the flow field and heat transfer characteristics were sensitive to the jet nozzle location, shapes and mass flow ratios. When the mass flow ratio was increased in the jet cooling structure, the heat transfer was augmented in the jet cooling structure while it was decreased in the latticework duct. Using the jet nozzle near the turning region, the upward spiral flow and helical flow in the sub-channel of the latticework became weak, corresponding to a low Nusselt number in the latticework duct. However, the heat transfer in the jet cooling structure was enhanced. Furthermore, the circular jet nozzle provided high friction factor and Nusselt number both for the jet cooling structures and latticework duct.