Investigation on Fluid-Structure Thermal Interaction Related to Eddy Structure on Branch Jet in T-Junction

Water experiment and numerical simulation under thermal interaction conditions between fluid and structure were conducted for a T-junction piping system (T-pipe) consisting of a rectangular duct for main stream and a circular pipe for branch stream. In the experiment, flow patterns were changed from the deflecting jet case in which branch flow went above the wall surface to the wall jet case in which branch flow went on the wall surface. Temperatures at 2mm from the wall in fluid, on the wall and at 3mm inside from the wall in structure along a vertical trace line were measured simultaneously. Numerical results indicated that the fluid temperature distribution near the wall was much affected by the thermal interaction with the structure and that fluid-structure thermal interaction was necessarily considered for thermal fatigue estimation in the thermal striping phenomena.