关键词: 燃气涡轮机;冷却叶片;对流传热;旋转

Abstract: A two-equation turbulence model with additional term for Coriolis and buoyancy was used to study turbulent flow and heat transfer in a rotating ribbed serpentine passage. Using air as the coolant, operating conditions were selected to match the test model operating parameters. The simulation results are almost consistent with the experimental data. The results indicated that the unbalance distribution of Coroilis force plays an important role in flow and heat transfer in rotational passage. Two new flow structures caused by Coroilis force were found: (1) Axial velocity profile is outward along Coroilis force direction; (2) Secondary flow appears on the section perpendicular to the main flow. These two phenomena enforce the heat transfer on the face the Coroilis force point to and both the side faces. The heat transfer on opposite face is weakened at lower rotating speed and recovers with the rotating arisen. Coroilis force increases pressure loss in the ribbed passage while centrifugal buoyancy force decreases pressure loss.

Key words: Gas turbine;Cooled blade;Convective heat transfer;Gyration