多腔室凹槽对涡轮叶顶流动传热特性影响的数值研究

In order to reduce the heat load and leakage flow rate in the turbine blade tip，the present research focus on the first stage turbine blade of GE-E³，applies the rib structure to the blade tip. Three-dimensional Reynolds-Averaged Navier-Stokes（RANS）and standard k-ω turbulent model were utilized in all the present computations. The effects of multi-cavity tip on the blade tip leakage flow and heat transfer characteristic were numerically investigated. The numerical results show that as the number of ribs increases，the heat-transfer coefficients reduce on the blade tips composed of smaller tip cavities. Compared with the flat blade tip，the heat transfer coefficient of the multi-cavity tips with the grid structure is remarkably reduced. The scraping vortex in the cavity can effectively decrease the leakage flow. The mass flow rate of the leakage flow decreases to varying degrees for different multi-cavity tips. An aero-labyrinth liked sealing effect is formed by the grid structure，which has obvious leakage flow control effect in 0～20% stream-wise region.