以经典PW-E3跨音速涡轮叶片为研究对象，围绕高负荷跨音速涡轮叶尖区域,通过求解三维Reynolds-Averaged Navier-Stokes（RANS）方程和SST湍流模型,系统分析了不同叶尖间隙下的气动与换热特性及其影响机制，揭示了叶尖区域复杂流动结构、激波及膨胀波的形成、分布与演化规律。结果表明，叶尖区域亚音速-超音速的转换显著影响局部压力、速度和换热分布，膨胀波和激波的相互作用导致壁面出现高低不均的换热带。叶尖间隙高度增大使超音速区范围扩大，激波与分离泡结构增强，换热系数面平均值相应升高，叶尖间隙由0.23增加至1.38时，面积平均换热系数增加了9.851%，低换热区分布受激波强度与范围主导。

The classic PW-E3 transonic turbine blade serves as the research object in this study. Focusing on the high-load transonic turbine blade tip region, the aerodynamic and heat transfer characteristics under different tip clearances, as well as their underlying mechanisms, were systematically analyzed by solving the three-dimensional Reynolds-Averaged Navier-Stokes (RANS) equations with the SST turbulence model. The research reveals the formation, distribution, and evolution of complex flow structures, shock waves, and expansion waves in the blade tip region. The results show that the subsonic-to-supersonic transition in the tip region significantly influences local pressure, velocity, and heat transfer distributions. Interaction between expansion waves and shock waves leads to irregular bands of high and low heat transfer on the wall surface. As the tip clearance increases, the supersonic region expands, shock wave and separation bubble structures are enhanced, and the area-averaged heat transfer coefficient rises accordingly. When the tip clearance increases from 0.23 mm to 1.38 mm, the area-averaged heat transfer coefficient increases by 9.851%. The distribution of low heat transfer regions is mainly governed by the strength and extent of shock waves.