为了揭示叶顶汽封结构变化对泄漏损失的影响，提高汽轮机运行效率，数值研究了平齿汽封、高低齿汽封和侧齿汽封3种不同叶顶汽封结构下汽轮机高压转子间隙泄漏的流动形态、间隙涡系的形成机理和发展规律，研究表明：在叶顶汽封腔室复杂的周向螺旋状的涡动中，泄漏流体的周向速度是影响漩涡耗散的一个重要因素；高低齿及侧齿的汽封结构可以增强漩涡之间的相互作用，降低泄漏流体的周向速度，使漩涡在腔室内的耗散更加充分；由于掺混损失降低，高低齿及侧齿汽封的泄漏总损失较平齿汽封相比分别下降7.1%和9.8%。

In order to reveal the effect of tip seal structure on the leakage loss and improve the efficiency of steam turbine,the flow pattern of leakage clearance,the formation mechanism and development law of clearance vortexes of a high-pressure turbine rotor were investigated by numerical simulation and three different blade tip seal structures,including comb-type seal,stepped labyrinth seal and lateral tooth seal,were taken into account.The results show that the circumferential velocity of leakage flow is one of the important factors which can affect the dissipation of the complex circular spiral vortex in the tip seal cavities.The interaction between the vortexes can be enhanced,the circumferential velocity of leakage flow can be reduced and the vortexes in the cavity can be more fully dissipated by using the stepped labyrinth seal and the lateral tooth seal.The total leakage loss with stepped labyrinth seal and lateral tooth seal is decreased by 7.1% and 9.8%,respectively,compared to the total leakage loss of comb-type seal.

TK263

国家自然科学基金(51576036)