为了研究叶冠与篦齿参数对末级带冠长叶片叶顶流动与损失的影响,选取某300MW重型燃气轮机涡轮的末级带冠动叶为研究对象,采用数值模拟的方法研究了叶顶间隙、出口空腔长度、篦齿数量3个几何参数对末级带冠长叶片流动与损失的影响规律,分析不同几何参数对末级带冠长叶片叶顶流动的影响机理。结果表明：不同叶冠与篦齿参数对末级带冠长叶片流动与损失的影响程度与机理均不同。叶顶间隙变化造成的影响最为显著,叶顶间隙的增大造成叶冠泄漏流量与损失的急剧增大；出口空腔长度的增大造成叶冠内部损失的增大,但却减小了叶冠出口端壁区域的回流区；篦齿数量的增加提高了篦齿对流体的阻碍封严能力,从而降低叶冠出口损失。

In order to study the effect of shroud and labyrinth seal parameters on flow and loss at the tip of the last turbine stage shrouded long blade, the last stage shrouded rotor blade of a 300MW heavy duty gas turbine was selected as the research object. The effects of three geometric parameters, including tip clearance, outlet cavity length and labyrinth seal number, on the flow and loss of the last stage shrouded long blade were studied by numerical simulation method, and the influence mechanism of different geometric parameters on the tip flow of the last stage shrouded long blade was analyzed. The results show that different shroud and labyrinth seal parameters have different effects and mechanism on the flow and loss of the last stage shrouded long blade. The most significant effect is caused by the change of the clearance of the blade tip. The increase of blade tip clearance caused the sharp increase of shroud leakage flow and loss. The increase of the outlet cavity length caused the increase of the internal loss of the shroud, but it reduced the reflux area of the end wall area of the shroud outlet. The increase of the number of labyrinth seals improves the blocking and sealing ability of the labyrinth seals to the fluid, thereby reducing the outlet loss of the shroud.

xxx

黑龙江省优秀青年基金(YQ2021E023)