轮缘密封对下游动叶冷却特性的影响
Influence of Rim Seal on Cooling Characteristics of Downstream Rotor Blade
于飞龙 1何伟 1张蒙 1肖俊峰1
作者信息
- 1. 西安热工研究院有限公司,陕西 西安 710032
- 折叠
摘要
为了探究轮缘密封气流对下游动叶片流场及气膜冷却作用的影响,以某重型燃气轮机透平第 1 级动静叶片为研究对象,采用SST湍流模型求解RANS方程组,在密封流量比(MFR)为0.25%,0.5%,0.75%和1%工况下开展数值研究,对比分析了有/无前缘气膜冷却条件下密封气流对主流流动、动叶片换热性能及通道内涡系结构的影响规律.结果表明:密封气流降低动叶片端壁温度的区域位于叶片前缘至流向约40%弧长距离范围内;自叶根至叶顶方向动叶片吸力面冷却效率先增大后减小;密封气流对动叶片吸力面冷却效率提高最大的位置为前缘至尾缘约50%弧长距离位置;有前缘气膜冷却、MFR为0.5%及以上时密封气流可明显降低端壁温度.
Abstract
In order to investigate the influence of rim seal airflow on the flow field and film cooling effect of downstream rotor blade,the first stage rotor and stator blades of a heavy gas turbine were taken as the research object.The RANS equation set was solved using the SST turbulence model,and numerical stud-ies were conducted at four kinds of ratios of sealing flow rate to mainstream flow rate(MFR),including 0.25%,0.5%,0.75%and 1%.Comparative analysis was conducted on the influence of sealing flow on mainstream flow,heat transfer performance of rotor blade and vortex structure in the channel with and without leading edge film cooling conditions.The results show that the area where the sealing flow re-duces the temperature of the rotor blade endwall is within about 40%of the arc distance from the leading edge of the blade to the flow direction.The cooling efficiency of the suction surface of the rotor blade in-creases first and then decreases from the blade root to the tip direction.The position where the sealing flow improves the cooling efficiency of the suction surface of the rotor blade to the greatest extent is about 50%of the arc distance from the leading edge to the trailing edge.When there is a leading edge gas film cooling structure and MFR is 0.5%or higher,a significant cooling effect is produced on the endwall by the sealing flow.
关键词
轮缘密封/透平动叶/冷却效率/数值研究Key words
rim seal/turbine rotor blade/cooling efficiency/numerical study引用本文复制引用
基金项目
国家科技重大专项(J2019-Ⅰ-0003-0004)
出版年
2024
NETL
NSTL
万方数据