|
| 小展弦比调节级动叶栅二次流数值模拟与损失特性 |
| Numerical simulation of secondary flow in governing stage rotor cascade at low aspect ratio and its loss characteristics |
| 投稿时间：2023-05-18 |
| DOI：10.13259/j.cnki.eri.2024.04.006 |
| 中文关键词: 汽轮机 调节级 气动性能 二次流损失 数值模拟 |
| 英文关键词:steam turbine governing stage aerodynamic performance secondary flow loss numerical simulation |
| 基金项目:国家自然科学基金资助项目（51106099） |
|
| 摘要点击次数: 1417 |
| 全文下载次数: 1017 |
| 中文摘要: |
| 工业汽轮机调节级叶栅展弦比较低，且经常在变工况下运行，导致叶栅效率降低。针对这一问题，采用数值方法对某调节级35TP–0A–78°动叶栅三维流场进行计算，展弦比为0.25 ～ 3.00、来流冲角i在–80° ～ 20°范围变化时，研究叶栅的气动性能及二次流损失特性。研究结果表明，随着展弦比的增大，平均能量损失系数从0.148降低到0.080，降低了46%。当展弦比 ≤ 1.00时，叶栅内部三维流动特性明显，且随着展弦比降低，上、下通道涡自叶栅通道端壁向叶栅中部移动，二次流损失剧增。对于展弦比为0.50的动叶栅，冲角i从0°沿正向变化到20°时，平均能量损失系数从0.073增加到0.188，相对增加了1.57倍。冲角i从0°沿负向变化到–80°时，平均能量损失系数从0.073增大到0.172，相对增加了1.36倍，此时叶栅压力面前半部出现大范围流动分离。对于本文研究的计算模型，动叶栅展弦比在2.00～ 3.00、冲角在–10° ～ 0°范围内，叶栅总能量损失较低，具有较好的气动性能。 |
| 英文摘要: |
| The governing stage cascade of industrial steam turbines has a low aspect ratio, which decreases the cascade efficiency under variable operation conditions. To address this issue, the three-dimensional flow field of a governing stage 35TP-0A-78° rotor cascade was obatined using numerical simulation method. The influence of aspect ratio (0.25 ~ 3.00) and inflow angle (–80° ~ 20°) on the aerodynamic performance and secondary flow loss characteristics of the cascade were studied. Results show that with the increase of aspect ratio, the average energy loss coefficient decreases from 0.148 to 0.080, reducing by 46%. At the aspect ratio ≤ 1.00, the obvious three-dimensional flow characteristics are found in the cascade, and as the aspect ratio decreases, the upper and lower channel vortices move from the end wall of cascade channel to its middle, which causes the sharp increase of secondary flow loss. For the rotor cascade with the aspect ratio of 0.50, when the incidence angle i changes positively from 0° to 20°, the average energy loss coefficient ascends from 0.073 to 0.188, increasing by 1.57 times. When the incidence angle i changes negatively from 0° to –80°, the average energy loss coefficient increases from 0.073 to 0.172, ascending by 1.36 times, and the flow separation occurs largely in the first part of cascade pressure surface. For the calculation model in this paper, the rotor cascade has low total energy loss and good aerodynamic performance at the aspect ratio of 2.00 ~ 3.00 and the incidence angle of –10° ~ 0°. |
| HTML 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|
