动力机械与工程研究硕士论文：研究有关低雷诺数低压涡轮的气动性能
目录：
摘要 3-4
Abstract 4
第1章绪论 7-14
1.1引言 7
1.2低压涡轮的特点 7-8
1.3国内外在该方向的研究现状及分析 8-13
1.3.1低压涡轮目前的研究状况 8-9
1.3.2低雷诺数对低压涡轮叶片边界层及设计思路的影响 9-11
1.3.3优化设计方法综述 11-12
1.3.4目前低压涡轮设计中的一些问题 12-13
1.4本论文主要研究内容和目的 13-14
第2章低压涡轮低雷诺数三维粘流计算方法与验证 14-20
2.1引言 14
2.2实验验证叶片的分析 14-19
2.2.1实验验证叶片的选择 14-15
2.2.2计算用湍流模型的选择 15-18
2.2.3计算用转捩模型的选择 18-19
2.3本章小结 19-20
第3章雷诺数改变对低压涡轮气动性能的影响 20-33
3.1引言 20
3.2计算对象和数值方法 20-22
3.3计算结果分析 22-32
3.3.1总体参数分析 22-23
3.3.2一维参数与准三维参数分析 23-32
3.4本章小结 32-33
第4章不同马赫数对低雷诺数低压涡轮的影响 33-66
4.1引言 33-34
4.2出口马赫数为1工况下，不同雷诺数性能分析 34-41
4.2.1计算条件 34
4.2.2能量损失系数 34-35
4.2.3叶片表面静压分布 35-37
4.2.4端壁极限流线 37-39
4.2.5中径马赫数等值线 39-41
4.3出口马赫数为1.2工况下，不同雷诺数性能分析 41-48
4.3.1计算条件 41
4.3.2能量损失系数 41-42
4.3.3叶片表面静压分布 42-45
4.3.4端壁极限流线 45-46
4.3.5中径马赫数等值线 46-48
4.4不同马赫数下气动性能比较 48-65
4.4.1Re=3.5×10~4，不同马赫数气动性能 48-54
4.4.2Re=3.5×10~5，不同马赫数气动性能 54-59
4.4.3Re=3.5×10~6，不同马赫数气动性能 59-65
4.5本章小结 65-66
第5章低雷诺数低压涡轮提高效率的方法及优化 66-75
5.1引言 66
5.2提高雷诺数减少叶栅损失 66-68
5.3低雷诺数条件下减少损失的研究 68-73
5.3.1弯叶片优化 68-70
5.3.2低压涡轮静叶片积叠优化分析 70-73
5.4本章小结 73-75
结论 75-76
参考文献 76-81
致谢 81
【摘要】 低压涡轮是航空发动机的重要组成部分,多级的低压涡轮融汇了先进的空气动力学和机械设计特性。低压涡轮的重量占到整个航空发动机总重量的1/3,是决定总成本的一个重要部分。低压涡轮作为航空发动机的重要部件,其性能的改进对发动机整体性能的提高有着至关重要的影响。低压涡轮在高空低雷诺数条件下运行,受低雷诺数条件影响较大,在低雷诺数条件下效率有所降低。在巡航条件下的低压涡轮是在0.8×105到3.0×105的低雷诺数工作,气体在涡轮叶片表面的雷诺数甚至可以达到105以下。这时的叶片后面的扩散可能会导致附面层很厚,使得低压涡轮的性能减弱。本文对某型航空发动机低压涡轮末级进行了不同雷诺数条件下的计算分析,对比了不同雷诺数条件下该级涡轮的气动性能。通过计算分析,可以看出,高雷诺数条件相比,在低雷诺数条件下,低压涡轮效率明显降低,损失增大,负荷降低,附面层变厚,马蹄涡、通道涡损失增加。本文还对该级涡轮进行了在不同马赫数下、不同雷诺数下的计算分析,主要分析了能量损失、叶片表面静压分布、端壁极限流线、激波和附面层相互作用等气动现象。可以看出,在同马赫数、不同雷诺数条件下,低雷诺数损失都升高,超音速条件下,激波与附面层作用明显。本文还对在低雷诺数条件下如何提高低压涡轮效率进行了理论分析,并做了周向积叠优化。通过分析可以看出,采用弯叶片积叠,能够有效降低损失。
硕士论文代笔【Abstract】 Low pressure turbine is an important component of the aero-engine, and the multi-stage low pressure turbine integrates advanced aerodynamics and mechanical features. The weight of low pressure turbine accounts for one-third of the total weight of the aero-engine, which is an important part of the total cost. As an important part, the improvement of the performance of the low pressure turbine impacts vitally to the overall performance improvement. Low pressure turbine operates at high altitude at low Reynolds number, which the low Reynolds number condition has a great impact on, and it has a lower efficiency. Under the cruise condition, low pressure turbine works from 0.8×105 to 3.0×105 of Reynolds number, while at the surface of the blade the Reynolds number is even under 105. Then the diffuse behind the blade can cause the boundary layer thicker, which can decrease the performance of the low pressure turbine.This thesis calculates and analyzes the last stage of the low pressure turbine of an aero-engine at different Reynolds numbers, and compares the aerodynamics performances. By the calculations and analyses, it can be seen that the efficiency and the load decreases greatly, the loss increases, the boundary layer gets thicker, and the loss of horseshoe vortex enhances compared with the condition of the one at high Reynolds numbers.The thesis also calculates and analyzes this stage of low pressure turbine at different Mach numbers and different Reynolds numbers. It mainly analyzes some aerodynamics phenomenon, such as the loss of energy, the distribution of the surface of the blade, limited streamline, the interaction in the shock and the boundary layer, and so on. We can see that at the condition of different Mach numbers and different Reynolds numbers, the loss at low Reynolds number increases, and the interactive in the shock and the boundary layer is obviously.The thesis does theory analyses at the problem of how to increase the efficiency of the low pressure turbine, and optimizes the parameters of the stacking law. Through the analyses, we can see that the adoption of bowed blade can decrease the loss effectively.
【关键词】 低雷诺数； 低压涡轮； 弯叶片；
【Key words】 low Reynolds number； low-pressure turbine； bowed blade；
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