【作者】 闫磊；

【导师】 刘学义；

【作者基本信息】 哈尔滨工程大学 ， 轮机工程， 2009， 硕士

【摘要】 冷却预旋输气系统是燃气轮机内冷却装置的重要组成部分,在冷却气体从压气机输送到涡轮叶片的过程中,由静止机匣输送到高速旋转的涡轮盘的压力损失最大。预旋输气系统的作用就是尽可能减小冷却气体在这个过程中的压力损失,并且可以降低冷却气体的温度,改善冷却效果。预旋输气系统主要由三部分组成：稳压整流腔、预旋喷嘴和涡轮盘中的冷却气体通道。稳压整流腔的作用是将来自压气机的冷却空气混合均匀并减轻不确定的压力波动；预旋喷嘴与涡轮中静子的作用相似,气体在其中减压加速并改变方向,为进入高速旋转的涡轮盘做准备；涡轮盘中的冷却通道角度必须迎合气体的来流方向,如果不匹配就会导致压力损失的急剧增大。一个高效率的预旋输气系统需要这三个部件间的完美匹配。本文以国内某型燃气轮机冷却预旋输气系统为原始模型,通过数值模拟来了解预旋输气系统的流场特性,探索改良的方法。本文主要完成了以下三方面的工作：1、详细分析了预旋输气系统的物理模型并对其进行了适当的简化。建立了计算模型并数值模拟,获得了预旋系统较完整的流场分布情况而且进行了详尽的说明。2、将数值模拟的结果同实际数据做比较,找出计算模型简化不合理的地方,尝试进行改进,使计算结果更接近真实值,并以此作为优化模型的计算基础,让数值仿真更有实用价值。3、通过流场分析找出对阻力影响较大的部分并对其优化,计算优化模型,对其结果与未优化模型作比较,得出一些实用的结论。更多还原

【Abstract】 Cooling air pre-swirl input system is the most important part of gas turbine cooling system. Cooling air has lost the most pressure in the course of transporting cooling air from stationary components to high-speed rotating turbine disk channel.Its function is to reduce the pressure lost as more as possible and drop the temperature of cooling air,improving cooling effect.Pre-swirl input system mainly comprises three parts:pressure regulate cavity, pre-swirl nozzles and receive channel in turbine disk.The function of pressure regulate cavity is to mix the cooling air and lighten uncertain pressure wave from compressor.Pre-swirl nozzle is like stationary blades in turbin component.In this part,cooling air release its pressure,accelerate and change direction.The angle of receive channel in turbine disk must mach the direction of nozzle flow.There will be rapid increase of pressure loss if they’re not matched.An efficient pre-swirl transport system needs the perfect match of these three components.In this paper, a cooling air pre-swirl input system of a certain type gas turbine domestic as original model, using numerical simulation to describe the characteristics of inside flow to explore the change of structure in order to make it better. This paper is mostly complete the following three aspects:1、Analysis the physical model of pre-swirl input system particularly and found calculation model, then conduct an appropriate simplification. The establishment of calculation model has been numerical simulate, get the entire flow field of pre-swirl input system, describe and analyze it.2、Compare the results of numerical simulation with the actual data, identify the limitation of this numerical model. Then make improvements, to make sure that numerical simulate results closer to the actual data, and use it the foundation of the improving models, make the numerical simulation more valuable.3、Identify the most affected part of the pressure loss through the flow field analysis, improve it. Then numerical simulate improved models, make a comparison with original model, reach a conclusion.更多还原