共查询到20条相似文献,搜索用时 4 毫秒
1.
2.
3.
涡轮增压器叶轮流固耦合模态分析 总被引:4,自引:2,他引:2
为了研究流固耦合场对涡轮增压器叶轮模态参数的影响,采用基于湍流模型理论建立了涡轮增压器压气机的流场模型.并进行了流场网格划分和边界条件的加载.通过计算获得了流场内部的流速、压力分布,把流场压力分布加载到叶轮固体表面上,并计算考虑流固耦合场的叶轮模态.计算结果表明,流固耦合场主要影响叶轮结构的模态固有频率,对模态振型的影响较小. 相似文献
4.
5.
6.
7.
涡轮增压器在工作时,高温废气会把大量的热量传递给涡轮叶轮,并通过转轴传递给压气机叶轮。由于压气机叶轮处于常温环境中,受到高温加热的涡轮增压器转子会产生较大的温度梯度。根据涡轮增压器转子的实际结构和工作条件,建立了考虑温度场作用的转子动力学分析模型,对不同工况下涡轮增压器转子动力学特性进行研究和实验验证,揭示了温度场对涡轮增压器转子临界转速和稳定极限转速的影响规律,并根据计算结果对转子结构进行优化。结果表明:温度场使转子一阶临界转速增大,二、三、四阶临界转速降低,使稳定极限转速的阈值降低。从温度场作用方面出发,对高温环境下涡轮增压器转子系统动力学特性进行准确分析及结构改进,对于提高我国涡轮增压器的设计研究水平具有一定的参考意义和工程实践价值。 相似文献
8.
9.
以计算流体力学(Computational Fluid Dynamics,CFD)理论为基础,采用双向流固耦合的方法对增压器涡轮流场进行了数值模拟。通过数值模拟计算得出涡轮出口温度,并与实验值进行对比,其最大误差不超过3. 6%,验证了数值模拟的准确性;由于涡轮增压器叶轮的高熵值区域比较多,并且分布不均匀,因此对涡轮叶型进行了改进,结果表明:改进后叶轮的总体熵值和高熵值区域有所减小,且分布比较均匀;涡轮出口处温度相比之前降低了约30 K,说明改进后的叶轮做功比原叶轮更多,涡轮效率提高了6. 8%。 相似文献
10.
11.
12.
涡轮机械的非均匀进口来流会使得涡轮的流场不均匀,从而影响涡轮的工作性能。本文根据涡轮的工作机理,建立了存在叶尖间隙的涡轮流动模型,考虑来流的周向非均匀性,研究了涡轮流场的变化规律,讨论了不同来流参数对涡轮流场参数的影响。 相似文献
13.
14.
15.
针对叶轮进口宽度对液力透平性能影响规律的认识不足问题,建设了一开式液力透平实验台,对一单级液力透平进行了实验研究,得到了该比转速液力透平的外特性曲线。采用结构化网格技术对液力透平进行了全流场数值计算与分析,数值与实验相结合,验证了数值计算的准确性。对不同进口宽度透平叶轮的数值计算结果分析表明,随着透平叶轮进口宽度的增加最高效率点向大流量偏移,大流量时的效率逐渐增加;对于一定几何参数组合的液力透平,存在最佳叶轮进口宽度使液力透平最优工况点效率最高;透平的流量扬程曲线随叶轮进口宽度的增加变得更加平坦;透平的轴功率变化相对较小。 相似文献
16.
The internal flow fields of two automotive Plexiglas torque converter turbines with three different pumps were examined. A laser velocimeter was utilized to measure the velocity flow field at the turbine inlet and mid-planes in the six different geometry combinations; the stator was the same for all combinations. The turbine geometries differed only by the inlet blade angle, while the pump geometries differed only by the exit blade angle. The torque converter was operated at three different turbine/pump rotational speed ratios: 0.065 (near stall), 0.600, and 0.800 (near coupling point). For all geometries at the inlet plane the flow is fairly uniform in the blade-to-blade direction at all speed ratios. Velocities are most uniform in the core-to-shell direction at high speed ratios, but high velocities move near the shell at lower speed ratios. At the mid-plane, at low speed ratios the velocities are significantly higher near the pressure surface but as the speed ratio increases, the gradient decreases. At low speed ratios velocities are higher near the shell but this distribution becomes uniform at higher speed ratios. In general the flow became more uniform as the speed ratio increased. Variations in the pump exit blade angle had effects on both inlet and mid-plane velocity distributions and are documented. Variations in turbine inlet blade angle altered the inlet and mid-plane flow fields, but less so than the pump variations. A clockwise circulatory secondary flow pattern at the turbine inlet plane was observed for all geometries and, conversely, counter-clockwise circulatory secondary flow patterns at the mid-plane were recorded. Resulting vorticities were found to depend on geometries and speed ratios. The turbine leading edge incidence angles were found to strongly depend on the speed ratio, ranging from positive to negative, as well as pump and turbine blade angles. 相似文献
17.
涡轮增压器在航空航天、船舶、汽车等工业已经大量的应用,其中涡轮是较为重要的构件,目前对涡轮强度的分析还较少。根据涡轮增压器研制要求,利用MSC.Nastran对该涡轮增压器轴流涡轮在最高结构转速及温度场耦合作用下涡轮的应力、位移情况,并且考虑涡轮前后不同进出温度温度对涡轮的影响。经过分析,涡轮及叶片在不同温度和最高转速作用下,并未发生屈服,满足力学安全性,为该涡轮增压器轴流涡轮的设计、制造提供参考。 相似文献
18.
将粒子图像测速仪(PIV)和热线风速仪(HWA)应用到低速轴流平面叶栅实验台上.在2个不同进口流量和3个不同叶片高度下,利用热线风速仪测量平面叶栅出口瞬态速度场,并采用激光粒子图像测速仪测量圆柱尾迹和出口速度场的整场信息.研究发现较大的进口速度或较低的叶片高度情况下,叶栅出口二次流流动强烈;同时发现尾迹的存在会破坏均匀流场,导致叶型流动损失的增加. 相似文献
19.
通过在涡轮盘腔内部增加叶片的方式改变盘腔内部流动结构,从而降低旋转系下的相对总温.针对不同叶片结构对涡轮盘腔内部流动的影响开展数值模拟研究.结果表明:叶片叶型结构设计对内部流场的影响较大,旋流比为影响的主要因素,旋流比接近于1时,增压温降效果最好;导流叶片叶型的差异对总温降增压效果的影响明显;叶片进出口半径对预旋系统整... 相似文献
20.
Jong Joon Lee Jae Eun Yoon Tong Seop Kim Jeong L. Sohn 《Journal of Mechanical Science and Technology》2007,21(1):141-152
This study aims to analyze engine performance and component characteristics of a micro gas turbine based on detailed measurement
of various parameters. A test facility to measure performance of a micro gas turbine was set up and performance parameters
such as turbine exit temperature, exhaust gas temperature, engine inlet temperature, compressor discharge pressure and temperature,
and fuel and air flow rates were measured. The net gas turbine performance (power and efficiency based on the gas turbine
shaft end) was isolated and analyzed. With the aid of measurement based simulation, component characteristic parameters such
as turbine inlet temperature, compressor efficiency, turbine efficiency and recuperator effectiveness were estimated. Behaviors
of the estimated characteristic parameters with operating condition change were examined and sensitivities of estimated parameters
to the measured parameters were analyzed. 相似文献