【作者】 于景磊；

【导师】 徐立民；

【作者基本信息】 中国舰船研究院 ， 轮机工程， 2011， 硕士

【摘要】 由于工质的差异性,采用空气常规设计方法的氦气压气机存在单级压比过小的问题。经验证,适用于氦气的大转折角叶型叶栅可使级负荷成倍增加;氦气压气机采用新型基元级设计方法,实现了提高压比,减少级数的目的。本文采用NUMECA的Fine/turbo软件包对5个参变量组合构成的324种新型平面叶栅进行了数值模拟研究,对结果数据进行关联研究,并得到了各参数反映损失规律性的最佳方案,在此基础上,计算了5个参量组合下162种新型基元级的性能。研究结果表明:常规设计下的扩压因子反映叶栅损失的规律在高负荷叶栅下不再适用;相同损失系数条件下,存在一个临界进气角使气流转折角达到最大,该临界进气角几乎仅与稠度相关;在较大稠度时,叶型最大厚度比变化对损失的影响十分可观,应用薄叶型很有利;新型基元级负荷得到大幅度提升,并且级效率还能维持在较高的水平。基于平面叶栅和基元级数值计算数据,设计了高负荷三维级和与之对比的常规三维级,并进行三维级数值模拟,模拟结果显示:该新型设计下的三维级方案是可行的,一个高负荷三维级设计方案:中径的马赫数0.465、能量头系数1.0、流量系数1.141、反动度0.5、稠度1.475,设计点的级压比达到1.1388,级效率达到89.86%,90%设计流量点的级压比和级效率为1.137和90.05%,110%设计流量点的级压比和级效率为1.139和88.99%,而作为比较的常规设计方案:中径的马赫数0.281、能量头系数0.419、流量系数0.5998、反动度0.5、稠度1.475,设计点的压比为1.067,效率为87.78%。更多还原

【Abstract】 As a result of working fluids’difference, there is a problem that the pressure ratio of single stage of the helium compressor designed according to conventional air-compressor rule will be smaller. By way of the verification, the high-turning-angle cascade suitable for helium can make the stage-load level increasing; the helium-compressor using this new stage design method, has realized the improving compression ratio, reducing series.In this paper 324 new-type cascades composed of the five parameters combination are simulated by the software Fine/turbo made by NUMECA, and the data of results is studied associatedly. Based on this, 162 types of stages composed of the five parameters combination are calculated. The results of the study indicate that: the rule that the diffusion factor reflects the pressure loss under conventional design in high-load cascade is no longer applicable; under the same loss coefficient conditions, there is a critical inlet-airflow angle making the turning-angle to achieve maximum, this critical intake angle almost only related with solidity; In larger solidity (1.15 and 1.5), the blade maximum thickness ratio affects the loss considerably, applicating of thin blade is advantage; the load of the new stage is greatly enhanced, and the efficiency can maintain at a higher-level. Research data can lay a foundation for further research on high-load helium-compressor.Based on the data of the calculation about cascades and stages, the high-load three-dimensional stage and the conventional three-dimensional stage compared to are designed. And the flow of the three-dimensional stage is simulated. Simulation results show that, the project of this new three-dimensional stage design is reasonable. There is a project of the high-load three-dimensional stage that in the middle of the radius every parameter is respective that inlet Mach number is 0.465, the energy coefficient is 1.0, the flux coefficient is 1.141, the reaction is 0.5, the solidity is 1.475. The pressure ratio reaches 1.1388, the stage efficiency is 89.86% as a simulated result under the design condition. The pressure ratio and the stage efficiency is respective 1.137 and 90.05% under the 90% of the design flux. The pressure ratio and the stage efficiency is respective 1.139 and 88.99% under the 110% of the design flux. And that, compared to it, there is a project of the normal three-dimensional stage that in the middle of the radius every parameter is respective that inlet Mach number is 0.281, the energy coefficient is 0.419, the flux coefficient is 0.5998, the reaction is 0.5, the solidity is 1.475. The results of normal design are that the pressure ratio is 1.067, the stage efficiency is 87.78% under the design condition.更多还原