DERA的核心压气机发展验证计划

对DERA的核心压气机发展验证计划作了简要介绍,重点围绕核心压气机设计研制思想、方法和设计研究体系的发展验证,分析和说明了已取得的各项进展。最后对这一研究计划的意义进行了分析和讨论。     

一种分析稳态压力畸变对多级轴流压缩系统稳定性影响的新方法

发展了一种分析进口稳态压力畸变对多级轴流压缩系统稳定性影响的逐级平行压缩系统模型；建立了一种稳态压力畸变进气条件下，多级轴流压缩系统对燃烧室燃油瞬时脉冲的气动响应及气动稳定性分析的新方法；导出了基于ＭａｃＣｏｒｍａｃｋ隐式格式的新的数值计算方法。应用新的模型方法对一个三级实验压气机进行了数值分析，给出了稳态压力畸变与压缩系统稳定裕度损失及不稳定发生时间之间的定量关系，定量给出了压气机失稳首发级的识别方法。     

一种整体式天然气压缩机气阀故障诊断技术研究CSCD

整体式天然气压缩机在石油化工领域广泛应用,压缩机的正常工作对安全生产具有重要意义。为了有效诊断整体式压缩机气阀部件的故障,采用了Daubechies小波基函数对ZTY470型整体式天然气压缩机气阀振动信号的分解重构原理,详细介绍了以振动信号的能量为故障特征的故障诊断过程。对气阀阀片断裂和弹簧断裂的故障振动信号进行了小波包分析,并与正常工作时的信号进行了对比。实验表明该方法能准确的进行故障诊断和故障定位,证明了对整体式天然气压缩机气阀故障诊断的有效性。     

压气机叶片型面精密数控铣加工技术应用研究

为了提高压气机叶片型面和进、排气边转接圆角的数控铣加工质量,在工艺、夹具、数控加工模型与程序以及检测方法等方面采取了攻关措施,减小了叶片型面精铣加工的变形,实现了叶身型面的精密铣削加工,对型面采用毡轮修光去除铣削痕迹后,经过3坐标、小半径投影仪等设备的测量,进、排气边转接圆角的形状和型面轮廓度、位置度各项要求的加工质量得到了质的提升,其合格率由20％提高到75％以上,加工效率和刀具耐用度提高1倍以上,使叶身型面精密铣削技术具备了精品叶片批量生产的工程化应用技术基础.     

离心叶轮全三维反问题方法设计误差稳定性研究

用流线曲率全三维反问题方法和引入滑移因子模型的准三维流线曲率反问题方法设计了叶片数不同的和增压比不同的小型高速离心叶轮.用商用计算流体力学(CFD)求解器估算了这些叶轮的性能.对比了这两种反问题方法的设计误差稳定性,考察了分流叶片对设计误差的影响.结果表明,流线曲率全三维反问题方法能够根据叶片负荷对叶片设计做出恰当调整.较准三维反问题方法,流线曲率全三维反问题方法所设计叶轮的增压比普遍偏高.随叶片负荷增加,较准三维反问题方法,流线曲率全三维反问题方法的设计误差变化较小,即其设计误差稳定性明显较好.分流叶片对准三维反问题方法设计结果的影响明显较小.      

Effect of blade tip winglet on the performance of a highly loaded transonic compressor rotor

The tip leakage flow has an important influence on the performance of transonic com-pressor. Blade tip winglet has been proved to be an effective method to control the tip leakage flow in compressor, while the physical mechanisms of blade tip winglet have been poorly understood. A numerical study for a highly loaded transonic compressor rotor has been conducted to understand the effect of varying the location of blade tip winglet on the performance of the rotor. Two kinds of tip winglet were designed and investigated. The effects of blade tip winglet on the compressor over-all performance, stability and tip flow structure were presented and discussed. It is found that the interaction of the tip winglet with the flow in the tip region is different when the winglet is located at suction-side or pressure-side of the blade tip. Results indicate that the suction-side winglet (SW) is ineffective to improve the performance of compressor rotor. In addition, a significant stall range extension equivalent to 33.74% with a very small penalty in efficiency can be obtained by the pressure-side winglet (PW). An attempt has been made to explain the fundamental mechanisms of blade tip winglet in detail.     

导风轮叶片偏置对高压比串列离心压气机性能的影响

为提升高压比串列离心压气机的性能,借鉴常规一体化离心叶轮中偏置分流叶片的方法,针对某高压比串列离心压气机,应用数值仿真手段分析了串列叶轮中导风轮叶片周向偏置对压气机流场和性能的影响。通过对不同导风轮叶片偏置方案下压气机流场的分析,建立了压气机流动损失与偏置参数的关联性。研究表明:采用较大的偏置参数γ可降低导风轮叶片1前缘的激波强度,改善激波作用导致的泄漏涡破碎和流动分离,但过大或过小的γ方案中导风轮叶顶会出现二次泄漏致使低能流体的掺混损失增加;γ=65%方案压气机综合性能最佳,其压比和效率较γ=50%分别提高了1.5%和1.4%;对于串列离心压气机导风轮叶片周向位置的优化,在避免导风轮叶顶形成较强二次泄漏的前提下,应考虑采用较大的偏置参数γ,同时应防止诱导轮尾迹流体参与导风轮的叶顶泄漏。     

Cross-sectional deformation behavior of double-ridged rectangular tube with fillers in different stages of H-typed bending

The bent double-ridged rectangular tube (DRRT) with high forming quality is helpful to improve the microwave transmission accuracy. For reducing the cross-sectional deformation in the H-typed bending process, in addition to using rigid mandrel to support the inside of tube, ridge groove fillers are also added to restrict the deformation of ridge grooves. Because of the change of stress and strain state of bent tube in bending, rigid mandrel retracting and specially twice-springback stages, and the springback of fillers, the cross-sectional deformation of tube in each stage may be different. Therefore, based on the ABAQUS platform, the finite element models (FEM) for H-typed bending, mandrel retracting and twice-springback stages of H96 DRRT with fillers were established and validated. It is found that, for the height and width deformation of tube and spacing deformation of ridge grooves, retraction of mandrel can make the distribution of these deformations more uniform along the bending direction. The first springback can reduce these deformations significantly, which should be emphasized. But the second springback only increases them by less amount, which can be ignored. The smaller height deformation of ridge groove and filler can be neglected.     

等离子体气动激励抑制压气机叶栅角区流动分离的仿真与实验

进行了等离子体气动激励抑制低速压气机叶栅角区流动分离的数值仿真研究,并进行了实验验证.小攻角情况下,叶片吸力面角区流动分离导致显著的尾迹总压损失.来流速度为50 m/s(雷诺数为223 000)时,等离子体气动激励可以有效的抑制角区流动分离,降低总压损失.激励电压、频率分别为10 kV和22 kHz时,50%叶高处的尾迹压力分布基本不变,60%和70%叶高处的最大总压损失分别减小了13.83%和10.74%.增加激励电极组数或激励电压,可以增强抑制效果.      

端壁造型技术在亚声轴流压气机级中的应用

为探索利用端壁造型技术来提高轴流压气机性能的可能性,以亚声轴流压气机试验级为对象,对端壁造型技术在压气机中的应用进行了研究.鉴于压气机的逆压工作环境,端壁设计结合了周向(非轴对称)和流向两个方向的造型,具体介绍了造型方法.对端壁造型后压气机级的数值模拟显示:端壁造型技术可以有效减小、消除静子角区分离,进而提高级的效率和压比.