基于LabVIEW的离心压缩机动态压力测试系统研究

从分析表征离心压缩机喘振发生时的动态压力特性入手,揭示离心压缩机的出、入口及叶轮处的动态压力信号对研究压缩机喘振主动控制的重要意义。随后在800 k W离心压缩机系统上设计了动态压力测量的NI测试系统,并用Lab VIEW进行软件开发和实现。为致力于研究离心压缩机系统特性、喘振机理及主动控制方法的工程技术人员提供了搭建测试系统的设计原则和实现方法,具有重要的参考价值。     

基于气腔模型和节流阀模型的离心压缩机喘振数值研究（英文）

本文结合气腔模型和节流阀模型建立了一种离心压缩机与管网系统的关联模型,该关联模型实现了压缩机从稳态到喘振的数值模拟。通过关联模型对离心压缩机内部流场进行了三维非定常数值研究,对叶轮流道和扩压器内的流动结构进行了绘制和分析。研究了压缩机出口压力及出口质量流量随时间的波动变化,分析了喘振工况下压缩机-管网系统的特性变化,讨论了出口阀门系数、背压等参数对喘振的影响。     

某工业用离心式压缩机失速和喘振识别试验研究

失速和喘振识别对于离心式压缩机喘振控制线的设定起非常重要的作用。通过对某工业用离心式压缩机的压力脉动测试,找到了该机组在不同转速下的失速或者喘振工况点。试验结果显示,通过识别频域中的特征频率,能够识别失速和喘振工况。对于本文研究对象的离心压缩机,随着流量的降低,在低转速运行时,旋转失速先于喘振发生;在高转速运行时,旋转失速和喘振几乎同时发生。     

单缸多段抽加气离心压缩机组防喘振控制方案设计

针对单缸多段离心压缩机组设计过程中遇到的技术难点——多段抽加气防喘振控制计算方案的确定,通过分析乙烯装置丙烯机组单缸多段抽加气压缩机中防喘振、防阻塞控制的特点,同时考虑多种因素影响,对常规算法进行补充优化,提出区别以往常规的多段缸内混合气体防喘振控制计算方法,设计并实现单缸多段抽加气离心压缩机的防喘振控制算法的解决方案。     

离心式压缩机喘振工况的危害与控制

介绍了离心式压缩机特殊的喘振工况及危害性,叙述了离心式压缩机进入喘振工况的判断方法和诱发喘振的因素,最后阐述防止离心压缩机发生喘振的控制措施。     

压气站压缩机组负荷分配方案分析与实现

针对长输管道压气站离心压缩机组在并联运行时负荷分配操作调整难度大,控制调整波动大等问题,先从理论上分析了常见的3种并联离心压缩机组负荷分配方案的原理,通过对比分析传统负荷分配方案负荷分配控制效果,制约条件及不足之处,提出了等喘振裕量负荷分配技术方案即控制操作点与喘振控制线等距离。最后以中亚管道某压气站为例,介绍了压气站等喘振裕量负荷分配在某同型机组上的工程实现。研究表明:压缩机等喘振裕量负荷分配方法不但适用于各种不同的机型,而且机组喘振风险低,机组运行效率提升,是应优先选用的压缩机负荷分配控制方案。     

离心压缩机防喘振控制标准模块的开发

基于国内外比较先进的离心压缩机防喘振控制方案,结合多年的项目开发经验,采用中小型PLC控制系统开发出防喘振控制标准模块,实现了动态防喘振控制。     

亚音速径向离心压缩机喘振及防喘叶栅

一、前言本文根据单级离心压缩机的设计试验情况,研究径向离心压缩机的喘振原因、叶片扩压器能否引起喘振以及不用调节如何将喘振点大幅度向小流量区移动等问题。试验所用压缩机系半开式径向离心压缩     

离心压缩机机壳在基频气动力激励下的振动噪声研究

研究了离心压缩机机壳在内部基频气动力激励下的振动辐射噪声。考虑机壳与轮盘、轮盖之间的间隙,采用SSTk-co湍流模型模拟了离心压缩机的整机三维非定常流场,得到蜗壳内表面的脉动压力,然后将脉动压力的基频部分加载到蜗壳上,模拟离心压缩机蜗壳在非定常气动力激励下的振动噪声。研究表明：机壳内壁面基频压力脉动主要分布在无叶扩压器靠近叶轮出口一侧;机壳主要基频振动噪声源位于蜗壳靠近出口管道一侧;该离心压缩机机壳基频振动位移幅值很小,最大振动位移仅为11．8×10^-9m,因此可以忽略机壳的基频振动对离心压缩机运行安全性的影响。     

并联压缩机组节能改造技术及应用

本文主要对压缩机尤其是并联离心压缩机组的节能改造技术进行了介绍,结合改造实例,对并联离心压缩机组通过变速调节及调节压缩机防喘振阀开度等方法实现节能改造进行了详细的阐述。     

离心压气机机匣处理多工况性能预测与分析

机匣处理作为一种高效、经济的扩稳技术,越来越多的被用以提高压气机的稳定工作裕度。为了研究机匣处理对离心压气机多工况性能的影响,本文对3种进气回流机匣结构的压气机模型和无机匣处理的实壁压气机模型分别进行了数值仿真分析。数值计算结果与最优模型的试验结果吻合较好,比较准确的预测了喘振边界的位置,验证了计算方法的可靠性。结果表明,只有结构合理的进气回流机匣处理才能在各个转速下均显著扩大压气机小流量的稳定工作范围,其中机匣处理的开槽位置和前置导流挡板对其性能有着重要影响。     

Numerical study on the range enhancement of a centrifugal compressor with a ring groove system

A numerical study of casing treatments on a centrifugal compressor to improve stability and stall margin is presented. High efficiency, high pressure ratio, and a wide operating range are required for a high-performance centrifugal compressor. A ring groove casing treatment is effective for flow range enhancement in centrifugal compressors. Compressor performance was analyzed according to the ring groove location, and the results were compared with the case without a ring groove. The effect of guide vanes in the ring groove was also investigated. Four variants of grooves were modeled and simulated using computational fluid dynamics to optimize the groove location. Numerical analysis was performed using a commercial code ANSYS-CFX program. The simulation results showed that the ring groove increased the operating range of the compressor. The ring groove with guide vanes improved both performance of the compressor at low flow rates and the stall margin of the compressor.     

Stall inception and warning in a single-stage transonic axial compressor with axial skewed slot casing treatment

Characteristic changes in the stall inception in a single-stage transonic axial compressor with an axial skewed slot casing treatment were investigated experimentally. A rotating stall occurred intermittently in a compressor with an axial skewed slot, whereas spike-type rotating stalls occurred in the case of smooth casing. The axial skewed slot suppressed stall cell growth and increased the operating range. A mild surge, the frequency of which is the Helmholtz frequency of the compressor system, occurred with the rotating stall. The irregularity in the pressure signals at the slot bottom increased decreasing flow rate. An autocorrelation-based stall warning method was applied to the measured pressure signals. Results estimate and warn against the stall margin in a compressor with an axial skewed slot.     

压气机叶顶微喷气扩稳研究（英文）

The mechanism of compressor stall margin enhancement using the tip air injection is explored. The transonic compressor, NASA Rotor 37, is taken as the object to study the tip clearance flow under active control of tip air injection by numerical simulations. The effects of injection parameters(injection total temperature, injection position, injection angle, injection mass flow, injection port size, injection type and etc) on the stall margin extension are emphatically analyzed. Results show that the enhancement of tip leakage vortex enlarges the low-energy region induced by the shock wave in the row channel when the working condition is moving to stall point. In addition, the enhancement of radial vortex increases its entrainment ability, which tends to expand separation zone. Once the tip injection imposed, the decrease of the leakage vortex intensity widens the stall margin, while the total pressure loss increases to some extent due to the mixing of the tip micro jet with the mainstream. It is found that injection parameters should be restricted to a moderate region so as to achieve a good stall margin extension without an excessive increase in the pressure loss.     

自循环机匣处理喷气位置对压气机性能的影响

为了揭示自循环机匣处理对Stage 37气动性能的影响机理，利用数值模拟方法研究了不同喷气位置对压气机气动性能的影响。在设计转速时，分析了不同喷气位置的自循环机匣处理装置的叶尖流场，探讨了自循环机匣处理的扩稳机理。数值模拟结果显示：不同喷气位置的自循环机匣处理在略微降低压气机效率的情况下，能够分别扩大2.96%，2.72%，2.83%，2.6%的失速裕度；设计转速时，Stage 37中转子叶尖区激波/叶尖泄漏涡相互干涉以及泄漏涡破裂后产生的阻塞区，是影响Stage 37压气机内部流动失稳的关键因素。自循环机匣处理的扩稳机制主要在于利用高速喷气抑制叶尖泄漏涡的破碎程度，减小叶尖阻塞区面积，进而提高压气机的失速裕度。     

Inlet Recirculation Influence to the Flow Structure of Centrifugal Impeller

Inlet recirculation is proved as an effective way for centrifugal compressor surge margin extension,and is successively used in some engineering applications.Unfortunately its working mechanism is still not being well understood,which leads to redesigning of inlet recirculation mostly by experience.Also,most study about inlet recirculation is steady to date.It is necessary to study surge margin extension mechanism about inlet recirculation.To expose the mechanism in detail,steady and unsteady numerical simulations were performed on a centrifugal compressor with and without inlet recirculation.The results showed that,with inlet recirculation,the inlet axial velocity is augmented,relative Mach number around blade tip leading edge area is significantly reduced and so is the flow angle.As the flow angle decreased,the incidence angle reduced which greatly improves the flow field inside the impeller.Moreover,inlet recirculation changes the blade loading around blade tip and restrains the flow separation on the blade suction side at the leading edge area.The unsteady results of static pressure around blade surface,entropy at inlet crossflow section and vorticity distributions at near tip span surface indicated that,at near stall condition,strong fluctuation exists in the vicinity of tip area due to the interaction between tip leakage flow and core flow.By inlet recirculation these strong flow fluctuations are eliminated so the flow stability is greatly enhanced.All these improvements mentioned above are the reason for inlet recirculation delays compressor stall.This research reveals the surge margin extension reason of inlet recirculation from an unsteady flow viewpoint and provides important reference for inlet recirculation structure design.     

十级高压压气机气动方案设计的优化

对HARIKA程序进行改进,创新性地修正了效率模型并引入Koch失速静压升系数模型,采用E3十级高压压气机气动特性试验数据验证此改进HARIKA程序,结果表明改进HARIKA程序对压气机100%转速失速边界的预估精度达到了99%。采用NSGA-II多目标遗传算法进行气动方案设计优化,优化后的方案与初始方案相比设计点的总效率提高了3.4%,喘振裕度提高了6%;通过调节进口导叶和前五级静子叶片的安装角,使得优化方案在非设计转速下的特性也得到了提高。     

离心压气机机匣处理与导叶轮缘放气的扩稳机理分析及比较

采用数值模拟方法对导叶轮缘放气、进气回流及周向槽机匣处理扩大离心压气机稳定工作范围进行研究,并与实壁机匣离心压气机特性进行对比,分析三种处理方式扩大压气机稳定工作范围的机理。结果表明,导叶顶部吸力面分离流动和间隙泄漏流相互作用导致压气机失速。导叶轮缘放气将吸力面分离流动产生的低能流团吸除,减弱了顶部通道堵塞。进气回流给顶部进气添加负预旋,减小了顶部来流攻角,能抑制吸力面流动分离。周向槽机匣处理减弱了顶部间隙泄漏向叶轮进口的回流。三种处理方式都能减弱顶部通道堵塞、推迟压气机失速发生,而进气回流和导叶轮缘放气具有较大的扩稳能力。     

Numerical study on near-stall flow unsteadiness in an axial compressor with casing treatment

Time-accurate numerical calculations were performed to investigate unsteady flow features in a low-speed axial compressor. The test compressor has axial skewed slots over the rotor tip region as casing treatment to improve the stall margin. The calculated data are in good agreement with the measured data. This paper reports the effect of casing treatment and flow unsteadiness on the rotor near stall by examining the flows in the smooth wall and casing treatment cases. The axial skewed slot can remove the blockage induced by the tip clearance leakage flow by removing and injecting the flow near the tip. However, for the casing treatment case, blockage is induced near the hub because the hub-corner stall is caused by a decrease in the axial momentum in this region. The tip leakage flow has inherent unsteadiness in the smooth wall case caused by the relatively large tip clearance, whereas the hub-corner stall has unsteadiness in the casing treatment case. The two types of unsteadiness have functions in inducing stall inception. Furthermore, axial slots of different sizes were tested to examine the effect of slot geometry on rotor flow stability. The change in flow structure related to the stall inception was subject to flow injection through the recirculation in the slots.