动力气体密封

介绍了一种实用、新型的密封方法－动力气体密封,即通过往密封部件内部送入压缩气体,使其内部压力高于外界压力,从而防止外界质进入密封部件内部以达到密封的目的,较好地解决了生产中的泄漏问题。     

径向迷宫密封泄漏速率计算方法的分析

对现有径向迷宫密封漏速率计算方法的理论论导出原理，公式特点，使用方法及其适用特性进行了综合论述，可供有关设计人员参考。     

迷宫密封泄漏量设计计算综述

本文分别阐述了Ｅｇｌｉ、ｋｅｄｒｔｏｎ、Ｓｏｍｅｒｌｉｎｇ和ｓｔｏｄｏｌａ等五种泄漏量的计算方法。     

粉体介质密封装置的设计改进

含固体颗粒介质的密封装置，常常因固体颗粒进入密封装置引起密封表面破坏。对填料密封设计进行改进，采用填料与迷宫组合密封结构，加气体保护密封方案，允许少量气体高速进入容器内，阻止固体颗粒进入密封腔内，保护密封表面免受破坏，改进设计的密封装置保护气体进入量可以根据固体颗粒大小及状态调节，以达到最经济的操作工况，且运行稳定。     

一种嵌入式迷宫密封装置

介绍了一种结构新颖、密封可靠的嵌入式迷宫密封装置,该装置既能防止冷却液掺入,双能阻止润滑油外漏。     

密封装置微小气体泄漏流量测量方法

在差压法测量气体流量的基础上,提出一种新的基于恒压恒容积差压法的微小泄漏流量测量方法,为消除系统误差,该方法使气流入口的压力在测量前后保持不变,从而可实现航空发动机密封件微小气体泄漏流量高精度测量,且流量越小测量误差越小。介绍微小气体泄漏流量测量方法的测量原理、高精度温度传感器、压力传感器、数据采集卡的选择,并通过试验验证恒压恒容积差压法测量微小泄漏流量的可行性。     

两种新型液压密封装置的设计

设计了两种新型的密封装置，一种是外压补偿式，一种是内涨补偿式。两种装置大大减少了液压油内、外泄漏的机会，使密封更加可靠，且相应提高了使用寿命。     

罗茨鼓风机气体密封套的选择

介绍了罗茨鼓风机三种气体密封套，并对其在生产实际使用时的密封效果作了比较，从而改进和完善了设备零部件的结构。     

迷宫密封泄漏量计算方法的分析

对现有的几种迷宫密封泄漏量计算方法的理论推导原理、公式特点、使用方法与适用范围等进行了分析,并提出了一种简化分析的迭代计算方法。对比迭代计算结果与文献中的实验结果后发现,该法对于亚临界工况和临界工况均十分有效,且适用于直通型、阶梯型和交错型等多种类型的迷宫密封,且较其它各种计算方法精度高,适用范围较广,有很好的通用性。     

径向迷宫密封泄漏特性的数值预报

基于迷宫密封内部流场的数值模拟,提出了一种径向迷宫密封泄漏特性的数值预报模型,并对一种径向锯齿型迷宫密封的泄漏特性进行了实例预报,预报结果与实验结果吻合较好.     

Experimental and Numerical Assessment of an Advanced Labyrinth Seal

A previously validated finite difference computer model for seal leakage was used in developing an advanced seal with reduced leakage. A new design feature is an annular groove judiciously located in the stator housing. A detailed assessment of this preliminary groove configuration was conducted, both experimentally and computationally. It was found that the presence of the particular groove considered here contributes an approximately 20 percent decrease in leakage, while introducing no shaft speed effects. To enhance physical insight, detailed computed distributions of streamlines are included. Further, the interesting measured effect of the relative axial position of the rotor/stator sealing surfaces on leakage rate and stator wall axial pressure distribution is examined.     

锯齿型径向迷宫密封机理研究

采用模型实验和数值模拟的方法，对锯齿型径向迷宫密封的密封机理进行了研究，结果表明，节流间隙中的射流偏转和流束收缩，可以有效地降低间隙的实际通流面积，提高密封性能，从而可以用节流间隙中的射流偏转来取代微小的节流间隙，实现在较大的节流间隙下的良好密封。     

活塞式制冷压缩机活塞与汽缸间隙迷宫密封的理论研究

对活塞式制冷压缩机工作过程进行了数值模拟,建立了活塞与汽缸迷宫密封的数学模型,分析了泄漏量随活塞与汽缸间隙及迷宫槽间距变化的关系.     

螺旋密封气吞及密封失效机理分析

本从泵的角度对螺旋密封“气吞”及“密封失效”现象作出了合理,全面的解释,并提出一种新型组合螺旋密封,分析结果表明,转速较高时,迷宫螺旋密封优于组合螺旋密封,优于单一结构螺旋密封,具有一定的工程使用价值。     

迷宫密封性能影响因素分析

影响迷宫密封性能的重要因素有许多，如结构型式、涡流空腔、节流间隙、齿数、齿倾角、压力、温度、转速和流向等，本文在综合国内外有关文献的基础上，对此进行了较全面详尽的分析与评述。     

Effect of Rub-Groove Wall Angle on the Leakage of Abradable Stepped Labyrinth Seals

Rub grooves are generally formed in gas-turbine labyrinth seals of the abradable type during various transients. The rub-groove shape, often the slope angle of the groove downstream wall, varies and largely depends on the rotordynamics and the thermal expansion rates of the rotor and the stator. The effect of rub-groove shape on stepped labyrinth seal leakage was studied by varying the slope angle of the groove downstream wall, using various tooth axial positions and various prerub radial clearances. The investigation was done for compressible flow, with air as the working fluid. A finite volume method was used to solve the two-dimensional axisymmetric, Reynolds-averaged Navier-Stokes equation system. The high-Reynolds-number k-? turbulence model was used along with wall functions. It was found that the wall angle of rub groove has a significant effect on the leakage as well as on the flow pattern. For the cases considered here, when the seal operates with the tooth positioned axially within the rub-groove axial width, the leakage decreases with an increase of the rub-groove downstream wall slope angle. However, for operation when the tooth lies axially just downstream of the groove, the leakage is slightly increased with an increase of the rub-groove wall angle. For cases with a certain tooth axial position and prerub radial clearance, a small change of groove sloping wall angle results in a large change in flow pattern.     

梳齿密封流动参数传递分析模型

针对梳齿密封流动参数随齿数增多计算量非线性增大的问题,提出流动参数传递分析模型.以单个齿或腔为分析的基本单元,由计算或试验数据得出参考点,用径向基神经网络建立单元前后断面的传递关系.按连续性条件沿流动方向将所有单元串联,从入口递推至出口,施加出口边界条件对各断面上流动参数迭代求解.以某梳齿密封为例,在双控制体模型数据基础上建立单元映射关系,进而组成传递模型,求解各腔内流动参数.结果表明新模型用较少的配置点就能精确得出各腔内流动参数,迭代方法收敛.该模型中一个单元的分析模型适用于同类单元,不需重复建模,可有效减少计算量.单元模型参考点可选用多种数据,易于扩展.     

迷宫空腔特性的耗散函数表示法

对于迷宫侬空的动能耗散特性，传统上用动能载越系数来表示。本文用流体力学中的耗散函数来表示，更能从物理上直观地反映迷宫空腔的耗散特性。并具体结构直通型和交错型迷宫；从理论上和实际上分析了这种表示法的可行性和可靠性。     

CFD Study on Stepped and Drum Balance Labyrinth Seal

The stability of rotors in turbomachines is affected by the labyrinth seal where driving forces are generated. Recent research results have shown that the preswirl has a significant influence on the rotordynamic characteristics of the straight labyrinth seal including both tooth-on-stator and tooth-on-rotor configurations. However, modern turbomachines require higher and higher pressure drop for the seal so that the eye seal is usually designed as stepped labyrinth, whereas the balance drum usually employs a tooth-interlocking labyrinth and a larger number of teeth. Both designs could generate greater forces on the rotor than the straight labyrinth seal. Therefore, it is necessary to further study the influence of preswirl on stepped and tooth-interlocking labyrinth seals. This article employed 3D calculational fluid dynamics (CFD) to solve the flow in those seals. Then the rotordynamic coefficients of the two seals at different preswirl rates were calculated based on the CFD results. The results were compared with test data and bulk flow results. A rotor stability analysis was conducted considering the balance drum seal with the coefficients predicted by the numerical method.