Static Characteristics of Annular Damper Seals With Square-Hole Pattern Stators in Turbulent Regime

方孔定子环形阻尼密封件在湍流状态下的静态特性

• 批准号: 17560117
• 负责人: KANEKO Satoru
• 金额: $ 2.3万
• 依托单位: Nagaoka University of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17560117/
• 关键词: Annular damper seals; Square-hole pattern; Annular plain seals; Leakage flow rate; Liquid-film pressure distributions; Pressure loss at steps; Dynamic fluid force; Dynamic coefficients; 円周方向溝付きシール; 乱流; 混合距離モデル

For improving the efficiency and the stability margin of pumps, various seal configurations have been proposed. The previous experimental results confirmed that damper seals with intentionally different stator roughness surface pattern would yield smaller cross-coupled stiffness coefficients, larger main damping coefficients and a lower leakage flow rate than conventional annular plain seals with smooth surfaces. In the present study, the theoretical and experimental investigations of the static and dynamic characteristics are carried on the annular damper seals with square-hole pattern stators. Averaged Navier-Stokes equation with turbulent coefficients and continuity equation are applied to the theoretical investigation, which are numerically solved in consideration of the pressure loss due to the flow passage across each step of square holes. The turbulent coefficients are calculated based on the "law of the wall" and Prandtl's mixing length hypothesis.The results are summarized as … More follows:(1) The numerical results of the static characteristics, i.e., the leakage flow rate and the pressure distributions in the seal clearance obtained only by the rotor spinning motion at the seal center are good agreement with the measured results, which verifies the validity of theoretical analysis.(2) The numerical results of the dynamic characteristics, i.e., the dynamic fluid force and the dynamic coefficients obtained by both spinning and whirling motions of the rotor, qualitatively agree with the measured results. In particular, the quantitative agreement of the main damping coefficients is obtained between the numerical and measured results.(3) The pressure loss at the steps in the circumferential direction influences mainly the tangential dynamic fluid force and increases the main damping coefficients, whereas the pressure loss at the steps in the axial direction decreases the leakage flow rate. These facts contribute to the design for the annular seals with the optimum configurations yielding better seal characteristics. Less

为了提高泵的效率和稳定裕度，已经提出了各种密封结构。先前的实验结果证实，阻尼器密封与故意不同的定子粗糙表面图案将产生较小的交叉耦合刚度系数，较大的主阻尼系数和较低的泄漏流量比传统的环形平面密封与光滑表面。本文对具有方孔结构的环形阻尼密封的静、动态特性进行了理论和实验研究。理论研究采用带湍流系数的平均Navier-Stokes方程和连续性方程，并考虑了每一步方孔通道的压力损失。根据壁面定律和普朗特混合长度假设计算了湍流系数，结果如下： ...更多信息 （1）计算结果表明，仅由转子在密封中心处的旋转运动得到的密封间隙内的泄漏流量和压力分布与实测结果吻合较好，验证了理论分析的正确性。(2)给出了动态特性的数值计算结果，由转子的旋转运动和涡动运动得到的动流体力和动系数定性地与测量结果一致。特别是，主要阻尼系数的定量协议之间的数值和测量结果。(3)周向台阶处的压力损失主要影响切向动态流体力并增加主要阻尼系数，而轴向台阶处的压力损失减小泄漏流量。这些事实有助于设计具有最佳结构的环形密封，从而获得更好的密封特性。少