采用计算流体力学(computational fluid dynamic，CFD)方法建立了贯通式袋型阻尼密封(fully partitioned pocket damper seal，FPDS)三维数值模型，并研究密封齿数Nb、密封齿厚度b及主/副腔室长度比λ对密封动力与泄漏特性的影响。结果表明：FPDS有效阻尼Ceff与直接刚度K的频率依赖性较高，直接阻尼C与交叉刚度k的频率依赖性较低且随着涡动频率的增加而降低；有效阻尼Ceff随齿数、密封齿厚度的增加而增大，而主/副腔室长度比对Ceff影响相对较小，在研究工况范围内，Nb=12时Ceff最高，较原始模型平均提高约12.69%，密封齿厚度b=5.048 mm时有效阻尼Ceff为原始模型的111%~138%，当主/副腔室长度比λ=5.1时有效阻尼Ceff仅为原始模型95%~105%；FPDS泄漏量随密封齿数减小而急剧增加，且主/副腔室长度比λ存在最佳值(λ=1)使密封泄漏性能最优，而密封齿厚度对密封泄漏量影响较小。

A threedimensional numerical model of a fully partitioned pocket damper seal (FPDS) was established by using the computational fluid dynamics (CFD) method. The effects of tooth number Nb, tooth thickness b and length ratio λ of mainminor cavity on the dynamic and leakage characteristics of the FPDS were studied. The results show that the effective damping Ceff and direct stiffness K of FPDS are frequencydependent highly. The direct damping C and crosscoupled stiffness k have low frequency dependence and decrease with the increase of whirling frequency. The effective damping increases with the increase of tooth number and tooth thickness, while the effective damping is affected by the length ratio of mainminor cavity relatively slightly. Within the scope of the study condition, when tooth number is 12, the effective damping achieves the maximum value and increases by about 12.69% on average compared with the original model; and the effective damping of the FPDS is about 111% to 138% of the original model when the seal tooth thickness is 5.048 mm;the effective damping of the FPDS is only 95% to 105% of the original model when the length ratio of mainminor cavity is 5.1.The results also show that the leakage flowrate of the FPDS increases sharply with the decrease of the seal tooth number. There exists an optimum length ratio of mainminor cavity of 1 to obtain the best leakage performance. The tooth thickness has little effect on the leakage flowrate of the FPDS.

TK730.2

国家自然科学基金（51875361）;上海市自然科学基金（20ZR1439200）