基于流固耦合的离心泵口环间隙泄漏对叶轮强度的影响

发布时间：2019-03-13 18:26

【摘要】：基于流固耦合方法,以DG-350型多级离心泵次级叶轮为研究对象,研究了口环间隙泄漏对水泵次级叶轮变形和强度的影响。通过单向流固耦合分析和双向流固耦合分析得到了叶轮的等效应力和变形分布图,并对结果进行了对比分析。结果表明,在考虑间隙泄漏时,叶轮的最大总变形幅度为0.021 4 mm,最大等效应力为21.51 MPa。在不考虑间隙泄漏时,叶轮的最大总变形幅度为0.053 6 mm,最大等效应力为87 MPa。口环间隙的存在使得叶轮与导叶间的间隙流体产生较大的压力并作用于叶轮的前后盖板,从而抵消了一部分叶轮内腔的流体压力,减小了叶轮的变形幅度和应力集中。在叶轮最大变形和等效应力的最大集中区域附近随机选择A、B节点,通过瞬态分析,在最后1个旋转周期内,节点A、B处的等效应力随时间呈周期性变化。节点B处的等效应力始终大于节点A处,并且接近于最大等效应力,说明节点B附近的区域为应力集中的高发区。而节点A处的等效应力虽低于节点B处,但应力的变化幅度高于节点B处,说明节点A处更容易发生疲劳破坏。
[Abstract]:Based on the fluid-solid coupling method, the influence of clearance leakage on the deformation and strength of secondary impeller of DG- 350 multi-stage centrifugal pump is studied. The distributions of equivalent stress and deformation of the impeller are obtained by unidirectional fluid-solid coupling analysis and bi-directional fluid-solid coupling analysis, and the results are compared and analyzed. The results show that when the clearance leakage is considered, the maximum total deformation amplitude of the impeller is 0.021 4 mm, and the maximum equivalent stress is 21.51 MPa.. When the clearance leakage is not considered, the maximum total deformation amplitude of the impeller is 0.053 6 mm, and the maximum equivalent stress is 87 MPa.. The existence of gap between impeller and guide vane makes the clearance fluid between impeller and guide vane produce greater pressure and act on the front and back cover plate of impeller, thus canceling the fluid pressure in part of impeller cavity and reducing the deformation amplitude and stress concentration of impeller. The nodes A and B are randomly selected near the maximum concentration region of the maximum deformation and equivalent stress of the impeller. Through transient analysis, the equivalent stresses at nodes A and B change periodically with time during the last rotation period. The equivalent stress at node B is always greater than that at node A and is close to the maximum equivalent stress, indicating that the area near node B is a high incidence area of stress concentration. The equivalent stress at node A is lower than that at node B, but the range of stress change is higher than that at node B. this indicates that node A is more prone to fatigue failure.
【作者单位】：山东科技大学机电学院;
【基金】：山东省高等学校科技计划项目(J11LD21) 青岛市科技计划基础研究项目(12-1-4-6-(2)-jch)
【分类号】：TH311

【相似文献】