隔舌安放角对离心泵的水动力特性影响研究

为了研究螺旋形蜗壳内部流动规律以及不同隔舌安放角对离心泵内部流动特性的影响,基于ANSYSCFX14.5对5种不同隔舌安放角的离心泵模型进行了定常与非定常计算和数据分析,并对离心泵的水力特性进行了实验验证。分析结果表明,随着隔舌安放角的增大,离心泵的高效区明显加宽,但是设计工况附近的水力性能稍有下降,其中在大流量区域,隔舌安放角的作用比较明显;隔舌安放角的不同主要对非设计工况下离心泵内部流体流态影响较大,其中在小流量工况时,随着隔舌安放角的变小,叶轮各流道内的流体流态分布的对称性明显改善,在大流量工况下,随着蜗壳隔舌安放角的减小,蜗壳出口段垂直截面方向的速度梯度变大;隔舌安放角的不同对叶轮所受径向力的影响很小,不同隔舌安放角的离心泵所对应的径向力分布规律几乎一致。

Research on hydraulic characteristics of centrifugal pump with different volute tongue angle

In order to study the internal flow of the spiral case, and the unsteady flow characteristics of centrifugal pump with differently placed volute tongue angle, based on the ANSYS-CFX14.5, we carried out steady and unsteady calculation and data analysis aiming at five schemes of spiral volute of different tongue angle, and the hydraulic characteristics of the pump were verified by tests. The analysis results show that with the increase of tongue position angle, the efficient area of centrifugal pumps is extended, but the hydraulic performance under the design condition decline slightly, and the tongue angle has an important effect in large flow cases; in non-design case, different tongue angles greatly influence the internal fluid state, especially in the low flow conditions, with the decrease of tongue angle, the symmetry of the fluid flow distribution in the channel of the impeller is improved obviously, and in the large flow condition, the velocity gradient in the vertical cross-section of the volute outlet is greatly increased with the decrease of the tongue angle. It's also found that the variation of tongue angles has very little effect on the radial force of the impeller, the radial force distribution is almost the same regardless of the variation of tongue angel.