Research Article Numerical Investigation of Pressure Fluctuation in Centrifugal Pump Volute Based on SAS Model and Experimental Validation Qiaorui Si, 1 Jianping Yuan, 1 Shouqi Yuan, 1 Wenjie Wang, 1 Lei Zhu, 1 and Gérard Bois 2 1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, ZhenJiang 212013, China 2 LML, UMR CNRS 8107, Arts et Metiers Paristech, 8 boulevard Louis XIV, 59046 Lille Cedex, France Correspondence should be addressed to Shouqi Yuan; shouqiy@ujs.edu.cn Received 29 November 2013; Revised 19 December 2013; Accepted 30 December 2013; Published 12 February 2014 Academic Editor: Leqin Wang Copyright © 2014 Qiaorui Si et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Tis paper presents an investigation of pressure fuctuation of a single-suction volute-type centrifugal pump, particularly volute casing, by using numerical and experimental methods. A new type of hybrid Reynolds-averaged Navier-Stokes/Large Eddy Simulation, referred to as the shear stress transport-scale-adaptive simulation (SAS) model, is employed to study the unsteady fow. Statistical analysis method is adopted to show the pressure fuctuation intensity distribution in the volute channel. A test rig for pressure pulsation measurement is built to validate the numerical simulation results using eight transient pressure sensors in the middle section of the volute wall. Results show that the SAS model can accurately predict the inner fow feld of centrifugal pumps. Radial force acting on the impeller presents a star distribution related to the blade number. Pressure fuctuation intensity is strongest near the tongue and shows irregular distribution in the pump casing. Pressure fuctuation is distributed symmetrically at the cross-section of the volute casing because the volute can eliminate the rotational movement of the liquid discharged from the impeller. Blade passing frequency and its multiples indicate the dominant frequency of the monitoring points within the volute, and the low-frequency pulsation, particularly in the shaf component, increases when it operates at of-design condition, particularly with a small fow rate. Te reason is that the vortex wave is enhanced at the of-design condition, which has an efect on the axle and is presented in the shaf component in the frequency domain. 1. Introduction Centrifugal pumps, as essential energy-conversion and fuid- transporting devices, have been widely used in industry, agriculture, ship propulsion, and daily life [1]. Owing to the rotor-stator interaction between the asymmetric structure of the volute and the high-speed rotating impeller as well as a highly viscous fuid, the operation of centrifugal pumps can generate instability and pressure pulsations, which may be detrimental to the integrity and performance of the pump and may result in component fatigue, excessive vibration, and noise. With the trend in increasing rotation speed and power, pressure fuctuation in centrifugal pumps has become an urgent concern [2, 3]. Numerous studies on unsteady fow have compared experimental and numerical results in centrifugal pumps [4, 5]. Generally, the volute of the centrifugal pump is one of the major parts because it is directly connected to the external space. It is always designed as an Archimedes spiral, which could result in better pump performance, that is, strongest collection of water out of the impeller. However, limited stud- ies have been conducted on pressure fuctuation of the inner fow in the volute. Furthermore, because the experimental method is time consuming and costly, investigation methods for complex fuid fow can be replaced or complemented by numerical simulation with the development of computational fuid dynamics (CFD). Today, most CFD simulations are conducted with traditional Reynolds-averaged Navier-Stokes (RANS) equations. Using RANS for many fows is not suitable because the turbulent part can be extremely large and have the same order as the mean. Examples are unsteady fow in general, particularly fows with large separation in centrifugal pumps. For this type of fows, using large eddy simulation (LES) is more appropriate. Numerous studies have been conducted on fow in rotating machinery based on the LES method [6–8]. However, the LES method remains too costly Hindawi Publishing Corporation Advances in Mechanical Engineering Volume 2014, Article ID 972081, 12 pages http://dx.doi.org/10.1155/2014/972081