Nozzle Jet Deviation from Bucket Pitch Circle’s Effect on the Stability and Efficiency of Pelton Turbine
-
Published:2023-04-26
Issue:5
Volume:11
Page:1342
-
ISSN:2227-9717
-
Container-title:Processes
-
language:en
-
Short-container-title:Processes
Author:
Deng Huiming1, Song Ke2, Deng Fangxiong2, Huang Yu1, Luo Tao2, Zhou Yijin1, Qin Bei1, Zeng Yongzhong1, Yu Zhishun1, Pang Jiayang3ORCID, Liu Xiaobing1
Affiliation:
1. Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu 610039, China 2. CHN Energy Dadu River Geshizha Hydropower Development Co., Ltd., Danba 626300, China 3. College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
Abstract
During the operation of a Pelton turbine, the centerline of the nozzle jet may deviate from the bucket pitch circle due to the low installation and maintenance accuracy, which will reduce the operating efficiency and the stability of the turbine and even cause severe vibrations and damages. Based on the VOF (Volume of Fluid) two-phase flow model and the SST k-ω turbulence model, the flow characteristics of a Pelton turbine were simulated with the nozzle jet deviating from the bucket pitch circle. The pressure pulsation inside the bucket and the force distribution of the runner were obtained, the turbine oscillation and efficiency were measured before and after the jet deviation, and the effects of the radial and axial deviations on the stability and efficiency of the Pelton turbine were analyzed. The results show that both the radial and axial deviations of the jet cause a significant increase in the axial force and the pressure pulsation amplitude of the turbine; the radial and tangential forces on the runner are slightly reduced; the maximum axial force on the runner is increased by 4 times and 2 times, respectively, after the axial and radial deviations within the maximum value allowed by the industry standard; and the efficiency of the turbine is reduced by 0.4% and 0.3%, respectively. The maximum relative amplitude of pressure pulsation in the radial offset case appears in the center of the bucket blade, while the axial offset case causes uneven pressure distribution on both sides of the diverter blade, uneven force on the bucket blade of the runner, and fatigue damage. By comparing the operation of the runner under the two offset cases, we can find that the axial offset of the jet has a greater impact on the stability of the runner than the radial offset, and the unit is more prone to vibration, increasing the risk of the unit lifting.
Subject
Process Chemistry and Technology,Chemical Engineering (miscellaneous),Bioengineering
Reference29 articles.
1. Avellan, F., Dupont, P., Kvicinsky, S., Chapuis, L., Parkinson, E., and Vullioud, G. (1998, January 9–11). Flow Calculations in Pelton Turbines—Part 2: Free Surface Flows. Proceedings of the 19th IAHR Symposium on Hydraulic Machinery and Cavitation, Singapore. 2. Vessaz, C. (2015). Finite Particle Flow Simulation of Free Jet Deviation by Rotating Pelton Buckets. [Ph.D. Thesis, EPFL]. 3. Kvicinsky, S., Kueny, J.L., Avellan, F., and Parkinson, E. (2002, January 9–12). Experimental and Numerical Analysis of Free Surface Flows in a Rotating Bucket. Proceedings of the 21st IAHR Symposium on Hydraulic Machinery and Systems, Lausanne, Switzerland. 4. 3D CFD simulation of the runaway process of a Pelton turbine;You;Proc. Inst. Mech. Eng. Part A J. Power Energy,2016 5. Numerical investigation of the interaction between jet and bucket in a Pelton turbine;Santolin;Proc. Inst. Mech. Eng. Part A J. Power Energy,2009
|
|