Sediment erosion characteristics of large-flow and high-power centrifugal pumps
The Guangdong Water Resources Allocation Project around Beibu Gulf integrates a large-flow,high-power centrifugal pump system.This project is part of the national water resources comprehensive plan and is among the 150 major water conservancy projects aimed at addressing the water shortage in western Guangdong,particularly in the Leizhou Peninsula.The centrifugal pump used in this project operates under prolonged sandy conditions,which causes significant and unpredictable erosion issues.This study analyzes the erosion characteristics caused by sediment-laden water within the centrifugal pump.Sediment parameters,including particle mass concentration and size,were determined based on data collected from the West River.The solid-liquid two-phase flow within the centrifugal pump was investigated using the Euler-Lagrange method.The Oka erosion model was employed to predict the erosion characteristics of the pump's flow-through components.Numerical simulations were conducted to understand the head conditions on the erosion patterns and impact of various sediment parameters within the pump.Sediment parameters,such as particle mass concentration levels and sizes,were selected based on the typical conditions found in the West River.The influence of different operational head conditions on the pump's erosion characteristics and simulating conditions that varied from the design head to the lowest and highest head conditions was also examined.The results revealed that under typical sediment conditions,the pressure distribution within the centrifugal pump showed no significant difference between sediment-laden and clean water conditions,while low-mass concentration sediment had minimal impact on the internal flow field of the pump.However,operating the pump outside the design head condition resulted in a substantial increase in both the erosion area and intensity.Specifically,the erosion intensity at the lowest head condition was approximately three times higher than that under the design head condition.Sediment mass concentration primarily affected the erosion intensity,while sediment particle size influenced the distribution of the severely worn areas.With increasing sediment mass concentration,the erosion area and intensity on the impeller front cover increased,but the location of the severely worn area did not change significantly.Conversely,with increasing sediment particle size,the erosion area on the impeller front cover decreased,but the location of the severely worn area shifted noticeably.The study's simulations showed that larger particles tend to move towards the pressure side of the impeller blades,causing more significant erosion in those regions.This study demonstrated that sediment mass concentration and particle size are critical factors influencing the erosion characteristics of centrifugal pumps.The findings provide valuable insights into the erosion mechanisms within such pumps,offering guidance for their operation and maintenance under sandy conditions.The results indicate that to minimize erosion and enhance pump longevity,careful consideration of sediment parameters and operational head conditions is essential.By understanding the effects of these parameters,operators can optimize pump performance and reduce maintenance costs.This research contributes to optimizing pump design and operation,ensuring more reliable and efficient performance in sediment-laden environments.Future studies could further explore the development of erosion-resistant materials and coatings to enhance the durability of centrifugal pumps used in similar settings.
centrifugal pumphead conditionsediment mass concentrationsediment sizeerosion characteristics
万方数据
维普
