Effect of Impeller Trimming on Centrifugal Pump
Keywords:Centrifugal Pump, Impeller Trimming, Affinity Law, Pump Efficiency
AbstractPumps, especially centrifugal pumps, play an important role in engineering application, such as petroleum and petro-chemical industries, agricultural industries, portland cement industries etc. To obtain the best performance of the pumps, one has to operate the pumps at their design conditions. In some circumstances, however, the pumps must operate lower than their design conditions and result in the decrease in their performances. In such cases, it is possible to replace the pump impeller with the smaller impeller diameter or to cut its original impeller to smaller size as necessary. The cut of the impeller, or it is frequently referred to as impeller trimming, in some extence is preferable than replacing with new impeller or even by replacing with new pump with smaller head and capacity. In this study, we examine the effect of the pump impeller trimming to the pump performaces. The study was performed in the Fluid Mechanics Laboratory, Mechanical Engineering Department of ITS, Surabaya. The pump impellers were cut up to approximately 19 percent of its original pump impeller diameter, where the original pump impeller diameter is 129 mm. The pump has the maximum capacity of 100 liters/min and the total head of 31.5 m. The pump is powered by a 300 Watt electrical motor. Parameters to be studied in this research include pump capacity, pump head, pump power, and pump efficiency. The results of this study show that all data are in good agreement with the pump affinity laws. Pump capacity, pump head, and pump power decresase as the pump impeller diameter decreases. The pump efficiency is, however, in some extent, increases as the pump impeller diameter decreases. The maximum increase in pump efficiency is obtained when the ratio between the trimmed impeller to its original pump impeller diameter is approximately 89 percent (i.e. D2/D1 = 0.89), with the increase in pump efficiency of approximately 20 percent.
US DEPARTMENT OF ENERGY (US DOE), â€œOffice of Industrial Technologies. Variable Speed Pumping â€“ A Guide to Successful Applicationsâ€, Executive Summary, 2004.
EVANS, JOE, â€œPump Efficiency â€“ What is efficiency?â€, https://www.pumpsandsystems.com/pump-efficiency-what-efficiency, accessed on November 16, 2020.
BERLI, P. K., NIKO, P., BAMBANG, R., â€œEkstraksi Parameter Statistik Domain Waktu dan Domain Frekuensi untuk Mendeteksi Kavitasi pada Pompa Sentrifugal Berbasis Principal Component Analysis (PCA)â€, Rekayasa Mesin, v. 10, n. 2, pp. 165 â€“ 179, 2019.
BUREAU OF ENERGY EFFICIENCY, â€œPumps and Pumping Systemâ€, https://www.beeindia.gov.in/sites/default/files/3Ch6.pdf, pp. 113-134, accessed on October 04, 2021.
US DEPARTMENT OF ENERGY (US DOE), â€œTrim or Replace Impellers on Oversized Pumpsâ€, Energy Tips â€“ Pumping Systems, Pumping Systems Tip Sheet #7, Sep. 2006.
SAVAR, M., KOZMAR, HRVOJE, AND SULTOVIC, IGOR, â€Improving Centrifugal Pump Efficiency by Impeller Trimmingâ€, Desalination, v. 249, pp. 654â€“659, 2009.
WANG KAI, ZIXU ZHANG, LINGLIN JIANG, HOULIN LIU, AND YU LI, â€œEffects of impeller trim on performance of two-stage self-priming centrifugal pumpâ€, Advances in Mechanical Engineering, v. 9, n. 2 , pp. 1-11, 2017.
BAI YUXING, FANYU KONG, BIN XIA, FEI ZHAO, AND YINGYING LIU, â€œEffects of Impeller Diameter on High-Speed Rescue Pumpâ€, Hindawi: Mathematical Problems in Engineering, 2017, Article ID 1387210, pp. 15, 2017.
MATLAKALA, M E, D V V KALLON, K E MOGAPI, I M MABELANE, D M MAKGOPA, â€œInfluence of Impeller Diameter on the Performance of Centrifugal pumpsâ€, Conference of the South African Advanced Materials Initiative (CoSAAMI 2019), IOP Conf. Series: Materials Science and Engineering, 655, 2019.
LI, WENGUANG, â€Impeller Trimming of an Industrial Centrifugal Viscous Oil Pumpâ€, Int J Advanced Design and Manufacturing Technology, v. 5, n.1, pp. 1-10, 2011.
KHOEINI DAVOOD AND MOHAMMAD REZA TAVAKOLI, â€œFlow Characteristics of a Centrifugal Pump with Different Impeller Trimming Methodsâ€, FME Transactions, v. 46, pp. 463-468, 2018.
ZHOU, P., TANG, J. MOU, J., ZHU, B., â€œEffect of impeller trimming on performanceâ€, World Pumps, pp. 38â€“41, September, 2016.
ARUN SHANKAR V. K., SUBRAMANIAM, U., SHANMUGAM, P., HANIGOVSZKI, N., â€œA comprehensive review on energy efficiency enhancement initiatives in centrifugal pumping systemâ€, Applied Energy, v. 181, pp. 495-513, 2016.
AUGUSTYN T., â€œEnergy efficiency and savings in pumping systems â€” The Holistic Approachâ€. In: 2012 Southern African Energy Efficiency Convention, IEEE, pp. 1â€“7, 2012.
YANG, F., ZHAO, H., LIU, C., â€œImprovement of the Efficiency of the Axial-Flow Pump at Part Loads due to Installing Outlet Guide Vanes Mechanismâ€, Hindawi: Mathematical Problems in Engineering, 2016, Article ID 6375314, pp. 10, 2016.
SHU KERAN, XIAOMING YU, BIN ZHANG, FEI XIE, XIAOHUI TAO, MIANSHUN ZHU, HAIRONG MAO, â€œThe effect of impeller cut on the performance of middle specific speed centrifugal pumpâ€, IOP Conf. Series: Materials Science and Engineering, pp. 394, 2018.
BS (BRITISH STANDARD) EN ISO 9906-2012, Rotodynamic pumps â€“ Hydraulic performance acceptance test â€“ Grades 1, 2, and 3, 2012.
KETHAGUROV, M., Marine Auxilary Machinery and System, Peace Publisher, Moscow, 1965.
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