EFFECTS OF MERIDIONAL SHAPE ON HYDRAULIC AND SUCTION PERFORMANCE OF A HIGH SPECIFIC SPEED CENTRIFUGAL PUMP

2018 ◽  
Author(s):  
Hyeon-Seok Shim ◽  
Kwang-Yong Kim
Keyword(s):  
Centrifugal Pump ◽  
Specific Speed ◽  
Meridional Shape ◽  
Suction Performance

Theory and application of two-dimension viscous hydraulic design of the ultra-low specific-speed centrifugal pump

2019 ◽  
Vol 234 (1) ◽  
pp. 58-71 ◽  
Author(s):  
Cong Wang ◽  
Yongxue Zhang ◽  
Hucan Hou ◽  
Zhiyi Yuan
Keyword(s):  
Boundary Layer ◽  
Centrifugal Pump ◽  
Diagnostic Model ◽  
Two Dimension ◽  
Cavitation Performance ◽  
Hydraulic Design ◽  
Displacement Thickness ◽  
Low Specific Speed ◽  
Specific Speed ◽  
Low Efficiency

Low efficiency and bad cavitation performance restrict the development of the ultra-low specific-speed centrifugal pump (ULSSCP). In this research, combined turbulent boundary layer theory with two-dimension design and two-dimension viscous hydraulic design method has been proposed to redesign a ULSSCP. Through the solution of the displacement thickness in the boundary layer, a less curved blade profile with a larger outlet angle was obtained. Then the hydraulic and cavitation performance of the reference pump and the designed pump were numerically studied. The comparison of performance of the reference pump calculated by the numerical and experimental results revealed a better agreement. Research shows that the average hydraulic efficiency and head of the designed pump improve by 2.9% and 3.3%, respectively. Besides, the designed pump has a better cavitation performance. Finally, through the internal flow analysis with entropy production diagnostic model, a 24.8% drop in head loss occurred in the designed pump.

Optimal hydraulic design of an ultra-low specific speed centrifugal pump based on the local entropy production theory

2019 ◽  
Vol 233 (6) ◽  
pp. 715-726 ◽  
Author(s):  
Hucan Hou ◽  
Yongxue Zhang ◽  
Xin Zhou ◽  
Zhitao Zuo ◽  
Haisheng Chen
Keyword(s):  
Entropy Production ◽  
Centrifugal Pump ◽  
Orthogonal Design ◽  
High Energy ◽  
Geometrical Parameters ◽  
Production Theory ◽  
Local Entropy ◽  
Hydraulic Design ◽  
Low Specific Speed ◽  
Specific Speed

The ultra-low specific speed centrifugal pump has been widely applied in aerospace engineering, metallurgy, and other industrial fields. However, its hydraulic design lacks specialized theory and method. Moreover, the impeller and volute are designed separately without considering their coupling effect. Therefore, the optimal design is proposed in this study based on the local entropy production theory. Four geometrical parameters are selected to establish orthogonal design schemes including blade outlet setting angle, wrapping angle volute inlet width, and throat area. Subsequently, a 3D steady flow with Reynolds stress turbulent model and energy equation model is numerically conducted and the entropy production is calculated by a user-defined function code. The range analysis is made to identify the optimal scheme indicating that the combination of local entropy production and orthogonal design is feasible on pump optimization. The optimal pump is visibly improved with an increase of 1.08% in efficiency. Entropy production is decreased by 16.75% and 6.03% in impeller and volute, respectively. High energy loss areas are captured and explained in terms of helical vortex and wall friction, and the turbulent and wall entropy production are respectively reduced by 3.82% and 14.34% for the total pump.

scholarly journals Optimal Design of Slit Impeller for Low Specific Speed Centrifugal Pump Based on Orthogonal Test

2021 ◽  
Vol 9 (2) ◽  
pp. 121
Author(s):  
Yang Yang ◽  
Ling Zhou ◽  
Hongtao Zhou ◽  
Wanning Lv ◽  
Jian Wang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Centrifugal Pump ◽  
Large Scale ◽  
Internal Flow ◽  
Orthogonal Test ◽  
Centrifugal Pumps ◽  
Initial Model ◽  
Low Specific Speed ◽  
Specific Speed ◽  
Four Levels

Marine centrifugal pumps are mostly used on board ship, for transferring liquid from one point to another. Based on the combination of orthogonal testing and numerical simulation, this paper optimizes the structure of a drainage trough for a typical low-specific speed centrifugal pump, determines the priority of the various geometric factors of the drainage trough on the pump performance, and obtains the optimal impeller drainage trough scheme. The influence of drainage tank structure on the internal flow of a low-specific speed centrifugal pump is also analyzed. First, based on the experimental validation of the initial model, it is determined that the numerical simulation method used in this paper is highly accurate in predicting the performance of low-specific speed centrifugal pumps. Secondly, based on the three factors and four levels of the impeller drainage trough in the orthogonal test, the orthogonal test plan is determined and the orthogonal test results are analyzed. This work found that slit diameter and slit width have a large impact on the performance of low-specific speed centrifugal pumps, while long and short vane lap lengths have less impact. Finally, we compared the internal flow distribution between the initial model and the optimized model, and found that the slit structure could effectively reduce the pressure difference between the suction side and the pressure side of the blade. By weakening the large-scale vortex in the flow path and reducing the hydraulic losses, the drainage trough impellers obtained based on orthogonal tests can significantly improve the hydraulic efficiency of low-specific speed centrifugal pumps.

The effect of front streamline wrapping angle variation in a super-low specific speed centrifugal pump

2018 ◽  
Vol 232 (23) ◽  
pp. 4301-4311 ◽  
Author(s):  
Dong Liang ◽  
Zhao Yuqi ◽  
Liu Houlin ◽  
Dai Cui ◽  
Gradov D Vladimirovich ◽  
...  
Keyword(s):  
Centrifugal Pump ◽  
Pressure Pulsation ◽  
Energy Performance ◽  
Sweep Angle ◽  
Angle Variation ◽  
Noise Characteristics ◽  
Ansys Cfx ◽  
Low Specific Speed ◽  
Specific Speed ◽  
Element Method

In this research, super-low specific speed centrifugal pump ( ns = 25, Chinese units: ns = 3.6 nQ1/2/ H3/4) is studied. The effect of the front streamline wrapping angles variation (135°, 139° and 145°) of the turbine on energy performance is considered. The pressure pulsation, interior and exterior noise characteristics and the performance of the impeller are thoroughly evaluated both experimentally and numerically. The pump has been modeled by means of computational fluid dynamics code of commercial software ANSYS CFX 11.0 to estimate energy performance and pressure pulsation. Boundary element method and finite element method are used to investigate the interior and exterior noise characteristics of the centrifugal pump by varying the front sweep angle. The front sweep angle variation was found to have insignificant influence on centrifugal pump performance characteristics. However, it influences fluid hydrodynamics around the volute tongue. In addition, the decreasing of the front streamline sweep angle slightly reduces the sound pressure level for the exterior acoustics, but the radiation distribution of the acoustic field does not change. In its turn, the modified trailing edge of the blades can reduce the peak value of the superposition decreasing the pressure pulsations at the blade passing frequency and its harmonic frequencies.

The influence of blade outlet angle on the performance of centrifugal pump with high specific speed

Vacuum ◽  
2019 ◽  
Vol 159 ◽  
pp. 239-246 ◽  
Author(s):  
Hongchang Ding ◽  
Zikang Li ◽  
Xiaobin Gong ◽  
Maoshun Li
Keyword(s):  
Centrifugal Pump ◽  
Outlet Angle ◽  
Specific Speed

scholarly journals ANALISA PERHITUNGAN DAYA POMPA SENTRIFUGAL DI GEDUNG UNIVERSITAS 17AGUSTUS 1945 JAKARTA

2019 ◽  
Vol 4 (1) ◽  
pp. 7-14
Author(s):  
M Fajri Hidayat ◽  
Nor Fajri
Keyword(s):  
Pump Power ◽  
Centrifugal Pump ◽  
Water Requirement ◽  
Clean Water ◽  
Pump Head ◽  
Pump Shaft ◽  
Specific Speed

AbstrakPompa adalah suatu alat atau mesin untuk memindahkan cairan dari satu tempat ketempat lain melalui suatu media perpipaan dengan cara menambahkan energi pada cairan yang dipindahkan dan berlangsung secara terus menerus. Pompa yang digunakan dalam analisa ini yaitu Pompa Sentrifugal yang terdapat di gedung Universitas 17 Agustus 1945 Jakarta. Tujuan dari analisa ini yaitu untuk mengetahui kebutuhan air pada gedung Universitas 17 Agustus 1945 Jakarta. Kebutuhan air pada gedung Universitas 17 Agustus 1945 Jakarta dihitung berdasarkan luas lantai gedung dan pemakaian setiap dosen, karyawan, mahasiswa, dan rektorat di Universitas 17 Agustus 1945 Jakarta. Hasil analisa di dapatkan total kebutuhan air bersih pada gedung Universitas 17 Agustus 1945 Jakarta adalah 1.7910 Liter/hari. Kapasitas pompa sebesar 0.06 m3/s. Head total pompa sebesar 31.99 m. Putaran poros pompa yaitu 1500 rpm. Daya pompa sebesar 0.817 kW. Kecepatan spesifik sebesar 48.51 rpm. Dari hasil analisa dapat dinyatakan bahwa Pompa Sentrifugal yang berada di gedung Universitas 17 Agustus 1945 Jakarta sudah layak untuk digunakan. Kata Kunci : Kebutuhan air, kapasitas pompa, pompa sentrifugal Abstract          A pump is a device or a machine to move liquids from one place to another via a piping medium by adding energy to the fluid that is moved and continuous. The pump used in this analysis is the Centrifugal Pump contained in the building University 17 August 1945 Jakarta. The purpose of this analysis is to determine the needs of water in the building University 17 August 1945 Jakarta. Water requirement at University building August 17, 1945 Jakarta is calculated based on building floor and usage of every lecturer, staff, student, and rectorate in University 17 August 1945 Jakarta. The result of the analysis in obtaining the total clean water requirement at the building University 17 August 1945 Jakarta is 1.7910 Liter / day. The pump capacity is 0.06 m3 / s. The total pump head is 31.99 m. The rotation of the pump shaft is 1500 rpm. The pump power is 0.817 kW. Specific speed of 48.51 rpm. The results of the analysis can be stated that the Centrifugal Pump located in the building University 17 August 1945 Jakarta is feasible to use. Keywords : Water requirement, pump capacity, centrifugal pump

Effects of short blades on performance and inner flow characteristics of a low-specific-speed centrifugal pump

2017 ◽  
Vol 231 (4) ◽  
pp. 290-302 ◽  
Author(s):  
Can Kang ◽  
Ning Mao ◽  
Chen Pan ◽  
Yang Zhu ◽  
Bing Li
Keyword(s):  
Centrifugal Pump ◽  
Flow Rate ◽  
Pressure Fluctuations ◽  
Flow Characteristics ◽  
Low Flow ◽  
Back Surface ◽  
Flow Rates ◽  
Pump Operation ◽  
Low Specific Speed ◽  
Specific Speed

A low-specific-speed centrifugal pump equipped with long and short blades is studied. Emphasis is placed on the pump performance and inner flow characteristics at low flow rates. Each short blade is intentionally shifted towards the back surface of the neighboring long blade, and the outlet parts of the short blades are uniformly shortened. Unsteady numerical simulation is conducted to disclose inner flow patterns associated with the modified design. Thereby, a comparison is enabled between the two schemes featured by different short blades. Both practical operation data and numerical results support that the deviation and cutting of the short blades can eliminate the positive slope of pump head curve at low flow rates. Therefore, the modification of short blades improves the pump operation stability. Due to the shortening of the outlet parts of the short blades, velocity distributions between impeller outlet and radial diffuser inlet exhibit explicitly altered circumferential flow periodicity. Pressure fluctuations in the radial diffuser are complex in terms of diversified periodicity and amplitudes. Flow rate influences pressure fluctuations in the radial diffuser considerably. As flow rate decreases, the regularity of the orbit of hydraulic loads exerted upon the impeller collapses while hydraulic loads exerted upon the short blades remain circumferentially periodic.

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