Influence of Screw Centrifugal Inducer on Internal Flow Structure of Vortex Pump

2020 ◽  
Vol 142 (9) ◽  
Author(s):  
Hui Quan ◽  
Jing Cheng ◽  
Ying Guo ◽  
Lei Kang ◽  
Guoyi Peng
Keyword(s):  
Energy Conversion ◽  
Flow Structure ◽  
Axial Force ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Good Method ◽  
Power Capacity ◽  
Two Phase ◽  
Pump System ◽  
Vortex Pump

Abstract Installing an inducer upstream of the main impeller is an effective approach for improving the performances of a centrifugal pump. In order to study the influence of inducer on the internal flow characteristics and evolution of vortex pump, the numerical simulation and experimental test of the 150WX-200-20 vortex pump have been done by the principle of computational fluid dynamics, to acquire performance and internal flow structure change of the vortex pump with inducer and without inducer. Based on these, the energy conversion of vortex pump is combined with the changes of the through-flow and circulating-flow of the internal flow structure. Through analyzing the influence of inducer on it, the energy conversion characteristic of vortex pump is revealed. The results show that adding the inducer can guarantee the power capacity of the vortex pump and improve the anticavitation performance, so as to improve the pump head and flows. Equipped with suitable for transporting solid liquid two phase flow of the screw centrifugal inducer, it can effectively weaken the existence of circulating-flow and significantly improve the flow situation in the impeller field. Adding inducer can weaken axial force of vortex pump and enhance stability of pump. And under the condition of no clogging, the conclusions are of great significance for improving the power capacity and fluid energy conversion of the vortex pump. In addition, it is a good method to weaken the axial force of the pump and enhance the stability of the pump system by adding the inducer.

scholarly journals Influence of Blade Type on the Flow Structure of a Vortex Pump for Solid-Liquid Two-Phase Flow

Machines ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 353
Author(s):  
Hui Quan ◽  
Yanan Li ◽  
Lei Kang ◽  
Xinyang Yu ◽  
Kai Song ◽  
...  
Keyword(s):  
Flow Structure ◽  
Liquid Flow ◽  
Single Phase ◽  
Solid Phase ◽  
Internal Flow ◽  
Phase Flow ◽  
Centrifugal Pumps ◽  
Two Phase ◽  
Vortex Pump ◽  
Solid Liquid

Vortex pumps have good non-clogging performance owing to their impellers being retracted into retraction cavities, but they are much less efficient than ordinary centrifugal pumps. In this paper, numerical simulations were performed on a model of the 150WX200-20 vortex pump for four different blade types, and the influence of blade structure on pump performance was determined. The simulations revealed the existence of axial vortices in the flow passage between the blades in the impeller region. The geometric characteristics of these axial vortices were more regular in two-phase solid-liquid flow than single-phase liquid flow. The presence of the solid phase reduced the vortex strength compared with the single-phase flow and suppressed the increase in size of the secondary circulation vortex. It was found, however, that the blade shape had a greater influence on the circulating flow than the presence of the solid phase. The flow state of the medium flowing out of the impeller domain had a direct effect on the circulating flow with this effect being related to the law governing the flow of the medium in the flow channel between the blades. It was found that the performance of a front-bent blade was the best and that of a curved blade the worst. This influence of blade type on the internal flow structure was used to further explain the relationship between the internal flow structure and the external characteristics of the vortex pump, the understanding of which is crucial for blade selection and hydraulic optimization.

Study on Influence of Nozzle Structure on Flow in Diesel Nozzle Orifice

2012 ◽  
Vol 246-247 ◽  
pp. 127-130
Author(s):  
Bing Li ◽  
Xue Song Hu ◽  
Xiao Feng Cao ◽  
Gui Qi Jia ◽  
Fang Xi Xie ◽  
...  
Keyword(s):  
Flow Characteristics ◽  
Internal Flow ◽  
Key Factors ◽  
Complex Flow ◽  
Two Phase ◽  
Nozzle Orifice ◽  
Fuel Flow ◽  
Flow Features ◽  
Diesel Nozzle ◽  
Nozzle Hole

The fuel flow characteristics in diesel nozzle orifice are key factors to the atomization of fuel near the nozzle orifice. In the paper, two-phase flow model is used to simulate the complex flow features in nozzle orifice, and to study the influences of the relative position of nozzles orifice axis and nozzle axis, and inclination angle of nozzle hole on the internal flow feature.

Numerical Investigation of Positive Displacement Rotary Lobe Pump With Twisted Rotors

2014 ◽  
Author(s):  
Xiaojun Jiang ◽  
Yi Li ◽  
Zhaohui He ◽  
Cui Baoling ◽  
Wenlong Dong
Keyword(s):  
Flow Structure ◽  
Stokes Equations ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Dynamic Flow ◽  
Flow Fluctuation ◽  
Flow Field Characteristics ◽  
Lobe Pump ◽  
The Impact

The three-dimensional flow field characteristics are obtained by performing numerical simulation of flow in a lobe pump with twisted rotors. The relationship between the dynamic flow structure and the flow fluctuation is explored. Actually, the viscous incompressible Navier-Stokes equations are solved within an unsteady flow model. The dynamic mesh technique is applied to obtain the dynamic flow structure. By comparing the simulated results of straight rotor with those of twisted rotor, the effect of rotor shape on the flow fluctuation was revealed. Finally, the impact of the lobes number of rotors on flow pulsations is discussed. The results show that there is an intrinsic relationship between the flow fluctuation and the vortex in the lobe pump. The use of twisted rotors can effectively improve the internal flow characteristics of lobe pump and reduce flow fluctuation. With the increase of the number of lobes, the lobe pump output is more stable and capacity has been improved.

Development of Analysis Algorithm and Computational Methodology for the Evaluation of Non-Uniform Energy Conversion System Performance: Part I — Component Analysis Modules

2006 ◽  
Author(s):  
Casey Loughrin ◽  
Hyunjae Park ◽  
Robert Weber
Keyword(s):  
Energy Conversion ◽  
Thermal Performance ◽  
System Performance ◽  
Flow Characteristics ◽  
Heating System ◽  
Component Analysis ◽  
Connectivity Matrix ◽  
Two Phase ◽  
Energy Conversion Systems ◽  
The Individual

This paper examines the development of the individual component analysis modules applied to two selected energy conversion systems; a vapor-compression refrigeration system and a boiler heating system. The energy conversion components used in this work are the evaporator, condenser, expansion valve, mixing chamber, open feedwater heater, pipe, boiler, pump, and compressor. The developed component analysis modules are able to apply input data and specifications to estimate the corresponding thermal performance of the component. Upon investigation of the two case studies presented, it was found that the two-phase heat exchanging components such as the evaporator, condenser and boiler were the primary sources of the non-uniform system performance characteristics. As a consequence, a system connectivity matrix has been developed to evaluate the mass and energy flow characteristics of working fluids between components. The developed component analysis modules, in conjunction with the system connectivity matrix, were exclusively used to calculate the local and overall system thermal performance.

Effects of moisturized inflow on compressor performance and aerodynamic noise

2021 ◽  
Vol 263 (1) ◽  
pp. 5467-5474
Author(s):  
Changhong Sun ◽  
Yipeng Cao ◽  
Chen Liu
Keyword(s):  
Two Phase Flow ◽  
Flow Characteristics ◽  
Water Concentration ◽  
Internal Flow ◽  
Aerodynamic Noise ◽  
Outlet Temperature ◽  
Phase Flow ◽  
Two Phase ◽  
Flow Method ◽  
Compressor Performance

The effects of moisturized inflow on turbocharger compressor performance and aerodynamic noise were numerical analyzed in this paper. The gas-liquid two-phase flow method based on Euler-Lagrange model was firstly introduced. The influence of water concentration and water droplet diameter on compressor performance and internal flow characteristics at design speed were studied using the two-phase flow method. The compressor aerodynamic noise was also predicted at design condition under two different inflow conditions, including ideal inflow and moisturized inflow with 0.1% water concentration. The results indicate that moisturized inflow with an appropriate water concentration can reduce the outlet temperature of the compressor and improve the compressor performance, in which the water concentration is a dominant parameter. There is a phase transition process of water in the compressor with moisturized inflow, but moisturized inflow has little effects on the compressor internal flow characteristics. Moreover, the moisturized inflow also has influence on compressor aerodynamic noise.

scholarly journals A Comparative Study on Centrifugal Pump Designs and Two-Phase Flow Characteristic under Inlet Gas Entrainment Conditions

Energies ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 65 ◽  
Author(s):  
Qiaorui Si ◽  
Gérard Bois ◽  
Minquan Liao ◽  
Haoyang Zhang ◽  
Qianglei Cui ◽  
...  
Keyword(s):  
Pressure Pulsation ◽  
Two Phase Flow ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Phase Flow ◽  
Water Mixture ◽  
Centrifugal Pumps ◽  
Two Phase ◽  
Void Fractions

Capability for handling entrained gas is an important design consideration for centrifugal pumps used in petroleum, chemistry, nuclear applications. An experimental evaluation on their two phase performance is presented for two centrifugal pumps working under air-water mixture fluid conditions. The geometries of the two pumps are designed for the same flow rate and shut off head coefficient with the same impeller rotational speed. Overal pump performance and unsteady pressure pulsation information are obtained at different rotational speeds combined with various inlet air void fractions (α0) up to pump stop condition. As seen from the test results, pump 2 is able to deliver up to 10% two-phase mixtures before pump shut-off, whereas pump 1 is limited to 8%. In order to understand the physics of this flow phenomenon, a full three-dimensional unsteady Reynolds Average Navier-Stokes (3D-URANS) calculation using the Euler–Euler inhomogeneous method are carried out to study the two phase flow characteristics of the model pump after corresponding experimental verification. The internal flow characteristics inside the impeller and volute are physically described using the obtained air distribution, velocity streamline, vortex pattern and pressure pulsation results under different flow rates and inlet void fractions. Pump performances would deteriorate during pumping two-phase mixture fluid compared with single flow conditions due to the phase separating effect. Some physical explanation about performance improvements on handing maximum acceptable inlet two phase void fractions capability of centrifugal pumps are given.

Flow Characteristics of High-Efficient Axial Flow Pump System

2015 ◽  
Author(s):  
Chao Liu ◽  
Fan Yang ◽  
Yan Jin ◽  
Hua Yang
Keyword(s):  
Flow Characteristics ◽  
Axial Flow ◽  
Internal Flow ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Hydraulic Loss ◽  
Pump System ◽  
High Efficient ◽  
Axial Flow Pump ◽  
Flow Pump

Three-dimensional flow-fields in a high-efficient axial flow pump system were simulated by CFD to further study the internal flow characteristics. The internal flow patterns of the pump system were obtained at large, small and optimum operating conditions. The highest efficiency of pump system measured and calculated are 82.57% and 81% respectively at blade angle 0°. For the suction passage, the axial velocity distribution uniformity reach 97.51%, and the hydraulic loss is 0.039m, the pipe efficiency calculated is 98.5% at the optimum operating conditions. The maximum velocity is 1.429 m/s in the range of operating conditions, which meet the requirement of National standard. The performances predicted were compared with measurement results. It was found that the calculated results agree well with the measured results. The overall flow pattern of the pump system is uniform and smooth, and the hydraulic loss is very small which gives the excellent hydraulic performances of pump system.

Numerical Study on Flow Characteristics in a Stirring Vessel

2011 ◽  
Vol 130-134 ◽  
pp. 3050-3053
Author(s):  
Ru Quan Liang ◽  
Jun Hong Ji ◽  
Fu Sheng Yan ◽  
Ji Cheng He
Keyword(s):  
Flow Field ◽  
Numerical Study ◽  
Fluid Model ◽  
Rotational Velocity ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Experimental Result ◽  
Flow Rule ◽  
Two Phase ◽  
Impeller Type

In order to improve the desulphurization efficiency of KR mixing method in the process of molten iron refining, the method of CFD was used to analyze the flow field in a stirring vessel. The Fluent software was adopted to simulate and analyze the internal flow rule in a 3D stirring vessel with the method of multiple reference frame approach, and the corresponding models of Euler two-phase flow fluid model and standard k-ε turbulence model were used. By comparing with the experimental result, the influence of important parameters of agitator on internal flow field in the stirring vessel, such as rotational velocity, immersion depth and impeller type was discussed, and the flow structure was analyzed as well.

Research on the Effect of Impeller Reflux Balance Holes on Pressure and Axial Force of Centrifugal Pump

2014 ◽  
Author(s):  
Cao Weidong ◽  
Dai Xun ◽  
Hu Qixiang
Keyword(s):  
Pressure Distribution ◽  
Centrifugal Pump ◽  
Axial Force ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Force Balance ◽  
Pump Chamber ◽  
Cavitation Characteristic ◽  
Sealing Ring ◽  
Different Diameters

The size of impeller reflux holes for centrifugal pump has influence on the pressure distribution of front and rear shrouds and rear pump chamber, as well as energy characteristics of whole pump and axial force. Low specific-speed centrifugal pump with Q=12.5m3/h, H=60m, n=2950r/min was selected to be designed with eight axial reflux balance holes 4.5mm in diameter. The simulated Q-H curve and NPSH were in good agreement with experimental data, which illustrated that centrifugal pump with axial reflux balance holes was superior in the cavitation characteristic to that with traditional reflux balance holes; however, it appeared little difference in head and efficiency. Compared with experiment results, the error of pressure at monitoring points in rear pump chamber was within permission. The pressure in rear pump chamber at 0.6 times rated flow is 29.36% of pressure difference between outlet and inlet, which reduces to 29.10% at rated flow and 28.33% at 1.4 times rated flow. As the whole, the pressure distribution on front and rear shrouds from simulation results is not a standard parabola, and axial force decreased as flow rate increased. Radical reflux balance holes chosen to be 5.2mm and 5.9mm in diameter were further designed with other hydraulic parts unchanged. With structural grids adopted for total flow field, contrast numerical simulation on internal flow characteristics of reflux holes with different diameters was conducted based on momentum equations and standard turbulence model (κ-ε). It is found that axial force of pump with radical reflux balance holes 5.2mm and 5.9mm in diameter is significantly less than that with radical reflux balance holes 4.5mm in diameter, so are the head and efficiency. Better effect of axial force balance can be obtained as the ratio of area of reflux balance holes and area of sealing ring exceeds 6.

Unsteady flow characteristics of energy conversion in impeller of centrifugal pump as turbine

2021 ◽  
pp. 095440622110207
Author(s):  
Senchun Miao ◽  
Hongbiao Zhang ◽  
Jiawei Zhang ◽  
Xiaohui Wang ◽  
Fengxia Shi
Keyword(s):  
Unsteady Flow ◽  
Energy Conversion ◽  
Centrifugal Pump ◽  
Time Domain ◽  
Power Loss ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Input Power ◽  
Impeller Blade ◽  
The Time Domain

To study unsteady flow characteristics of energy conversion in impeller of centrifugal pump as turbine (PAT), the overall and sub-section methods are used to calculate the unsteady flow of the PAT under six working conditions. Through numerical calculations, the net input power of the impeller, the time domain change law of the fluid's work on the impeller, the time domain change law of power loss in the impeller, and the time domain change law of energy conversion in different regions of the impeller are analyzed. Results show that: the dynamic and static interference between the impeller blades and the tongue caused the fluctuation of energy conversion; with the increase of area between the head of the impeller blade and the opposite tongue, the power loss in the impeller decreases. And when the blade head completely deviates from the position of the tongue about 10°, the power loss in the impeller is minimized. The power output of the PAT at different flow rates is related to its internal flow conditions and the geometric structure of each region of the impeller. The above research results can provide guidance on how to operate the PAT impeller stably and efficiently.

Sign in / Sign up

Export Citation Format

Share Document