Volute Chamber Research Articles

Transport of a Mixture of Sand and Water Through a Pump Characterized by Dual Inlets and a Double-Layered Impeller

A centrifugal pump incorporating two inlets and a double-layered impeller is proposed for transporting a mixture of sand and water. The double-layered impeller (primary impeller) encircles a secondary impeller. To reveal the operating and flow characteristics of such a pump, numerical work is conducted with a validated numerical method. The effects of the feed rate of sand and the rotational speed of the impeller are investigated. The results show that the pump efficiency is not monotonically related to the solid volume fraction. At a feed rate of sand of 2.10 m3/min and a rotational speed of 950 rpm, the lowest pump efficiency is reached. In the volute chamber, vortices of various sizes are evidenced. With increasing rotational speed, the overall solid volume fraction in the pump decreases. Meanwhile, when the solid volume fraction attains 0.28, sand particles tend to accumulate near the outer rim of the volute chamber. The axial force acting on the primary impeller increases with the rotational speed. Under different operating conditions, the radial forces point unanimously toward the third and fourth quadrants.

Research on the Internal Flow Characteristics of an Electric Coolant Pump

Abstract To investigate the internal flow characteristics of an automotive electronic coolant pump, numerical simulations were performed utilizing the ANSYS CFX commercial software suite. The study delved into the velocity distribution, pressure pulsation intensity characteristics, and entropy generation of the electronic coolant pump under varying operational conditions. The findings revealed that with an increase in the flow rate, the coolant flow velocity within the pump also escalated. Concurrently, the separation flow at the trailing edge of the blade diminished, while the flow velocity at the trailing edge of the pressure surface escalated. Notably, the impeller and volute emerged as the primary sites generating pressure pulsations, with pressure pulsation intensity within the pump surpassing that of the design condition in off-design scenarios. Furthermore, entropy generation predominantly manifested at the impeller, volute, and front pump chamber locations, with the impeller exhibiting minimal total entropy generation under design conditions. These insights serve as crucial reference points for optimizing the design of automotive electronic coolant pumps.

Numerical investigation of particle effect on wear characteristic of centrifugal slurry pump based on CFD-DEM coupling

PurposeIn the process of conveying the solid–liquid two-phase medium of the centrifugal slurry pump, the wear of the flow-passing parts is an important problem affecting its life and safe operation. Therefore, a numerical investigation on the wear characteristics of the centrifugal slurry pump under different particle conditions was conducted.Design/methodology/approachA solid-liquid two-phase model based on CFD-DEM coupling is established and used to analyze the flow field and the wear characteristics of the flow-passing parts with different particle densities, volume fractions and sizes.FindingsParticle conditions will affect the pump flow field. To analyze the pump wear characteristics, the wear distribution, wear value and cumulative force laws of flow-passing parts under different particle conditions are obtained. In each flow-passing part, with the increase of particle density, volume fraction and size, the wear area is concentrated and the wear depth increases. Under different particle conditions, the wear is mainly on the volute chamber and the blade pressure surface, and the tangential cumulative force of flow-passing parts is much larger than the normal cumulative force.Originality/valueAn accurate model and a coupled simulation method for predicting the wear of the slurry pump are obtained, and the wear characteristic law can provide a reference for the design of the slurry pump to reduce friction.

Numerical investigation of inlet section structure effect on wear characteristic of particle condition in centrifugal slurry pump by CFD-DEM coupling

To improve the wear resistance of the centrifugal slurry pump, the inlet structure is optimized, and an equal-diameter inlet section structure is designed. Considering the particle-particle and particle-wall interactions, a two-phase flow simulation model based on CFD-DEM (computational fluid dynamics-discrete element method) coupling is established under the sparse particle condition. The Archard wear model and Relative wear model are used for quantitative and qualitative wear analysis. The flow field and particle trajectory analysis are carried out under an equal-diameter inlet section structure and a different-diameter inlet section structure. The wear characteristics of the flow-passing parts are carried out. The results show that the simulation model has good accuracy. The error between the numerical simulation results and the experimental results is less than 5%. Under the equal-diameter inlet section structure, the overall wear of the slurry pump is reduced by 15%, the wear of the volute chamber is reduced by 17.5%, and the wear of the inlet section is reduced by 93.8%. The equal-diameter inlet section structure can reduce the turbulent intensity and make the flow field stable. And the equal-diameter inlet section structure helps to reduce the wear degree and wear area of the pump.

Study on Optimization of Pump Shaft Transmission System of Plastic Centrifugal Pump

At present, the design of the pump shaft transmission system mostly refers to the design method of the metal pump transmission system. The dynamic and static characteristics of the plastic centrifugal pump are not related to the structural parameters of the pump shaft. Aiming at the influence of the structural parameters of the pump shaft transmission system on the dynamic and static performance of the plastic centrifugal pump, the three-dimensional model of the impeller and volute chamber was drawn by Creo5.0. The CFD calculation of the load of the plastic centrifugal pump was carried out. The flow field of the plastic centrifugal pump under ideal working conditions was simulated by ANSYS FLUENT. Combined with the application principle of singular function in mechanics, the mathematical model of a deflection of the pump shaft transmission system was constructed. Considering the minimum deflection and the maximum critical speed of the first order as the objective function, an optimization model of the structural parameters of the pump transmission system was established. The NSGA-II multiobjective optimization method was used to solve the optimal structural parameters of the optimization model, and the optimization design of the pump shaft span, cantilever, front, and rear bearing clearance was completed. The optimal span cantilever ratio of the rotor model of the single span cantilever structure was 1:0.75. Compared with the traditional design model, the optimized pump shaft deflection is reduced by 52.35%, and the first-order critical speed is increased by 42.77%. Simultaneously, using polynomial fitting as a mathematical tool, the experimental data were analyzed, and the mathematical expression of the rotation speed deflection relationship of the pump shaft at the first critical rotation speed and the corresponding function curve was obtained.

Redesign of Centrifugal Pump with Capacity 286.8 M3/hrs and Head 32 Metre at Karawang International Industrial City

Mechanical equipment has an important role to support the needs of a process. There is mechanical equipment, namely a pump that functions to move liquid fluid from one place to another through the piping medium. Based on report from customer, Centrifugal pump ETA-N 150 x 125 - 315 which functions as supply distribution of clean water from Water Treatment Plant (WTP) to the Karawang area International Industrial City (KIIC) experienced a decrease in capacity and Head and happened unbalance on the pump drive motor rotor. After an investigation by the team engineering PT. TG Engineering, found problems such as heavy corrosion and corrosion erosion on surface impeller, spoons impeller and volute chamber, deep scratch and light corrosion on shaft / shaft, as well as malfunction bearing on bearing pump and bearing pump drive motor unbalance. Referring to the results of the investigation, the authors design and select centrifugal pump components based on the results of the investigation. So that after calculating the dimensions of impeller, shaft, key and component selection such as type bearing, lubrication bearing, as well as coupling.

Design and Analysis of Centrifugal Pump Using Computational Fluid Dynamics

Centrifugal pumps are used to transport drinks / fluids with rotational kinetic power conversion to hydro energy dynamics of fluid glide. The rotational electricity is normally derived from the engine or electric motor or turbine. In the simplest case is typical, the liquid enters the pump impeller along or close to the rotating axis and is accelerated through the impeller, flowing radially outward into a diffuser or volute chamber (casing), from in which he came. Contemporary blade impellers in centrifugal pumps used in commercial applications include aluminum or metallic. It is proposed to layout a centrifugal pump, using Computer Aided Design (CAD) software with a variety of metallic alloys and non-metallic composite materials, examine the electricity and deformation using simulation software program. In order to evaluate the effectiveness of Metal Alloys and non-steel composites. The purpose of this observe is to trade the fabric and perform unique analyzes which includes Static, dynamic, evaluation to find the first-rate substances to reduce weight and enhance efficiency the usage of SOLID WORKS software program (Premium Version 2014). It also involves a technique of manufacturing methods to recognise Blower use Non-metal composite fabric. Keywords: centrifugal pumps, Computer Aided Design (CAD), Metal Alloys, NonMetallic Composite Materials, SOLIDWORKS, Simulation Analysis

Study on the volute chamber shape of swirling shaft adopted in water diversion project

As an environment-friendly internal energy dissipation technology, the swirling shaft energy dissipation has been more and more applied. In this paper, the influence of the shape of the volute chamber on the flow pattern and energy dissipation rate is studied by the CFD numerical simulation method combined with the physical model test method. The results show that with the increasing of the diameter of the volute chamber, the diameter of the cavity in the volute chamber increases correspondingly, which effectively alleviates the backwater phenomenon on the upstream channel section of the shaft. Increasing the width of the inlet of the volute chamber can promote the flow pattern of the upstream channel section from the pressure flow to the non-pressure flow. The setting of the arc wedge rectification flip bucket can improve the inlet and inner flow pattern of the volute chamber.

Numerical Investigation of the Fluid Flow Characteristics in the Hub Plate Crown of a Centrifugal Pump

Due to the lack of understanding in the flow mechanism of the hub plate crown, the current calculation of the disc friction loss and the axial thrust in the centrifugal pump often uses empirical formulas. Research on the flow characteristics of the hub plate crown is of practical significance. The shroud and hub cavities are respectively studied with regard to tangential and radial velocities at the four different angular positions (0°, 90°, 180°, and 270°) at the four different operational points (0.6Qsp, 0.8Qsp, 1.0Qsp, and 1.2Qsp). Results indicate that at the same operational point, the smaller the volute chamber sectional area is, the higher the tangential velocity of the fluid core zone of the shroud cavity is. Radial leakage flow from the volute to the seal ring at the same operational point appears in 0° and 90° direction; when the flow is large, the tangential and radial velocities of the shroud and hub cavities with the same radius tend to be equal with axial symmetry. The axial leakage flow through the balance holes significantly affects the radial distribution of both tangential and radial velocities of fluid flow in the hub cavity. The numerical calculation results of fluid leakage through the clearance of back sealing ring are in good agreement with the test results. Accordingly, the magnitude of leakage is closely related to the fluid pressure and velocity distribution in the hub plate crown of the centrifugal pump. The analysis of the flow characteristics in the hub plate crown of the centrifugal pump could reveal the cause of the disc friction loss from the mechanism, providing a significant guidance for improving the accuracy of calculation and balancing the axial thrust in the centrifugal pump.

Research on pressure fluctuation characteristics of a centrifugal pump with guide vane

In order to study the pressure pulsation characteristics of a centrifugal pump with a guide vane, a pump with specific speed ns= 190 was chosen as the research object. The numerical simulation was carried out using the standard k-ε turbulence model. The pressure pulsation characteristic was researched at a set monitoring point. The reliability of the numerical simulation was verified with experiment results. The pressure pulsation characteristic curves of each calculation domain were obtained by dimensionless data processing. The results elucidate that the rotor/stator interaction at the outlet of the impeller is the main source for the pressure pulsation. With increasing distance, the pressure pulsation gradually decreases; the pressure pulsation amplitude of the pressure surface is larger than the suction surface; the pressure pulsation in the flow channel of the guide vane remains the same; the pressure fluctuation near the outlet of the annular volute chamber is larger, and the pressure pulsation near the upstream of the flow channel is quite complicated. The pressure pulsation at the annular volute and axial symmetry is the same.

CFD-modeling of processes in a high-pressure oxidizer pump for the turbopump assembly of a liquid rocket engine

The article presents CFD modeling of the work process in the oxidizer pump of a turbopump assemblyusing the ANSYS CFX software, as well as the comparison of numerical and theoretical calculations of theanalytical relations based on geometric data. Problems were encountered when modeling the flow of the pumpdue to inaccuracies in the drawing. The spherical radius in the area of the volute chamber throat had to bereduced, otherwise the model would not be topologically consistent with the original. The data on the vaneangles at the inlet and outlet of the centrifugal impeller were absent in the drawings. The blade angles weredetermined by the previously constructed geometric model. Negative pressure at the entrance of the impellervanes was found in the analysis of the first results of CFD-calculation. Increasing the number of elements in thispart of the calculation model made it possible to reduce the area of the negative pressure.CFD-modeling error with respect to the analytical solution does not exceed 11% by the parameters of total andstatic pressure. The results of the work can provide a visual representation of the processes taking place duringthe operation of the high-pressure pump of a turbopump assembly. The CFD-model can also be used for furtherresearch of work processes in liquid oxygen pumps to reduce the number of development tests.

Numerical Simulation of the Two-Phase Flow in a New Type Cyclone

A new type cyclone with oblique top, transitional volute chamber, eccentric inner cylinders and sloping outlet were designed and manufactured by numerical analysis, which had been applied to the five-stage preheater in the cement plant with the capacity of 5000t/d. To simulate the gas flow field and particle trajectory in cyclone, the Fluent software was used, and the RNG k-ε model and discrete random walk model were proposed. The flow characteristics of gas-solid two-phase were analyzed. It is found that the strongly swirling flow occurs in the new type cyclone, and the particles of raw meal can be more efficiently separated from the gas.

Theoretical and Experimental Studies of Hydraulic Characteristics of Discharge Tunnel with Vortex Drop

The velocities at given points in the volute chamber, the contracted section and the vertical dropshaft of a discharge tunnel with vortex drop were measured by a small specially designed L-shaped tube, as Laser Doppler Velocimetry (LDV) or Particle Image Velocimetry (PIV) would not work there due to the special structure of the discharge tunnel with vortex drop. Hydraulic empirical formulas were proposed to predict the velocities and the angles of the velocities made with the vertical direction θ. The theoretical analysis results were in good agreement with experimental data. Therefore, the method proposed in this paper can be used to analyze related characteristics of discharge tunnels with vortex drop. Additionally, different model scales were considered to predict the cavitation characteristics on the wall of a dropshaft in practical engineering.

Experimental Study of a New Hydrocyclone for Multi-Density Particles Separation

A new structure of hydrocyclone is designed to meet the demand of separating particles heavier or lighter than water simultaneously. Based on the conventional hydrocyclone, the structural modifications with a section in the middle and a volute chamber on the top of the hydrocyclone to accumulate the separated low density particles. Some factors that influence the separation efficiency of hydrocyclone were investigated in this paper. For the heavy phase, those influencing factors included the inlet flow rate and underflow split ratio. For the light one, different outlets for discharging the light phase were taken into account. The results show that there exists an optimum inlet flow rate for a series of underflow split ratios. The top outlet for separating light phase particles is better than the side outlet's.

Enhancement of Hydrocyclone Classification Efficiency for Fine Particles by Introducing a Volute Chamber with a Pre‐Sedimentation Function

AbstractA new hydrocyclone was designed with a volute chamber positioned prior to the inlet. Since the volute chamber prior to the inlet has a pre‐sedimentation function due to the centrifugal sedimentation effect, coarse particles are concentrated on the outer side and fine particles are concentrated on the inner side as the particles reach the entrance of the hydrocyclone. Consequently, coarse particles in the hydrocyclone are easily separated into the underflow and fine particles are easily transferred into the overflow. As a result, the separation or classification performance of the hydrocyclone was improved effectively. Compared with the traditional type of hydrocyclone, this new type of hydrocyclone with a volute chamber before the inlet was shown to possess a much higher classification efficiency for fine particles.

Seal‐less Centrifugal Blood Pump with Magnetically Suspended Rotor: Rot‐a‐Flot

Limitations of current centrifugal blood pumps are related to heat generation of bearings and leakage of seals, to dead water zones, and to poor efficiency. A new concept is proposed in this paper to ameliorate these problems based on a miniaturized magnetic drive, and a prototype is introduced. The pump rotor is suspended and driven by a radial permanent magnetic field that stabilizes the impeller in 4 of the 6 spatial degrees of freedom and allows it to be top-spun on a single blood-flushed pivot bearing with minimal load and friction. A shrouded impeller with an open center and 4 logarithmically curved channels is run inside a cone-and-plate-type housing with a spiral volute chamber. In vitro testing was performed comparing this design with the BioMedicus, St. Jude, and Sarns pumps. The prototype is demonstrated to have the smallest internal volume (35 ml), surface (190 qcm), and passage time (0.5 s at 4 L/min), as well as the highest hydraulic efficiency (up to 0.4) of all devices studied.

A flow visualization study of the NCVC centrifugal blood pump.

A compact centrifugal pump, NCVC-1, has an open-type impeller with 6 curved vanes, and it is characterized by no shaft and no seal. A tunnel is placed in the center of the impeller-rotor assembly to irrigate the back space behind the rotor. To evaluate the flow, we performed 3 visualization methods: tracer, oil film, and injection streak line method. The flow, observed by the tracer method in NCVC-1, indicated little turbulence along vanes. A volute chamber proved effective to reduce vortex formation in the outlet. Oil film pattern revealed no flow separation on vanes at 5 L/min. Washout flow behind the rotor is essential to prevent thrombus formation and was shown as inward spiral flow without any stagnation. These data suggested that a combination of visualization techniques was useful to analyze various flow conditions, and the NCVC-1 has excellent flow characteristics with little turbulence and little flow stagnation, which must be beneficial to low hemolysis and high antithrombogenicity.

Experience in the use of surfactants for preventing corrosion of hydromechanical equipment at the Ust'-Kamenogorsk hydroelectric power station

1. The use of a surfactant of the ABDM or OBDM type increases the bonding of paint-and-varnish materials to a wet metal surface and improves adhesion of the coatings; this increases the service life of the plant as a whole. 2. Applications of protective coatings on the inner surface of the volute chamber and penstock and investigations on experimental sectors of coatings have revealed the practical feasibility of corrosion protection of hydromechanical equipment.

Investigation of transients in reversible pumped-storage station hydraulic machines

Experimental investigations into the nature of transients occurring in a reversible hydraulic machine with loss of drive in pump operation and load shedding in turbine operation have demonstrated that, for reversible radial-axial hydraulic machines, pump operation is the determining factor as regards pressure increase in the volute chamber, and speed variation and load variations on the guide-vane equipment. The choice of minimum closure time of the guide-vane equipment is of great importance, from the standpoint of preventing the unit from approaching the counter-flow range. In order to prevent a substantial pressure increase in the volute chamber and pipeline in the second stage of the transient process either automatic delay in closure of the guide-vane equipment or free no-load water discharge from the volute chamber as the pressure rises above the permissible limit may be provided.

Variations of the Characteristics of the Centrifugal Pump and Flow Conditions at the Outlet of the Impeller due to the Difference of the Size of the Volute Chamber

Variations of the Characteristics of the Centrifugal Pump and Flow Conditions at the Outlet of the Impeller due to the Difference of the Size of the Volute Chamber