Pump Design Research Articles

Internal flow field changes and cavitation characteristics research of the high-pressure axial plunger pump

High pressure axial piston pumps have the characteristics of high power density, small volume and high integration degree and are used in coal machinery, construction machinery and other industrial fields. However, the cavitation impact of the oil flow field inside the pump directly affects the performance and stability of the plunger pump. Once the fault occurs, it will cause the equipment to stop, threatening the life of the current personnel. Taking the axial piston pump as the research object, this paper conducts a numerical simulation analysis of part of the basin model in the piston pump, discusses the fluid characteristics and cavitation mechanism in the piston pump, and provides a theoretical reference for the design and application of high pressure pumps.

Numerical investigation on slip velocity characteristics of gas-liquid two-phase flow in a multiphase pump under different blade tip clearance

Abstract It is significant to explore the slip velocity characteristics of two-phase in blade tip clearance (BTC) of multiphase pump for improving semi-open mixed-flow pump performance. On the ground of the Euler-Euler inhomogeneous model, a gas-liquid mixed-flow pump was taken as the research object. Using CFX software to simulate the flow field in the multiphase pump with conditions of the inlet gas void fraction (IGVF) are 10%, 20% and 30%. The slip velocity characteristics of gas-liquid two-phase in mixed-flow multiphase pump with different blade tip clearance sizes (BTCS) were analyzed. The results show that there is obvious slip velocity on blade leading edge (L.E.), trailing edge (T.E.) and pressure side (PS) of BTC of mixed-flow pump impeller. When BTCS is small, the slip velocity on the tip pressure side has little change along flow direction, but with the increase of BTCS, slip velocity on the tip pressure side will gradually increase. There is a positive correlation between slip velocity and the pressure gradient. The research results can provide significant guidance for optimization design of semi-open mixed-flow multiphase pump.

Numerical Study on the Hysteresis Effect of Volute Pump with Stay Vanes Based on Vortex Dynamics

Abstract The hysteresis effect of volute pump with stay vanes in the hump zone can aggravate the vibration and jumping of the units, which seriously threatens the unit’s safety and stable operation. The formation mechanism of the hysteresis effect in hump zone is analyzed by carrying out unsteady numerical simulation of the volute pump with stay vanes at medium-low specific speed based on vortex dynamics theory. The results show that hysteresis effect occurs in volute pump, the fluid inertia force in FID is smaller than that in FDD, and the fluid viscous force in FID is larger than that in FDD. The hysteresis effect is not only related to the Karman vortex generated by the flow separation of vane and guide vane, but also closely related to the stall vortex generated in the volute. This work may provide a guide way for the optimal design and stable operation of the volute pump with stay vanes.

Validation of the steady and unsteady simulation based on an axial-flow pump

Abstract An axial-flow pump offers high flow rates and efficiency with low power consumption, making it ideal for applications that require transferring the large volume of fluid. Applying the numerical simulation in predicting hydraulic performance, analyzing the phenomena, and optimizing the design of the axial flow pump is very cost-effective and flexible. This study is performed to clarify the difference between steady and unsteady simulations based on the axial flow pump. Numerical simulations are carried out using the steady and unsteady Reynolds-averaged Navier-Stokes (RANS and URANS) equations and a shear stress transport reattachment modification turbulence model with small y+ values at all wall surfaces. To show the accuracy, numerical simulations are analyzed and compared with testing results. The difference in steady and unsteady simulations is presented by a detailed analysis of the flow field under the deep stall condition. The result shows that the numerical and testing results are in good agreement with each other. However, the unsteady results are more accurate than the steady results, especially in the saddle zone. Under deep stall condition, it is difficult to accurately predict the hydraulic performance and fluid flow characteristics inside the axial flow pump through steady simulation because of the time-dependent flow.

Numerical Investigation on internal flow characteristics of a mixed-flow pump with Tandem malposed blades

Abstract Mixed-flow pump plays an important role in national major projects and national economic construction. In this paper, a mixed-flow pump is taken as the research object, and the internal flow characteristics and the distribution of turbulent kinetic energy in the pump under different malposed angles of blade are studied by using numerical simulation and blade modification method. The results show that the pump efficiency and head are higher when the tandem blade angles (α) are 15° and 45°, and the pump head is the largest at the α =15°, increasing by 4.37%. Meanwhile, the high-pressure area inside the impeller was large, which had a higher pressurization performance. Under the rated flow condition, the velocity curve of α =15° changes most gently, which is close to the prototype velocity curve, and the single hump zone is not obvious. The tandem malposed blades can restrain the velocity fluctuation and improve the flow field in the impeller. At α =45°, the turbulent kinetic energy dissipation and the velocity fluctuation were the smallest; the flow field was the most stable. The research results have reference significance for the optimal design and selection of mixed flow pump.

The influence of the gap width of the blade on the performance of the mixing pump

Abstract The spiral axial flow gas-liquid mixed pump has some problems, such as unsteady flow and sharp decline in performance, when it runs in the biased condition with high gas content. Based on the principle of fluid flow and the design concept of slot drainage, a slit blade is proposed in this study to improve the degree of gas-liquid separation inside the mixing pump. The slit connects the pressure surface of the blade of the mixing pump with the suction surface. The pressure difference between the pressure surface and the suction surface leads to the generation of slit jet, which plays a “blowing” role in the adhesion of the gas phase on the suction surface inside the mixing pump. And make the stagnant air mass in the flow passage move again, so as to slow down the gas-liquid separation in the mixed transport pump. This study provides theoretical reference for the design and optimization of spiral axial flow gas-liquid mixed pump.

Modeling load sensing pressure and flow control of axial piston pump by analyzing impact of bulk modulus

This research is focused on investigating the impact of the bulk modulus on the dynamics of variable delivery hydraulic axial piston pump (VAPP). The bulk modulus decreases exponentially with an increase in temperature whereas there is a linear positive relationship with pressure. The research revealed that there is a 6% (1 litre/s) increase in flow rate and a 2.6% (1.5 MPa) decrease in delivery pressure with a 38.75% (0.434 GPa) decrease in bulk modulus. Flow ripple and pressure pulsation are reduced by 39.3% and 43.2% respectively with a corresponding 38.75% decrease in bulk modulus. Pressure pulsation and flow ripple are responsible for the generation of noise and vibrations in the system. Flow rate increase contributes to better response and control of the VAPP. While a reduction in bulk modulus offers improved dynamic performance and overall response of the VAPP, it is noteworthy that a decrease in bulk modulus hurts the pump delivery pressure. The research allows the pump designer to formulate a strategy to optimize the bulk modulus under dynamic operating conditions to achieve optimal pump performance.

Analysis of the velocity non-uniformity in waterjet inlet duct

Abstract Since the waterjet propulsion unique advantages, it’s applied more widely. But the Inlet duct and other structures prone to particular flows. Since the inlet duct of a special structure, the velocity distribution shows non-uniformity, departing from the waterjet pump design scenarios. In this paper, waterjet pump is simulated to study its velocity non-uniform of inlet duct and to investigate the discipline of the velocity distribution. By changing the inlet boundary conditions, the corresponding velocity field is obtained, to analyze the results under different conditions. It is researched the effect of inlet duct velocity non-uniformity on waterjet propulsion system.

Fault diagnosis of axial piston pump based on multi-source subdomain adaptation and sensor data fusion

The axial piston pump is the core component in hydraulic systems. Its condition monitoring and fault diagnosis are crucial to ensure the safe and reliable operation of hydraulic systems. However, most of the existing fault diagnosis methods for axial piston pumps use the same working condition data. In actual operation, axial piston pump often experience varying loads, and the collected data is typically correlated but has different distributions. Therefore, a transfer learning method of multi-source subdomain adaptation and sensor fusion (MSASF) is proposed for fault diagnosis of axial piston pump. The proposed MSASF has three modules, a shared feature extraction module, a domain-specific feature extraction module and an output decision module. Firstly, the adaptive weighted fusion of multi-sensor data features is realized by the shared feature extraction module and the common features of multi-source heterogeneous data are extracted. Secondly, in the domain-specific feature extraction module, multi-branch network is used to extract features of each pair of source and target domains and the local maximum mean difference is utilized to align the sub-domain distribution of each pair of source and target domains. Finally, in the output decision module, the distribution distance between each pair of source domain and target domain is calculated using maximum mean discrepancy to obtain its weighted score. Combined with the classification output of each source domain, the final diagnosis decision is made. A dataset was constructed for the axial piston pump design fault experiment, and four sets of transfer tasks were designed to compare with those of seven classic methods. The experimental results showed that the proposed MSASF method exhibits a superior domain adaptation effect and fault diagnosis performance.

Influence of structural parameters of distributor disk on flow pulsation in axial piston pumps

Firstly, a virtual prototype of axial piston pump AMESim is used to observe the effects of outlet pressure, swashplate inclination, bulk modulus (compressibility), density, dynamic viscosity, air viscosity, air content, dead space volume, leakage of mating clearance of the moving parts, plunger cylinder clearance, eccentricity, contact length of the copper bushing of the high-pressure piston pump, and the over-flow area of the flow distributing disk on the swashplate torque, the pressure in the plunger chamber, the pulsation in the flow rate, and the backing-up. To explore the influence of fluid noise, mechanical noise and air noise. After comparison, the overflow area of the disk, which has the greatest influence on the noise, is selected as the research object, in which the structural parameters of the disk are the most important influencing factors. Finally, it is found that too large or too small overflow area will aggravate the fluid noise and mechanical noise of the piston pump. Therefore, the optimized design of the structure of piston pump flow distribution plate is of great significance to reduce the vibration and noise of the hydraulic system. This study catches the optimization method of axial piston pump flow distribution shock, which can provide a reference for the design and optimization of axial piston pumps.

Innovative claw rotor design for claw vacuum pump and its power consumption analysis

The claw vacuum pump is extensively utilized in semiconductor, photovoltaic and aerospace industries because of its dry oil-free and compact structure. In order to reduce the power consumption of the claw vacuum pump caused by its special mixing process during operation, a novel pair of claw rotors was proposed. This innovation involves replacing the conventional circular arc at the dedendum of the claw rotors with an eccentric circular arc. A geometric model of the novel claw rotor was established, and the geometric characteristics of both the novel and conventional claw rotors were compared. Subsequently, the optimal design parameters were determined. The pressure distribution and power consumption of two claw vacuum pumps were analyzed with numerical simulations. Study results indicates that the power consumption of the proposed claw vacuum pump in the mixing process is reduced by 72.3 %, and the total power consumption is reduced by 12.6 % compared to the conventional pump. The study is of great significance for reducing power consumption of the claw vacuum pumps and improving application.

Optimization of Microfluidics for Point-of-Care Blood Sensing.

Blood tests are widely used in modern medicine to diagnose certain illnesses and evaluate the overall health of a patient. To enable testing in resource-limited areas, there has been increasing interest in point-of-care (PoC) testing devices. To process blood samples, liquid mixing with active pumps is usually required, making PoC blood testing expensive and bulky. We explored the possibility of processing approximately 2 μL of whole blood for image flow cytometry using capillary structures that allowed test times of a few minutes without active pumps. Capillary pump structures with five different pillar shapes were simulated using Ansys Fluent to determine which resulted in the fastest whole blood uptake. The simulation results showed a strong influence of the capillary pump pillar shape on the chip filling time. Long and thin structures with a high aspect ratio exhibited faster filling times. Microfluidic chips using the simulated pump design with the most efficient blood uptake were fabricated with polydimethylsiloxane (PDMS) and polyethylene oxide (PEO). The chip filling times were tested with 2 μL of both water and whole blood, resulting in uptake times of 24 s for water and 111 s for blood. The simulated blood plasma results deviated from the experimental filling times by about 35% without accounting for any cell-induced effects. By comparing the flow speed induced by different pump pillar geometries, this study offers insights for the design and optimization of passive microfluidic devices for inhomogenous liquids such as whole blood in sensing applications.

Impacts of activation energy and electroosmosis on peristaltic motion of micropolar Newtonian nanofluid inside a microchannel

This study investigates the impact of electroosmosis on the peristaltic flow of unsteady micropolar nanofluid with heat transfer. The findings could enhance the design of peristaltic pumps, potentially improving drug delivery systems, simulations of blood flow in medical devices, and cancer treatments. The fluid under investigation adheres to a micropolar model and flows through a microchannel that exhibits peristalsis along its walls. Moreover, the system is subjected to various external effects, including a uniform magnetic field, the electroosmotic phenomenon, heat absorption, and a chemical reaction with activation energy. Consequently, the problem is mathematically modulated by a system of nonlinear partial differential equations governing the velocity, temperature, and nanoparticle concentration. By employing wave transformation, these governing equations are reduced to ordinary differential equations (ODEs). The reduced equations were solved both analytically, using the homotopy perturbation method, and numerically, using the Runge–Kutta–Merson method. A comparison was made between the solutions, which were found to be closely aligned. Furthermore, a series of figures were employed to provide visual representation and discussion of the implications of the physical properties. The calculations reveal that the electroosmotic flow (EOF) enhances the axial flow of the micropolar fluid along the direction of the applied electric field. It is also observed that the increase in the activation energy (which indicates a low reaction rate) increases the concentration profile whereas the increase in the reaction rate parameter reduces the concentration profile. Additionally, the spin velocity of the particles is diminished by either an increase in the magnetic parameter or the coupling parameter.

Design and optimization of heat pump with infrared drying for Glycyrrhiza uralensis (Licorice) processing.

A new dryer, integrating infrared and heat pump drying technologies, was designed to enhance licorice processing standardization, aiming at improved drying efficiency and product quality. Numerical simulation using COMSOL software validated the air distribution model through prototype data comparison. To address uneven air distribution, a spoiler was strategically placed based on CFD simulation to optimize its size and position using the velocity deviation ratio and non-uniformity coefficient as indices. Post-optimization, the average velocity deviation ratio decreased from 0.5124 to 0.2565%, and the non-uniformity coefficient dropped from 0.5913 to 0.3152, achieving a more uniform flow field in the drying chamber. Testing the optimized dryer on licorice demonstrated significant improvements in flow field uniformity, reducing licorice drying time by 23.8%. Additionally, optimized drying enhanced licorice color (higher L* value) and increased retention rates of total phenol, total flavone, and vitamin C. This research holds substantial importance for advancing licorice primary processing, fostering efficiency, and improving product quality.

Performance prediction and optimization strategy for LNG multistage centrifugal pump based on PSO-LSSVR surrogate model

The Multistage LNG cryogenic submersible pump is one of the crucial power equipment in LNG transport process. However, the high hydraulic losses and low efficiency of this pump make it necessary to optimize the structure of its impeller in order to reduce energy losses. In this study, an optimization strategy based on particle swarm optimization (PSO) and least squares support vector regression (LSSVR) machine is proposed to optimize the structure of impeller. The optimization of the impeller structure with the PSO-LSSVR method increased the head and efficiency of the LNG cryogenic submersible pump by 0.57% and 2.72%, respectively. Comparing the calculation results of PSO-LSSVR method with the CFD results, we found that the relative error between them don’t exceed 3%, which verified the calculation accuracy of the method. Then, an enstrophy dissipation theory is introduced to quantitatively analyze the pump energy loss. Comparing the impellers before and after optimization revealed that the maximum reduction in impeller energy loss was 18%.. The distribution and mechanism of vortex generation inside the impeller were analyzed with the Q-criterion and the relative vortex transport equation. The relative vortex transport equation revealed that the horseshoe vortex structure at the leading edge of the optimized impeller blade was suppressed, and the relative vortex stretching term and the Coriolis force term, which dominate the evolution of the vortex structure, were reduced. This study will provide related reference for the optimal design of Multistage LNG cryogenic submersible pumps.

Satellite Thermal Management Pump Impeller Design and Optimization

This study presents a numerical approach to the design and optimization of centrifugal impellers used in the pumps of active thermal control systems of spacecraft. Although launch costs have shrunk in the last decade, the performance requirements, such as efficiency and reliability, have increased, as such systems are required to work up to 15 years, depending on the mission. To that effect, our paper deals with the first step in this pump design, namely the hydraulic optimization of the impeller. Constructively, this type of impeller allows for certain balancing systems and labyrinth seals to be applied in a more effective way, as well as allowing for additive manufacturing methods to be used—however, details regarding these aspects are beyond the scope of the current paper. By combining empirical formulas, computational fluid dynamics (CFD) analysis, and artificial neural networks (ANNs), the research focuses on achieving high efficiency and fast manufacturing. A series of geometries have been sized and validated using steady-state RANS (Reynolds Averaged Navier-Stokes) simulations, leading to the identification of the most efficient configuration. Subsequent optimization using an ANN resulted in a refined impeller design with notable improvements in hydraulic performance: a 3.55% increase in efficiency and a 7.9% increase in head. Key parameters influencing impeller performance, including blade number, incidence, and backsweep angles, are identified. This approach offers a comprehensive method to address the evolving requirements of space missions and contributes to the advancement of centrifugal pump technology in the space domain.

Magnetocaloric refrigerator with magnetic pump and liquid metals

One-seventh of the worldwide electricity is used for refrigeration related activities. When compared to the predominantly used vapor compression refrigeration system, magnetocaloric refrigeration provides an energy-efficient and eco-friendly alternative. It utilizes a magnetocaloric material which undergoes temperature changes when exposed to magnetic field changes. Nearly 60% of the total system cost is due to the permanent magnets used. For a given cooling power, the amount of permanent magnet needed is determined by the residence time required by the heat transfer fluid in each cycle. The start-of-the-art systems utilizes water-alcohol mixture as the heat transfer fluid, and a mechanical pump for its circulation. By utilizing non-toxic and non-hazardous gallium-indium-tin based liquid metals as heat transfer fluid, which has three order of magnitude higher thermal diffusivity, the residence time and the permanent magnetic material is reduced nearly by a factor of 10. Even accounting for the cost of the liquid metal, it results in considerable savings in the system cost. We present experimental results on the entropy change of using liquid metal with (Mn,Fe)2(P,Si)-based magnetocaloric material, and numerical results on the system level analysis. Further, to improve the reliability of the system, we propose to use magnetic pumping for heat transfer fluid circulation, which does not have any moving parts. The state-of-the art magnetic pump works at frequencies in the range of 100 to 1000 Hz. However, they cause detrimental heating effects due to eddy current losses. To overcome this, we have designed a pump that operates at 1 Hz and still achieves comparable flow rates. We present numerical results on the pump design by studying the dynamics of ferrofluid rise in a vertical pipe with multiple electromagnetic coils.

Design of 10 L/s liquid hydrogen pump with integrated inducer and centrifugal impeller

With the global focus on energy and environmental issues, hydrogen energy development has become more and more important. The liquid hydrogen centrifugal pump is an important equipment for hydrogen transportation. In this paper, we designed an integrated impeller and the space guide vane used in 10L/s hydrogen pump. The integrated impeller which is closed structure combined of an inducer and an centrifugal impeller shows better performance than traditional Semi-open impeller. We optimized the structure of the pump and finally obtained the performance curves. This results provide a guidance for the manufacture of the liquid hydrogen pump, and also provide a reference for the design and manufacture of other liquid hydrogen pumps.

Next-Gen Medical Technology a Smart Approach to Syringe Injection Pump Automation

This presents the design, implementation, and successful validation of a cutting-edge IoT-based Syringe Injection Pump (SIP) for precision medication administration. In response to the increasing demand for enhanced healthcare automation, this system leverages technologies to address critical challenges in medication delivery. This SIP incorporates a robust Internet of Things (IoT) framework, enabling seamless communication between the device and a central healthcare management system. The automated syringe injection process is governed by a sophisticated algorithm that considers patient-specific parameters, ensuring precise dosage administration. Through extensive testing and real-world simulations, the results demonstrate a significant reduction in human error and improved medication adherence. The system’s architecture integrates secure communication protocols, ensuring data confidentiality and integrity during transmission. An innovative user interface provides healthcare professionals with real-time monitoring and control capabilities, enhancing situational awareness and responsiveness. Furthermore, the SIP’s adaptability to diverse medical environments underscores its versatility in meeting the evolving needs of healthcare institutions. To validate the system’s effectiveness, a comprehensive performance evaluations, including dosage accuracy, response time, and reliability under varying conditions was conducted. Results indicate an impressive dosage precision of 99.8%, showcasing the system’s reliability in critical healthcare scenarios. The IoT connectivity facilitates remote monitoring and control, allowing healthcare providers to intervene promptly in case of anomalies or emergencies. In addition to its technical prowess, the SIP aligns with current healthcare trends by promoting sustainability and cost-effectiveness. The automated system optimizes resource utilization, reduces medication waste, and minimizes the environmental impact associated with traditional manual injection methods. In conclusion, this IoT-based Syringe Injection Pump represents a paradigm shift in medical technology, offering a smart and results-oriented solution for precise medication administration. The successful implementation and validation of this system pave the way for improved patient outcomes, streamlined healthcare workflows, and a more sustainable approach to medication delivery. This research contributes to the ongoing discourse on advancing medical technology and underscores the potential of IoT in shaping the future of healthcare.

Design and Performance of a Linear Flux Pump for the Frascati Coil Cold Test Facility

Design and Performance of a Linear Flux Pump for the Frascati Coil Cold Test Facility