Blade number effects on performance and internal flow dynamics in high-speed coolant pumps

Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(1)

Published: Jan. 1, 2025

The high-speed coolant pump is a critical component in battery energy storage systems, responsible for circulating heat transfer fluid and enabling efficient thermal exchange. This study investigates the effect of blade number (Z = 4–9) on pump's performance internal flow characteristics through experimental numerical methods. Results show that as increases, head efficiency initially rise then decline, with Z 6, 7, 8 achieving comparable at 1.0Qd. While changes minimally affect disk, volumetric, volute efficiencies, they significantly influence hydraulic impeller efficiencies. Pressure distribution analysis reveals increasing to 6 7 reduces low-pressure region inlet improves uniformity. Flow shows separation “jet-wake” but an excessive blades also raises turbulent kinetic energy, compromising stability. Similarly, entropy production decreases rises again 9, resulting reduced performance. Overall, follow “inverted U-shaped” trend highlighting importance selecting appropriate improve conditions, minimize losses, enhance operational provides valuable insights optimizing design pumps.

Language: Английский

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Role of reinforcement on the tribological properties of polytetrafluoroethylene composites: A comprehensive review

Polymer Composites, Journal Year: 2024, Volume and Issue: 45(16), P. 14475 - 14497

Published: July 24, 2024

Abstract Polytetrafluoroethylene (PTFE) is widely used in tribological applications. However, it faces challenges due to its high wear rate. Reinforcement of additives PTFE reduces rate by up 10,000 times dry conditions. Infusing metallic filler materials like Al, Cu, and Pb improves performance but increases the coefficient friction (COF). may not be suitable for corrosive environments potential metal reactivity. Reinforcing composites with carbon‐based weight, properties, lowers COF. Pre‐treated enhance bonding improved anti‐friction anti‐wear properties. are journal bearings, bearing pads, ball bearings their excellent low‐speed, low‐load lubrication They outperform Babbitt alloy except heat conductivity. can also as a solid lubricant combined performance. Apart from it, achieving an optimal combination properties all forms reinforcement challenging difficulty determining exact values multiple specific types reinforcement. This article provides comprehensive review that delves into significant findings pertaining application technology. Highlights Metals fillers improve tribo‐properties. thermal stability polymeric materials. Estimation tribo‐thermal challenge. Testing conditions greatly impact low‐speed/load

Language: Английский

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Assessment of viscosity effects on high-speed coolant pump performance

Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(5)

Published: May 1, 2024

The high-speed coolant pump facilitates thermal regulation in electric vehicle components, including batteries and motors, by circulating an ethylene glycol solution. This commonly used fluid exhibits a notable negative correlation with temperature terms of viscosity. Numerical simulations investigate the transient dynamics operating at 6000 rpm, driving flow various temperatures. A test rig is established, performance evaluated under different conditions. numerical temperatures align well experimental outcomes. Decreasing temperatures, from 100 to −20 °C, lead reduced head efficiency due increased Specifically, rate 30 L/min, decreases 40.03% 44.19%. With escalating viscosity, best point shifts toward lower rates. Notable impacts on both disk hydraulic are observed viscosity fluctuations. It exerts minimal influence volumetric elevated rates but has substantial impact Increased causes uneven pressure distribution within pump, altering velocity profiles impeller. High-viscosity fluids tend form large-scale vortex structures around blades, reducing thrust exerted blades fluid. Higher results larger increasing frictional resistance. study findings provide valuable insights for advancement high-efficiency, energy-saving, pumps tailored vehicles.

Language: Английский

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A Novel Method to Achieve Fast Multi-Objective Optimization of Hydrostatic Porous Journal Bearings Used in Hydraulic Turbomachine

Journal of Fluids Engineering, Journal Year: 2023, Volume and Issue: 145(5)

Published: Feb. 27, 2023

Abstract The hydrostatic journal bearing equipped with a carbon-fiber-reinforced carbon-based porous bushing is employed in the hydraulic turbomachine. exhibits high load capacity, but may unduly consume pressurized lubricant. This study aims to maximize capacity and minimize feeding power. radius, nominal clearance, length, thickness, pressure, material permeability are selected optimize. A fast optimization method proposed, integrating an in-house solver (PBS), sampling method, surrogate model, genetic algorithm. Behind PBS, theoretical flow model based on Reynolds lubrication equation Darcy established, new numerical finite difference proposed. PBS substitutes ansysfluent by calculating performances accurately instantly, which first novelty facilitate optimization. Then, artificial neural networks trained as error-free time-efficient models produce objectives evolution, second acceleration highlight. running time reduced significantly. improved 68.1%, whereas power declines 50.5%. In optimized case, sharp pressure hump leads greater while radial velocity decreases, resulting

Language: Английский

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PTFE/carbon composite radial deep groove ball bearings: Part 1–tribological characterization suitable for ball bearing applications

Polymers and Polymer Composites, Journal Year: 2025, Volume and Issue: 33

Published: March 1, 2025

Polytetrafluoroethylene (PTFE) is a self-lubricating, highly stable, high-performing polymer that has expanded its usage in bearing tribology. However, application ball bearings still limited. This article explores using PTFE/carbon composites to evaluate their suitability for radial deep groove ball-bearing applications. The proposed work divided into two parts. first part focuses on the tribological characterization of through ball-on-disc test and examines effect reinforcement performance. second fabricating analysing characteristics. In part, experiment was performed pure PTFE 25% carbon-filled (CR25) measure coefficient friction (COF) wear rate. These materials were subjected three loading conditions at particular speed silicon nitride balls (Si 3 N 4 ). recorded throughout interaction, specific rates calculated. After completing tests, tracks analyzed scanning electron microscope Contracer.

Language: Английский

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Performance Optimization of a Multi-groove Water Lubricated Journal Bearing with Partial Slip by Taguchi Analysis

Arabian Journal for Science and Engineering, Journal Year: 2023, Volume and Issue: 49(2), P. 2249 - 2267

Published: Aug. 24, 2023

Abstract The importance of preserving the ecological balance has paved way for developing water lubricated bearings marine vessels and other various applications. These have found widespread applications in high pressure pumps, water-power plants power generation stations sea, mining industries, ships, boats submarines. To investigate performance envelope a journal bearing (WLJB) with partial slip/no slip pattern, multi-groove model is developed analyzed using CFD present study. Taguchi analysis method utilized to determine highest influential parameter affecting distribution load-carrying capacity bearing. From method, optimum values identified design parameters such as attitude angle, groove height number grooves are 60°, 9°, 7 mm 2, respectively. For combination model, higher load 1484.5 N attained. Approximately, 2.88 times increase peak pressures noted from current optimal by comparing previous findings. Results indicated that angle most capacity. Partial conditions applied at grooved surfaces designed based on parameters. Influence varying intensity simulation. Appropriate selection regions amplitude play major role influencing

Language: Английский

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Thermohydrodynamic performance of convergent slider bearings using different placement of square micro-textures and slip boundary

Physica Scripta, Journal Year: 2023, Volume and Issue: 99(2), P. 025015 - 025015

Published: Dec. 28, 2023

Abstract The present numerical study investigates the thermohydrodynamic performance of inclined/convergent slider bearings using different placing textures and slip region. Mass-conserving Elrod cavitation model with boundary is used to analyze static variables. Due better fluid retain-ability, Square-shaped micro-textures have been used. coefficient for on bearing surface taken as 9 μ m. As reported previously convergent bearings, optimal convergence ratio (K) value maximum lies between 1 1.4. Therefore, in paper, K 1.2. It was observed that location greatly influence performance. When regions are placed near inlet region bearing, a reduction shear stress availability lubricant inlet, resistance flow reduces, increasing intake. Further, partial an abrupt obstruction occurs at slip/no-slip interface, which increases hydrodynamic pressure improves load-bearing capacity bearing. Moreover, due less friction observed, various slip-textured showed average temperature compared conventional In end, updated combined presented terms findings current work would be helpful researchers selecting optimum inclined under operating conditions.

Language: Английский

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Effect of Gasket Wear Rate on Hydraulic Performance and Internal Flow of Multistage Centrifugal Pump with Floating Impellers

Journal of Physics Conference Series, Journal Year: 2024, Volume and Issue: 2854(1), P. 012048 - 012048

Published: Oct. 1, 2024

Abstract The sealing gaskets of multistage centrifugal pumps are prone to wear during operation. This study investigates the influence gasket rate on hydraulic performance and internal flow field through numerical simulations. As increases, both efficiency head coefficient pump gradually decrease. When is completely worn out, decreases by 5.6% 9.5% compared unworn condition. Analysis reveals that front side chamber most significantly affected wear. wears, velocity within increases gradually, high-entropy production zone expands, thereby affecting pump. findings this provide practical engineering insights for enhancing operational pumps.

Language: Английский

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Dynamic Analysis of Radial Journal Bearing-Rotor System Based on the Meshless Barycentric Rational Interpolation Collocation Method

Lubricants, Journal Year: 2024, Volume and Issue: 12(12), P. 431 - 431

Published: Dec. 4, 2024

This study focuses on a rigid rotor supported by radial journal bearings. Initially, models for the unsteady oil film force in bearing lubrication and dynamics of bearing-rotor system are established. Subsequently, Reynolds equation dynamic lubricating films is discretely solved using meshless barycentric rational interpolation collocation method. By combining this with motion axis orbit, pressure distribution, response rotor, orbit calculated. Furthermore, investigates at different rotational speeds, both without considering unbalanced loads. Finally, influence step load stability analyzed, revealing that applying an appropriate to can effectively mitigate oscillation conditions. The findings hold significant reference value practical utility engineering applications.

Language: Английский

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The Discussion of the Influence of Eccentricity Ratio on Lubrication Characteristics of Fluid Lubricated Bearings

Recent Patents on Engineering, Journal Year: 2023, Volume and Issue: 18(2)

Published: March 1, 2023

Abstract: The operating quality of bearings has also led to higher criteria with the growing status manufacturing industry in social production. eccentricity ratio bearing system is particularly susceptible change during operation as a result external load, which direct impact on lubricating properties. On one hand, reasonable will improve bearing's lubrication performance, increase stability, and better meet processing requirements; other it uncontrollable behavior may even cause real world deviate from theoretical design model. study aimed analyze discuss current findings ratio. More than 100 related articles have been summarized, research results, such load-bearing characteristics, are discussed. This paper discusses progress problem fluid-lubricated bearings, well effect characteristics for using different media. Active control measures mitigate negative changing ratios presented. After analyzing summarizing relevant literature, found that important factors affecting bearings.

Language: Английский

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