Improving the hydraulic performance of a high-speed submersible axial flow pump based on CFD technology

Deleted Journal, Journal Year: 2024, Volume and Issue: 1(1)

Published: Feb. 29, 2024

The hydraulic performance of a high-speed submersible axial flow pump is investigated to reduce its energy consumption. A more efficient and stable optimization method that combines parametric design, computational fluid dynamics, computer algorithm proposed. main aim broaden the high-efficiency operating zone, so average efficiency under multiple conditions optimized while considering rotor–stator matching. design-of-experiments radial-basis-function neural network are combined form platform, automatic design realized through repeated execution simulation. loss mechanism inside studied in depth via entropy generation rate, regression analysis shows influenced mainly by blade angles. After optimization, target increased 8.34%, field distribution channel vortex controlled effectively. Finally, results validated experiment. proposed approach has advantages saving manpower obtaining globally optimal solutions.

Language: Английский

---

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

---

Effect of Trimmed Rear Shroud on Performance and Axial Thrust of Multi-Stage Centrifugal Pump With Emphasis on Visualizing Flow Losses

Journal of Fluids Engineering, Journal Year: 2023, Volume and Issue: 146(1)

Published: Sept. 16, 2023

Abstract Multi-stage centrifugal pumps are frequently used in high-lift applications and consume considerable energy, but suffer from poor performance large axial force. The rear shroud of impeller is trimmed for reducing thrust, this degrades performance. This study analyzes degradation optimizes Experiments simulations conducted on different ratios to front (λ). Total pressure losses calculated, flow visualized using the entropy generation method. Both measured simulated performances decrease as trimmed. Designs with λ meet head coefficient requirement 1.1. However, 0.86 has best efficiency 42.7%, 0.83 reaches 42.5%, 0.8 shows lowest 39.9%. Efficiency middle channel improves trimmed, cannot offset increased side chamber. Entropy production exacerbated passage between chamber due collision impeller-driven pressure-driven backflow. When reduced by 0.03, thrust drops 7%. To compromise should be designed at 0.83.

Language: Английский

---

Transient numerical investigation on hydraulic performance and flow field of multi-stage centrifugal pump with floating impellers under sealing gasket damage condition

Physics of Fluids, Journal Year: 2023, Volume and Issue: 35(10)

Published: Oct. 1, 2023

Multi-stage centrifugal pumps with floating impellers provide a convenient means of adjustment to meet diverse head requirements. These utilize sealing gaskets minimize leakage losses and restrict impeller axial motion. However, the impact gasket breakage on hydraulic performance internal flow remains uncertain. To investigate this, novel dynamic mesh simulation method is proposed enable simultaneous motion rotation impeller. Validation numerical simulations experiments performed. Transient influenced by motion, lagging field response. Head coefficient efficiency curves exhibit asymmetric triangular functions higher fluctuations compared fixed position. At design condition, floating, ranges from 0.7 1.9, while 29.7% 60.1%. Among various loss ratios, ratio exhibits highest magnitude, followed ratio, shroud friction being smallest. Entropy production reveals significant influence oscillation local loss. The causes drastic velocity pressure in both time space.

Language: Английский

---

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

---

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

---

Unsteady Simulation and Analysis of Energy Loss Mechanism of a Vertical Volute Pump Under Stall Conditions

Journal of Fluids Engineering, Journal Year: 2023, Volume and Issue: 145(8)

Published: March 9, 2023

Abstract This study comprehensively investigates the flow features and energy loss mechanisms under stall conditions based on computational fluid dynamics (CFD) hydraulic visualization techniques. The three-dimensional unsteady Reynolds-averaged Navier– Stokes (URANS) equations were solved using shear stress transport (SST) k–ω turbulence model. Furthermore, entire domain of vertical volute pump was considered to capture boundary behavior accurately. results illustrate that critical condition occurs at 0.7Qd, where H–Q curve exhibits a positive slope, deep 0.65Qd. growth rate from is 182.2%. In condition, secondary vortex appears impeller inlet. A high suction side trailing edge in caused by reduction effective inflow area. blade guide vane primarily due friction condition. By contrast, outlet mainly impact rear gunner. effect can result losses near tongue. entropy production analysis demonstrates diffuser are literately greater than inlet pipe. Hence, optimization such components be taken into consideration future works for performance improvement.

Language: Английский

---

Performance Optimization of Slotted Blades for Low-Specific Speed Centrifugal Pumps

Advances in Civil Engineering, Journal Year: 2023, Volume and Issue: 2023, P. 1 - 16

Published: Jan. 5, 2023

Centrifugal pumps are widely used for the transport of fluids, but low-specific-speed centrifugal have problems with serious backflow and low efficiency. In this paper, a pump specific speed 55 is as research object. By combining numerical simulation orthogonal experiment, pressure distribution velocity flow channel analyzed, priority each geometric factor slits on performance determined, parameter structure slotted blade optimized by entropy weight TOPSIS, optimal impeller slit solution obtained. The results show that balance head efficiency, order influence factors is: center width b > diameter D > shrinkage ratio f > depth h > deflection angle β . combination geometry parameters 3 m , 200 m 0.5, 6 m 20°. Through ANSYS FLUENT experiment closed system, confirmed hydraulic improved.

Language: Английский

---

A Three-Dimensional Slip Velocity Model for Water-Lubricated Hydrodynamic Journal Bearings

Journal of Marine Science and Engineering, Journal Year: 2022, Volume and Issue: 10(7), P. 927 - 927

Published: July 5, 2022

Hydrodynamic journal bearings, coated with polytetrafluoroethylene (PTFE) and lubricated by water, have been widely used in ships large-scale pumps, the function is to maintain stability of rotor system. However, slip velocity exists on PTFE-coated surface, whose effect still an open question. This study aims investigate static characteristics water-lubricated hydrodynamic bearings under three-dimensional boundary conditions. Firstly, non-slip condition, CFD (computational fluid dynamics) method ANSYS Fluent verified based Reynolds lubrication equation literature. Then, a that Navier condition proposed embedded into Fluent. Finally, effects length are analyzed. Under same eccentricity ratio, increase length, load capacity decreases due decrease pressure circumferential gradient, friction power decreases. ratio attitude angle, increase. angle insignificant. paper could provide reference for studying bearing.

Language: Английский

---

Mixed-flow pump performance improvement based on circulation method

Frontiers in Energy Research, Journal Year: 2023, Volume and Issue: 11

Published: April 6, 2023

Mixed-flow pumps have been extensively employed in daily life, improving their energy characteristics contribute to the reduction of consumption worldwide. In this study, overcome decrease optimization upper limit caused by using a single type parameter as design parameter, typical mixed-flow pump was chosen for and its impeller parameterized five geometric eight hydrodynamic parameters. With head efficiency constraint objective respectively, 27 schemes were constructed Taguchi method. The influence factors analyzed based on range regression analysis. mechanism elucidated entropy production result reveals that parameters significantly impact pump’s characteristics. optimized model is 12.43m, which meets constraints, while increases 3.2%–88.51%. Therefore, considering both workable necessary. This paper can provide practical instructions optimal different turbomachines.

Language: Английский

---