Pump Efficiency Research Articles

Comparative Energy Performance Analysis of Solar Water Pumping Systems Across Diverse Climate Zones

The solar PV system-based water pumping plant is cost-effective in developing countries like India. This study compares remote solar water pumping systems, accounting various factors like site location, system size, and performance, in several climate-sensitive Indian regions. The PVsyst simulation software is used to design the standalone solar water pumping system. Data inputs are obtained from four different climatic locations in southern part of India. A comparative analysis is performed for the four regions based on the solar yield, performance ratio (PR), energy losses, and pump efficiency. The PVsyst simulation analysis shows that the overall pump efficiency ranges between 57% and 66%, and the performance ratio ranges between 51% and 69%. The outcome of the results is useful for making a policy decision about locating the best solar pumping station based on the climate conditions, particularly for remote villages.

Optimization of low-temperature multi-stage submersible pump based on blade load

The multi-stage submersible pump is a power conveyor for low-temperature media, which is conveyed by the rotating of centrifugal impellers. In this study, the impellers of a multi-stage submersible pump were optimized to improve the efficiency under the premise of the constant total blade load and head. Based on the analysis of performance and flow for each stage of the 18-stage submersible pump, the optimization scheme composed of the first stage, the middle stage, and the last stage was determined. The blade outlet angle, average blade wrapping angle, and blade wrapping angle difference were selected as optimization parameters through Plackett–Burman experimental design and significance analysis, and the blade profile was redrawn by changing the blade load distribution. The performance prediction model was built based on the Kriging response surface model, and then, the global optimal blade profile was found by non-dominated Sorting Genetic Algorithm II. The efficiencies of the 3-stage submersible pump and 18-stage submersible pump with optimized impeller increased by 2.35% and 2.01%, respectively. Under the design condition, the flow rate loss and pressure pulsation at the impeller outlet decreased and the stator–rotor interaction between the impeller and guide vane was weakened. This will lead to a reduction in unstable flow such as secondary flow and vortices, and an improvement of flow stability at the impeller outlet.

Grazing by nano- and microzooplankton on heterotrophic picoplankton dominates the biological carbon cycling around the Western Antarctic Peninsula

Over the past 40 years, the significance of microzooplankton grazing in oceanic carbon cycling has been highlighted with the help of dilution experiments. The ecologically relevant Western Antarctic Peninsula (WAP) ecosystem in the Southern Ocean (SO), however, has not been well studied. Here we present data from dilution experiments, performed at three stations around the northern tip of the WAP to determine grazing rates of small zooplankton (hetero- and mixotrophic members of the 0.2–200 µm size fraction, SZP) on auto- and heterotrophic members of the < 200 µm plankton community as well as their gross growth. While variable impacts of SZP grazing on carbon cycling were measured, particulate organic carbon, not the traditionally used parameter chlorophyll a, provided the best interpretable results. Our results suggested that heterotrophic picoplankton played a significant role in the carbon turnover at all stations. Finally, a comparison of two stations with diverging characteristics highlights that SZP grazing eliminated 56–119% of gross particulate organic carbon production from the particulate fraction. Thus, SZP grazing eliminated 20–50 times more carbon from the particulate fraction compared to what was exported to depth, therefore significantly affecting the efficiency of the biological carbon pump at these SO sites.

Two-phase flow investigation of sewage pumps with different tip clearance via computational fluid dynamics and multi-factor ANOVA

Sewage pumps are widely utilized in various applications, including municipal wastewater treatment plants, industrial processes, and residential sewage systems. These pumps are specifically designed to handle the transportation of mixtures consisting of solid and liquid components, commonly observed as two-phase flow. In this study, semi-open sewage pumps with varying clearance sizes have been examined through adjustment of the geometrical model. Multi-factor analysis of variance is employed to investigate the combined influence of different two-phase flow conditions and tip clearance sizes on the performance of sewage pumps. The results show that the performance of the pump decreases significantly as the clearance size increases. Also, the sensitivity of pump efficiency to variations in tip clearance size is contingent upon the flow rate. Under part-load conditions, both particle concentration and clearance size exhibit a notable effect on efficiency. The two-phase flow will greatly enhance the intensity of the unsteady flow near the inlet and outlet of the semi-open impeller, which is the main reason for the performance degradation of the sewage pump. The findings of this research provide valuable insights for enhancing the hydraulic performance and operational stability of semi-open sewage pumps operating under two-phase flow conditions.

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

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

The Transition to Clean Energy and the Role of Building Envelope Efficiency

The electrification of building systems and the improvement of their envelopes must work in tandem to achieve a truly energy efficient and sustainable outcome. Many jurisdictions, including Boston, MA, and Acton, MA, have already released climate action plans, detailing many steps that can be taken to decarbonize. These plans have many specific strategies when it comes to buildings, from incentivizing building improvements on private property to retrofitting municipal buildings. Building electrification includes many aspects, from the electrification of household appliances like stoves to the conversion of traditional heating and cooling systems to heat pumps; an electrification roadmap by Acton lists many specifics when it comes to the electrification of its municipal buildings. The improvement of envelope, encompassing aspects of a building such as its insulation, air sealing, windows, moisture control, and ventilation system, is an aspect of sustainability that is arguably more important than the pure electrification of systems. Envelope improvements will improve heat pump efficiency at colder temperatures, and will result in significant energy use and cost reductions.

Effects of interface model on performance of a vortex pump in CFD simulations

That the predicted head of a vortex pump is higher than that measured experimentally is very common in simulations of turbulent flow in such pumps. To identify why, reported here is a study of the turbulent flow of water in a vortex pump with a specific speed of 76 and fluid domains with 1/8-impeller and whole-impeller geometrical models and smooth walls using the 3D steady Reynolds-averaged Navier–Stokes equations, the standard k–ɛ model, and a scalable wall function in ANSYS CFX 2019 R2. The results show that the aforementioned phenomenon is related to the choice of interface model. With the 1/8-impeller model, the head predicted by the frozen rotor model agrees with the experimental head. By contrast, the transient rotor model provides a reasonably accurate head against the experimental head but requires huge computing resources and overestimates the pump efficiency, and the stage model is unsuitable for predicting the head of the pump. The flow patterns in the vaneless chamber and impeller predicted with the 1/8-impeller model are more uniform because of artificial fluid mixing on the interface than those predicted with the whole-impeller model by using the frozen rotor model, and the flow patterns predicted with the whole-impeller model by using the transient rotor model are in between. The hydraulic performance of the pump is predicted with the 1/8-impeller model and frozen rotor model at various viscosities, and the flow-rate, head, and efficiency correction factors are determined and correlated with the impeller Reynolds number.

The influence of blade curvature radius on the internal unsteady characteristics of a centrifugal pump

AbstractTo study the influence of the blade curvature radius on the flow‐induced vibration and noise of the centrifugal pump, the internal sound field of the IS 80‐65‐160 centrifugal pump was numerically calculated by adjusting the blade wrap angles to change the blade curvature radius. The RNG (Reynolds Time Average Simulation) turbulence model was selected for the numerical calculation of the centrifugal pump. The numerical simulation of the whole flow channel of the centrifugal pump was carried out using Ansys Fluent software, and the external characteristic curve of the centrifugal pump was obtained. The influence of different blade wrap angles on the internal pressure, velocity and Turbulent Kinetic Energy of the centrifugal pump was obtained. On the basis of the sound–structure coupling equation, the unsteady sound field of the centrifugal pump was calculated, and the time domain and frequency domain characteristics of the pressure pulsation at each monitoring point were obtained. The calculation results showed that the dynamic and static interference between the impeller and the volute tongue mainly caused the vibration of the centrifugal pump. By appropriately increasing the blade wrap angles, the pressure pulsation in the volute fluid domain could be effectively reduced. The vibration and noise test bench of the centrifugal pump was set up to verify the test. The experimental results showed that at the double‐blade frequency, the variation trend of the experimental value and the simulated value of the outflow flow‐induced noise of the centrifugal pump were consistent, which verified the accuracy of the sound field simulation calculation. When the blade wrap angle , it could effectively reduce the internal sound pressure level and the flow‐induced vibration and noise of the centrifugal pump. By adopting measures such as grid encryption at the position of the tongue, nonstationary calculation and comparison of different turbulence models, the accuracy of the calculation results of the internal flow field and sound field of the centrifugal pump is effectively improved, and the accuracy and reliability of the experimental results are ensured. The above research results had certain reference significance and application value for improving the working efficiency of centrifugal pumps and reducing flow‐induced vibration and noise.

THE IMPACT OF TEMPERATURE ON SUCTION PERFORMANCE OF GEAR PUMPS

Through meticulous experimental setups, including a closed-loop system and precision temperature controllers, our study systematically explores the impact of temperature variations on gear pump behavior. This observed phenomenon is attributed to fluid viscosity changes and underscores the intricate interplay between thermal dynamics and gear pump efficiency. In the comparative analysis, our findings are bench-marked against industry standards, revealing both congruities and disparities. The study goes beyond the immediate implications by presenting a sensitivity analysis of different gear materials concerning temperature variations. This work not only contributes to the theoretical understanding of fluid machinery but also has practical ramifications. The presented advanced statistical insights, including a cor-relation matrix, add depth to our comprehension of the interconnected factors influencing gear pump operation. In conclusion, this study provides a nuanced understanding of temperature's influence on gear pump suction performance. By combining empirical evidence with advanced statistical insights, our findings offer practical insights for optimizing gear pump efficiency in varying temperature conditions, ultimately contributing to the evolving landscape of fluid machinery research. Keywords: gear pump, temperature variations, suction performance, fluid dynamics, experimental setup.

Strategy to Improve the Performance of The Ngagel I Water Treatment Plant (IPA) in Pdam Surya Sembada Surabaya City Through Increasing Pump Efficiency

PDAM Surya Sembada Surabaya’s energy cost in 2021 amounted to Rp 147.654.439.569, with an energy cost ratio of 24.37%, and the electricity cost of production unit accounted for 76% of the total energy consumption of PDAM. The relatively flat topography does not allow gravity-based systems for water supply. Aging equipment has decreased overall pump efficiency (ηpt) and increased energy consumption, particularly in Ngagel I WTP, built in 1922, necessitating an energy audit. Energy audit includes measuring pump flow rate and pressure, power, voltage, current, power factor, pump and motor pump rotation and temperature. Analysis shows that raw water pumps U2, U3, U5, and S1 and distribution pumps U1, U3, and T4 are still in good condition. However, raw water pump U6 and distribution pumps U6, S1, and S2 require reconditioning and impeller adjustment due to declining efficiency. Furthermore, PDAM must inspect the distribution pump T1 with the lowest efficiency value (49.77%) to determine the appropriate repairs. The research results are action recommendations expected to serve as input and considerations for PDAM in their efforts to improve energy efficiency.

Southern Ocean Biological Pump Role in Driving Holocene Atmospheric CO2: Reappraisal

AbstractChanges in Southern Ocean biological pump efficiency are frequently invoked as a source of glacial/interglacial CO2 variability. It was recently suggested that Southern Ocean biological pump weakening also contributed to Holocene CO2 increase. Here we test the causes and downstream effects of biological pump inefficiency during the Holocene. We first provide evidence that a southward shift of the South Westerly Winds, was likely the cause of increasing upwelling in the Southern Ocean leading to local biological pump weakening as reflected in fossil‐bound δ15N. We then introduce a series of ultra‐high resolution (6 m/ky) productivity records from the Chilean Margin to determine the fate of Southern Ocean nutrients. A compilation of records from Pacific sites supports export and complete consumption of preformed Southern Ocean nutrients, which might have reduced the contributions of Southern Ocean marine source to the Holocene increase in atmospheric CO2.

Best Practices Guide for Centrifugal Pump Maintenance

This study examines the efficiency of centrifugal pumps, which enhance fluid movement by converting kinetic to dynamic potential energy via an impeller. Maintenance strategies—regular, predictive, and preventive—are analyzed for their impact on pump longevity and reliability. Results demonstrate that effective maintenance reduces operational costs and extends pump life, suggesting significant performance improvements across industrial applications. Highlight : Effective maintenance boosts pump longevity and reliability. Regular, predictive, and preventive maintenance methods analyzed. Significant performance improvements achievable with proper maintenance. Keywords: Centrifugal pumps, Maintenance strategies, Pump efficiency, Operational costs, Industrial applications

Design method based on a new slip-diffusion parameter of centrifugal pump for multiple conditions in wide operation region

Centrifugal pumps are widely used in industrial production, agricultural irrigation, water transportation, energy storage pump station and ocean engineering, and the development prospect of centrifugal pump is to work in a wide operation region with high efficiency. In this work, the achievement of high-efficiency operation for multiple conditions in a wide operation region is strenuously realized by a new design method from the perspective of flow mechanism analysis and theoretical derivation. A new dimensionless slip-diffusion parameter Φ on consideration of the slip effect and diffusion effect in impeller is proposed. On the basis of the new parameter Φ, a new design method of centrifugal pump is established to improve the pump efficiency for multiple conditions in a wide region. Two centrifugal pumps with different specific speeds of 102 and 127 are designed to validate the proposed design method. When the slip-diffusion parameter Φ ≈ 0.677, the centrifugal pump can achieve the maximum average efficiency for multiple conditions. For Φ < 0.677, the pump efficiency rapidly drops at the high flow rate region. For Φ > 0.677, the pump efficiency rapidly drops at the low flow rate region. Two centrifugal pumps are numerically simulated to obtain the flow pattern, and the entropy production method is used to analyze the relationship between flow field and energy performance of the pumps. Entropy production mainly appears at the blade suction side and the impeller outlet. For different flow rates, the total entropy productions of pumps with Φ ≈ 0.677 are always the minimum.

Resizing of Irrigation Pumps Used for Heap Leaching in a Mine: Case of SOMAÏR

The aim of this study is the analysis and resizing of irrigation pumps used in heap leaching at the Mines de l'Aır company. This company is located in the Arlit department in the Agadez region of Niger. This work essentially consisted of checking the current pumps, integrating the new parameters and choosing the right pumps, either by respecting the current standard or by proposing other types of more efficient pumps. The study revealed that for the 3rd stage pumping circuit, the Total Head (HMT) value of 33.58 m is lower than that of the pumps, which is 34.03 m. This pump sends the fluid to the desired heap height with a pressure of 0.5 bar, whereas the desired pressure for watering is around 2 bar. The result: a drop in uranium juice production. The pump does not exhibit cavitation, as the Net Positive Suction Head (NPSHD) is equal to 4.71 m, a value that far exceeds the NPSHr , which is equal to 1.44 m. Given that at 1485 rpm the pump is unable to deliver a pressure of 6 bar with the valve closed, we can say that the pump has lost its performance. By the 3rd stage, the HMT of the circuit is equal to that of the pump, so the pump will still be able to deliver the fluid to the piles, but at a very low pressure, and even if both pumps are switched on simultaneously, the flow rate will not exceed 150 m3 /h. This means that irrigation will be very poor, resulting in mediocre uranium juice production. With a pump efficiency of 61.98%, we can say that the pump is operating under optimum conditions and does not suffer from cavitation, as the NPSHD is well above the NPSHr . For the 4th stage circuit, the CPKN 100-404 pump driven at 1650 rpm gives a flow rate of 175 m3 /h and a head of 57.91 M.C.E. The MegaCPK 125-80-380 pump driven at 1750 rpm gives a flow rate of 190 m3 /h and a head of 60.28 M.C.E. The CPKN 150-440 pump, driven at 1450 rpm, operates at 230 m3 /h and 67.55 M.C.E. The MegaCPK 150-125-380 pump, driven at 1750 rpm, delivers 250 m3 /h and a head of 71.71 M.C.E.

Performance prediction and optimization of hydrogenation feed pump based on particle swarm optimization – least squares support vector regression surrogate model

Due to high power consumption and low energy efficiency of the hydrogenation feed multistage pump, conducting structural optimization design and reducing energy losses for this pump is necessary. In this study, an optimization method based on the particle swarm optimization (PSO) algorithm and least squares support vector regression (LSSVR) surrogate model is proposed. The head and efficiency are taken as the optimization objectives of the multistage pump, and the optimization design of the two impellers is carried out. Through the optimization of the surrogate model, the head and efficiency of the multistage pump are increased by 3.99% and 2.91%, respectively. It is found that the optimized impeller has more stable flow characteristics than original impeller. Further, the entropy production method is introduced to analyze the energy loss of pump. The result shows that the pump optimized by PSO-LSSVR surrogate model can reduce 9% energy consumption under nominal flow rate. It is attributed to the inhibitory effect of the optimization scheme on the horseshoe vortex at leading edge and the wake vortex at trailing edge of impeller. This study provides a new idea for the optimization design of high efficiency and low energy consumption of multistage centrifugal pumps.

Unveiling the evolution of phytoplankton communities: Decades-long insights into the southern Yellow Sea, China (1959–2023)

We obtained historical and observational data on phytoplankton communities from 1959 to 2023 to explore the responses of the phytoplankton community structure to long-term environmental changes in the southern Yellow Sea (SYS), China. The results revealed a decrease in the proportions of diatom cell abundance within the phytoplankton community by 8 %, accompanied by a corresponding increase in that of dinoflagellates. Dominant phytoplankton species were mainly chain-forming diatoms before 2000, and large dinoflagellate species from the genera Tripos and Noctiluca increased their dominance after 2000. Warm-water phytoplankton species have increased in dominance over the study period. Correlation analysis revealed that the ocean warming and alterations in nutrient structure (N/P and Si/N ratios) were mostly responsible for the long-term evolution trend, and these changes may result in an increase in dinoflagellate harmful algal blooms, reduced efficiency of the biological carbon pump, and heightened hypoxia in the future, which should draw our attention.

Numerical study of the laser isotope separation of optically pumped 102Pd

The feasibility of laser isotope separation of 102Pd through pulsed laser optical pumping followed by isotope selective photoionization has been studied through density matrix formalism. The effect of various parameters such as bandwidth of the excitation lasers, intensity of the lasers and Doppler broadening of the atomic ensemble on the efficiency of optical pumping and isotope selective photoionization have been evaluated. The optimum number density in the laser-atom interaction region has been derived from the studies of the effect of charge exchange collisions on the degree of enrichment. It has been shown that it is possible to enrich 102Pd up to ~ 23.7% at a production rate of 1.1 mg /h. The achievable degree of enrichment through this photoionization scheme is higher than the previously reported laser isotope separation process. The radionuclidic purity of the irradiated enriched mixture has been found to be suitable for medical applications.

Optimization of Magnetic Pump Impeller Based on Blade Load Curve and Internal Flow Study

Compared to traditional centrifugal pumps, magnetic pumps are widely used in industries such as chemical, pharmaceutical, and petroleum due to their characteristics of leakage-free operation and the ability to transport toxic and corrosive fluids. However, the efficiency of magnetic pumps is relatively low. Improving the efficiency of pumps helps to reduce energy loss and lower industrial costs. In this study, a magnetic pump was chosen as the research subject. The study aims to improve the efficiency and stability of the magnetic pump by optimizing the impeller blades based on the load curve. A combined approach of a numerical simulation and experimental verification was used to investigate the impact of the anterior loading point (AL), posterior loading point (PL), and slope (SL) in the blade loading curve on the pump’s performance. The slope, which had the most significant impact on pump performance, was selected as the dependent variable to analyze the internal pressure pulsation and main shaft radial force of the magnetic pump. The research found that the hydraulic performance test results of the magnetic pump were in good agreement with the simulation results. When efficiency is used as the optimization objective, the anterior loading point should be moved as far back as possible, and the posterior loading point should be moved as far forward as possible. Through the study of internal pressure fluctuations and radial forces within the pump, the radial force distribution is sequentially as follows: the anterior loading method, posterior loading method, and middle loading method at a rated flow rate. The maximum pressure pulsation amplitude was near the volute casing diffuser area. Compared to the original pump, the optimized magnetic pump showed a 5.05% improvement in hydraulic efficiency under the rated conditions. This research contributes to enhancing the performance and efficiency of magnetic pumps, making them more suitable for various industrial applications.

Current progress in semi-batch reverse osmosis for brackish water desalination

Semi-batch reverse osmosis (SBRO) is an innovative membrane process renowned for its compact system and high recovery in desalination and water reuse. While academic research provides valuable insights, aligning it with real-world implementation is crucial. The study aims to understand the current progress in SBRO for brackish water desalination by identifying performance disparities between academic research and practical applications, evaluating practical performances under realistic parameters, and proposing future research directions. Through gathering and comparing data from SBRO research and practices, performance disparities between theoretical projections and real-world applications were identified. The analysis revealed that specific energy consumption (SEC) in academic research had been underestimated by applying impractical pump efficiencies, and permeate quality was often neglected. To assess the practical SEC and permeate quality of SBRO, engineering design calculations were performed with realistic parameters. Based on the evaluation, the importance of maintaining suitable recovery and incorporating a permeate tank was emphasized to avoid a significant increase in SEC and to stabilize water quality, respectively. Given the challenges of the SBRO system, the discussion further outlined research directions addressing issues in energy efficiency, permeate quality, membrane fouling/scaling, and practical design/operation. It recommended considering these practical aspects for the broader applications of SBRO.

Study on the Hydrodynamic Performance of Swing-Type Flapping Hydrofoil Bionic Pumps Affected by Foil Camber

The flapping hydrofoil bionic pump is an innovative hydrodynamic device that utilizes flapping hydrofoil technology. Flapping hydrofoil bionic pumps are crucial in addressing issues like inadequate river hydropower and limited water purification capabilities in flat river network regions. Optimizing the foil characteristics is essential for enhancing the hydrodynamic efficiency of the flapping hydrofoil bionic pump. This study investigates the impact of foil camber parameters on the hydrodynamic performance of swing-type asymmetric flapping bionic pumps. The NACA series standard foils with varying cambers are analyzed using the overlapping grid technology and finite volume method. The thrust coefficient, flow rate, pumping efficiency, and flow field structure of the flapping hydrofoil bionic pump are examined under pressure inlet conditions with the foil camber. The findings indicate that increasing the foil’s curvature within a specific range can greatly enhance the maximum values of thrust coefficient, propulsive efficiency, and pumping efficiency of the flapping hydrofoil bionic pump. Specifically, when the foil curvature is 6%c, the maximum value of the instantaneous thrust coefficient of the flapping hydrofoil bionic pump is significantly improved by 31.25% compared to the symmetric foil type under the condition of an oscillating frequency of f = 1 HZ. The flapping hydrofoil bionic pump achieves its maximum pumping efficiency when the oscillation frequency is within the range of f ≤ 2.5 Hz. This efficiency is 11.7% greater than that of the symmetric foil, and it occurs when the foil curvature is 8%c. Within the frequency range of f &gt; 2.5 Hz, the flapping hydrofoil bionic pump that has a foil curvature of 6%c exhibits the highest enhancement in pumping efficiency. It achieves a maximum increase of 12.8% compared to the symmetric foil type. Nevertheless, the average head was less than 0.4 m, making it suitable for ultra-low-head applications.