Search

An accurate and real-time prediction has been urgently required for the pressure increment performance of centrifugal pumps under gas-liquid conditions during transportation. However, there is no appropriate prediction model for the pressure increment of the centrifugal pump at present, due to the complex gas-liquid flow. Machine learning can be widely expected to serve as a new idea for the performance prediction of centrifugal pumps. In this study, a machine learning model and database were established to investigate the effects of the inlet gas volume fraction, the rotational speed, and the liquid flow rate on the two-phase pressure increment performance of the pump. The results show that the inlet gas volume fraction was a direct factor for the deterioration of pump performance. The pump rotational speed and the liquid flow rate were greatly contributed to the improved performance of pump pressure increment. Three parameters were employed as the input features. The 234 sets of sample points from the experiment were divided into the training set (187 sample points) and test set (47 sample points) with the ratio of 8:2. Four models were constructed after pre-processing the data using Linear Regression (LR), BP Neural Network (BPNN), Support Vector Machine (SVM), and Random Forest (RF). The minimum Mean Square Error (MSE) was used to determine the optimal higher-order term regression function of the LR model, the optimal number of iterations, and the number of hidden layer neurons in BPNN. The grid search and 10-fold cross-validation were used to determine the optimal penalty coefficients and kernel parameters of the SVM, the optimal number of decision trees, and the minimum number of samples on leaf nodes in RF. Then, the Mean Relative Error (MRE), the Root Mean Square Error (RMSE), the determination coefficient (R²), and the confidence level were introduced as the evaluation indexes. The prediction ability of different models was evaluated on the training, the test, and the total data set. The results show that the RF model presented the best ability to predict the pressure increment of the pump, followed by the SVM, the BPNN, and the LR model. In the total data set, the MRE, RMSE, and R² of the predicted pressure increment by RF model were 3.51%, 1.06 kPa, and 0.993, respectively, and the relative error was no more than ±15% under the confidence level of 94.44%. The LR, BPNN, and SVM model failed to represent the characteristics of pump pressure increment, while the RF model performed better to characterize this trend near the pump surging region. It also needed to improve the pressure increment prediction of the RF model around the surging region under a small liquid flow rate. In addition, the importance of input parameters was also evaluated on the pressure increment by RF. Consequently, the rotational speed was the most important parameter on the pressure increment with a value of 52.67%, followed by the inlet gas volume fraction, and the liquid flow rate with 45.41% and 1.92%, respectively. Therefore, the gas-liquid two-phase performance prediction model using RF can be widely expected to better predict the two-phase pressure increment of centrifugal pump. The finding can also provide a strong reference for the design and selection of the centrifugal pump. [ABSTRACT FROM AUTHOR]

Pumps are energetic devices that are present in a wide range of industries. Their installed power varies from a few tens of watts up to hundreds of megawatts. As the energy consumption is connected with global warming and climate change, the development of pumps that have good characteristics is very important. Theoretical and experimental methods have long been utilized in the development of pumps, but recently much research has been carried out with the help of Computational Fluid Dynamics (CFD) analysis. Certain numerical analyses can be of high quality and accurate, but special operational phenomena still occur, where special attention is required when performing analysis. This category includes operating regimes outside the Best Efficiency Point (BEP), the formation of inlet recirculation, cavitation, and the influence of wall roughness on all the above characteristics. The current paper presents the main problems that developers face when numerically analyzing the above-mentioned special operating regimes. Both numerical and experimental results are considered. [ABSTRACT FROM AUTHOR]

The paper provides brief information regarding the implementation of pilot projects on the use of power systems based on solar photovoltaic plants to provide electricity to deep-well pumps and drip irrigation equipment, as well as a system for technical and drinking water filtration, taking into account the round-the-clock regime. This is done to ensure the sustainable development of agriculture on irrigated lands and increase the efficiency of the use of water and land resources in the Fergana Valley, with the participation of the World Bank and the European Union. A monitoring system is proposed that simultaneously measures, collects, analyzes, and transmits photovoltaic plant data. The system is built on the basis of the Internet and cloud technologies to study the production capacity of the plant depending on the ambient temperature. [ABSTRACT FROM AUTHOR]

Secondary unit, in term of application, is the combination of pump and motor, the valve plate specifically designed for pump or motor may not be suitable for a secondary unit. This paper mainly discusses design of valve plate of secondary unit applied in mobile crane, several critical points needed to be noticed during design have been discussed, furthermore, by adopting the proposed method to optimize a valve plate, which originates from closed-loop pump and now is used in opened-loop system, noise reduction was realized. Firstly, 1D simulation models, including pump condition and motor condition, were established in AMESim to obtain cylinder pressure, flow ripple and other critical parameters; secondly, by using Pumplinx, 3D numerical simulation was conducted to evaluate the cavitation risk; finally, a test bed was set up to validate the simulation result. Simulation result agreed well with the tested one. Both of them verified practicability of the proposed method. This research may provide a guidance for engineers and scholars who are interested in pump and motor. [ABSTRACT FROM AUTHOR]

This study is aimed at investigating the growth rate of azimuthal perturbation modes in an ideal annular linear induction pump model. The positive growth rate of azimuthal perturbation modes is associated with the unstable behaviour of the annular linear induction pump and is known in the literature as MHD instability characterized by strong low-frequency oscillations of magnetic field, flowrate, and pressure. A linear stability analysis of a height-averaged quasistationary main flow in the ideal annular linear induction pump has been conducted, where only temporally evolving azimuthal modes of the axial velocity and magnetic field perturbations were considered. The obtained results predict damped or damped oscillating perturbations in a stable regime as a function of Rm, Rms, N and κm. In the studied parameter range, an amplification of perturbations without oscillations was observed above the instability threshold. It can be concluded that the analysed model of the ideal annular linear induction pump cannot predict experimentally and numerically the observed low frequency oscillations. [ABSTRACT FROM AUTHOR]

The objective of the present study is to develop a numerical model of the centrifugal electromagnetic induction pump to predict the developed pressure in the case of zero flowrate. This is done using the COMSOL Multiphysics software in a 2D space with a time harmonic approach. A good agreement with previously reported experimental results was obtained. Based on the developed model, a study of the linear electromagnetic induction pump is also carried out and the obtained results are compared with those for the centrifugal electromagnetic induction pump. It is shown that with a low interaction parameter, the centrifugal pump can develop a significantly higher pressure than the linear pump. [ABSTRACT FROM AUTHOR]

The study of hydrodynamic instability in the safety systems of nuclear power plants is relevant. In the deterministic analysis of the safety of nuclear power plants based on accident simulation, it is necessary to take into account the possibility of hydrodynamic instability in the operational and transient modes of safety systems. The consequences of the emergence of hydrodynamic instability in safety systems can be following: a significant deterioration of the heat and mass exchange conditions in the reactor and steam generators during the heating process, an increased power of thermo-hydro-shock on the equipment of the nuclear installation and other negative effects. The negative consequences of the hydrodynamic instability in the safety systems of nuclear power plants can be a significant deterioration in the conditions of heat-mass exchange and the thermal water hammers with increased power. The main reasons for the hydrodynamic instability in safety systems are inertial lag in the response of control valves and head-flow characteristic of pumps to “fast” changes in hydrodynamic parameters in nuclear power plant systems. The purpose of this work is to determine methods for minimizing the impact of the causes of hydrodynamic instability in security systems. The methods of substantiating effective structural and technical parameters of damping devices to prevent conditions of hydrodynamic instability in stationary working and transient modes of safety systems with pumps are given. A method for substantiating effective design and technical parameters of damping devices to prevent conditions of hydrodynamic instability in transient modes of starting pumps of safety systems is presented. Stability conditions in stationary operating modes of the initial steam-gas volume of damping devices are determined. The minimum permissible dimensions of damping devices that meet the conditions of hydrodynamic stability in the transient modes of SB pumps are determined. [ABSTRACT FROM AUTHOR]

To increase the service coverage, Perumda Tirta Pakuan Kota Bogor needed to reduce operational costs. An important part of operational costs was energy costs, so it was necessary to reduce energy consumption. Based on Perumda Tirta Pakuan electricity bill, the largest energy consumption in the distribution system was Intan Pakuan service area. The cost of electricity consumption for Intan Pakuan pump house in 2020 is Rp. 211.786.451. Therefore, it was necessary to analyze the performance of the pump so that the pump/s energy consumption can be known and recommendations for improvements that can improve service and energy savings can be made. Measurements were made on the pump energy consumption and pump electrical parameters. In addition, measurements of fluctuations in water flow at the pump discharge were carried out. Based on the results of data processing, the pump efficiency at peak hours was 38.41%, while at minimum hours was 21.68%, and the pump efficiency based on the average energy consumptions and water distribution was 31.6%. Recommendations for improvement that can be done was to replace the pump according to usage needs. After calculation with the recommended pump, it was found that the pump efficiency increased to 74.52% and there was a savings in electricity consumption costs of Rp. 842.089 per month. [ABSTRACT FROM AUTHOR]

Based on the performance assessment in 2020, Perumda Air Minum Tirta Kahuripan apparently has spent more energy costs compared to the average municipal waterworks in Indonesia. The largest energy cost in water supply and distribution system is commonly allocated for the pumping system. Among all the pumps at the Perumda Air Minum Tirta Kahuripan, the distribution pumps for Kaum Pandak line have been working for a long time - more than five years. After measuring for three days, it was found that the value of Specific Energy Consumption (SEC) for both pump 1 and 2 were 0.40 kWh/m³ and the performance efficiency of both pumps were below 50%, which was 44.38% for pump 1 and 43.02% for pump 2. An energy saving plan was prepared by replacing the pumps which may save 2,198.18 kWh per month or worth Rp. 2,498,301,36 in one month. [ABSTRACT FROM AUTHOR]

Work on the modernization of irrigation pumping stations in our Republic has a great relevance. Technical modernization and reconstruction of pumping stations require a reliable scientifically based methodological approach. Each pumping station regularly keeps records and controls the operation of equipment and facilities. These data in processed form can be applied in the modernization of irrigation pumping stations. On the example of the analysis of the reliability characteristics of the Kiziltepa 2 pumping station (Uzbekistan), a methodology has been developed to justify the modernization and the order of replacement of the main equipment. Comparison of the results of calculation of quantitative parameters (criteria) of reliability of pumping station equipment with the data of field tests of aggregates showed that they can diverge. Therefore, the operational reliability assessment should be carried out comprehensively, and not only the results of a full-scale survey should be taken into account, but also the quantitative parameters of the reliability of the pumping station calculated according to previous years of operation. The use of this technique will make it possible to dispense with complex tests to assess the residual life of equipment parts by destructive testing methods.

Stomata in the plant epidermis open in response to light and regulate CO2 uptake for photosynthesis and transpiration for uptake of water and nutrients from roots. Light-induced stomatal opening is mediated by activation of the plasma membrane (PM) H+-ATPase in guard cells. Overexpression of PM H+-ATPase in guard cells promotes light-induced stomatal opening, enhancing photosynthesis and growth in Arabidopsis thaliana. In this study, transgenic hybrid aspens overexpressing Arabidopsis PM H+-ATPase (AHA2) in guard cells under the strong guard cell promoter Arabidopsis GC1 (AtGC1) showed enhanced light-induced stomatal opening, photosynthesis, and growth. First, we confirmed that AtGC1 induces GUS expression specifically in guard cells in hybrid aspens. Thus, we produced AtGC1::AHA2 transgenic hybrid aspens and confirmed expression of AHA2 in AtGC1::AHA2 transgenic plants. In addition, AtGC1::AHA2 transgenic plants showed a higher PM H+-ATPase protein level in guard cells. Analysis using a gas exchange system revealed that transpiration and the photosynthetic rate were significantly increased in AtGC1::AHA2 transgenic aspen plants. AtGC1::AHA2 transgenic plants showed a>20% higher stem elongation rate than the wild type (WT). Therefore, overexpression of PM H+-ATPase in guard cells promotes the growth of perennial woody plants.

Stomata in the plant epidermis open in response to light and regulate CO2 uptake for photosynthesis and transpiration for uptake of water and nutrients from roots. Light-induced stomatal opening is mediated by activation of the plasma membrane (PM) H+-ATPase in guard cells. Overexpression of PM H+-ATPase in guard cells promotes light-induced stomatal opening, enhancing photosynthesis and growth in Arabidopsis thaliana. In this study, transgenic hybrid aspens overexpressing Arabidopsis PM H+-ATPase (AHA2) in guard cells under the strong guard cell promoter Arabidopsis GC1 (AtGC1) showed enhanced light-induced stomatal opening, photosynthesis, and growth. First, we confirmed that AtGC1 induces GUS expression specifically in guard cells in hybrid aspens. Thus, we produced AtGC1::AHA2 transgenic hybrid aspens and confirmed expression of AHA2 in AtGC1::AHA2 transgenic plants. In addition, AtGC1::AHA2 transgenic plants showed a higher PM H+-ATPase protein level in guard cells. Analysis using a gas exchange system revealed that transpiration and the photosynthetic rate were significantly increased in AtGC1::AHA2 transgenic aspen plants. AtGC1::AHA2 transgenic plants showed a>20% higher stem elongation rate than the wild type (WT). Therefore, overexpression of PM H+-ATPase in guard cells promotes the growth of perennial woody plants. [ABSTRACT FROM AUTHOR]

The quality characteristics of raw water sources in the regional integrated drinking water supply system (SPAM) of Banjarbakula were investigated and found to maintain the supply of drinking water quantity and quality in accordance with drinking water standards. The optimum model for the mixing process of raw water and poly aluminum chloride (PAC) and pump stroke for the input of water sources from rivers to obtain a composition setting that is in accordance with the raw water sources of each region in the region was selected and determined. So the optimum parameter setting model between alum water, raw water and pump stroke for each raw water source is known and is regionally integrated as a result of a comprehensive study. The integration of Taguchi parameter design and response surface can complement each other and become two methods that go hand in hand in the process of optimizing clean water products. Parameter design provides a very practical optimization step, the basis for this formation refers to the factorial fractional experimental design. However, the absence of statistical assumptions that follow the stages of analysis makes this method widely chosen by researchers and practitioners. With the experimental design of the raw water mixing process, turbidity such as 5 lt/sec, 10 lt/sec, 15 lt/sec, 20 lt/sec and 25 lt/sec and % PAC concentration 5 ppm, 10 ppm, 15 ppm, 20 ppm and 25 ppm with a pump installation stroke of 5 %, 10 %, 15 %, 20 % and 25 % were used. In the process of adding PAC, always pay attention and observe the behavior of the attractive force of the floating particles (flock). The particles were then subjected to SEM (scanning electron microscopy) to determine the dimensions of the flock grains deposited [ABSTRACT FROM AUTHOR]

A limaçon machine is a rotary positive displacement device, in which the housing and rotor are constructed of limaçon of Pascal curves. Previous works have been published to investigate the working of these machines in two applications: gas expanders and compressors. This article presents a theoretical investigation into the potential of modifying the rotor profile of the limaçon machines to simplify the machine's manufacturing process and to reduce production cost. The proposed modification will produce new characteristics for the housing-rotor interaction. An outcome that motivates the need to obtain new mathematical models to investigate the housing-rotor interference and describe the volumetric relationship of the new machine. This article also employs an optimization approach to design the best machine for a given set of operating conditions, i.e., expander, compressor, and pump. The outcome of this study confirms the validity of the proposed modification and its potential to produce a limaçon machine with favorable characteristics. [ABSTRACT FROM AUTHOR]

Purpose: Vibration is a major issue in turbomachines which causes damage to them and leads to reduction in life and efficiency. This paper reviews various methods to measure the amount of vibration in various turbomachines and also discusses various reasons for the same. This will significantly assist in articulating these vibrations. Procedure: This paper lists various experiments done, causes, factors, comparison of different turbomachines and their results. Turbomachines which are taken into consideration are Francis turbine, radial turbines, axial turbines, compressors, pumps and fans. Result: The outcome elucidates the changes in vibrations as a function of different input parameters. Conclusion: It can be concluded through various experiments on different types of turbomachines that the major causes of vibrations are cavitation and resonance while excess speed and longer operating periods too contribute to them. [ABSTRACT FROM AUTHOR]

Load sensing (LS) is a dominant fluid power actuation technology in mobile machines, particularly in construction and agriculture. It has the advantage of guaranteeing good controllability in systems with multiple actuators while promoting higher energy efficiency. Several variants of LS systems have been proposed over the years, and research on cost-effective methods to further increase their efficiency is still of interest for original equipment manufacturers (OEMs) and the fluid power community. This article presents two solution, referred to as variable pump margin (VPM) and hybrid variable margin (HVM), suitable to improve the energy efficiency in pre-compensated LS systems such as those used in agricultural tractors. Both methods allow either downsizing the control valves or reducing the power consumption over the working range. Compared to a standard LS system, the VPM solution lowers the pump pressure using an electronic proportional pressure-reducing valve (ep-PRV), while the HVM solution uses a second ep-PRV in the compensator’s pilot line to further minimize the pressure differential across the LS valve. Simulation and experimental results show that, among the main working conditions, the VPM solution on average achieved 6.7% power saving over the standard LS system, while the model predicted an average improvement of 15.6% for the HVM solution. [ABSTRACT FROM AUTHOR]

A widespread use of wind turbines can fully or partly provide energy for the consumers, but with due regards to certain investments and instability of energy generation. Technologies of using wind energy imply the conversion of the mechanical energy of a wind flow into the electrical or heat energy. The work is concerned with the estimation of the amount of heat in the process of heating liquid coolants and heat-transfer fluids when using wind mechanical plants. In the paper was made a numerical analysis of the temperature rise of the liquid which circulates in a closed loop of a gear-type pump, whose productivity is 3 l/m and which is driven by a wind turbine 5 kW of power capacity under a nominal wind speed of 7 m/s and under cycle duration of 2 s. The analysis showed that the temperature increased by 0.290 °К/s. If such wind speed is observed during one hour, the temperature of 100 kg of water will increase by 8.1°С. Heating of a heat-transfer fluid with a supply of mechanical energy to a working part can be achieved by a centrifugal fan. Assuming that the given process occurs without supplying and removing heat energy (it is adiabatic), for the capacity of 1.5 kW and under the revolution in a range of 1000....3000 r/m, the changes in temperature will range from 0.38 to 0.87 °К/s, but for the capacity of 7.5 kW and under 750 - 1500 r/m, the changes in temperature will range from 0.56 to 1.23 °К/s. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Flywheel is an important component for the canned motor reactor coolant pump (RCP). The flywheel of horizontal canned motor reactor coolant pump (HRCP) is different from RCP's flywheel. Its clearance width or different thermal conductivity structure would affect the flow structure of flywheel clearance flow, and then affect temperature distribution of the clearance, which would further affects the life and stability of flywheel. Therefore, it is necessary to analyze the flow and heat transfer characteristics of flywheel clearance flow in detail. This paper applies a Detached Eddy Simulation (DES) method to study the flywheel clearance flow of HRCP. The results show that the DES method can capture the small-scale vortex structure in turbulence Taylor-Couette flow and then give a more refined flow field morphology. The authors further study the regularity of flywheel clearance flow with different thermal conductivity structure, and the results indicate that optimizing thermal conductivity structure can effectively reduce flywheel's temperature. The authors also investigate the heat dissipation mechanism of different flywheel clearance structures. [ABSTRACT FROM AUTHOR]

• A novel simulation method is proposed to identify the causes of lubrication failure in high-speed coolant pumps for electric vehicles. • Experimental validation confirms the accuracy of simulations for both the pump and bearing. • The steady radial forces of the pump rotor are effectively balanced by the bearing load capacity. • The rotor–stator interaction results in unsteady radial forces, inducing substantial whirl in the bearing. • The bearing whirl reduces lubricant film pressure gradient and load capacity, ultimately leading to lubrication failure. The high-speed coolant pump is essential for electric vehicle thermal management, ensuring optimal module temperatures. The pump impeller and bearing are combined into a rotor and then fit on a fixed shaft with a clearance, aiming to generate a complete lubricant film between the stationary journal and rotating bearing during pump operations. However, during the pump durability test under off-design conditions, severe wear occurred on both the journal and bearing. A novel simulation method based on computational fluid dynamics and dynamic mesh is developed to investigate the lubrication failure. User-defined functions are programmed to articulate the simultaneous rotation and whirl of the bearing, and the effects of temperature and cavitation are considered. Both the pump and bearing simulations closely align with experimental results. When the radial force of the pump rotor is steady, the bearing only rotates without whirling, and the bearing load capacity can counteract the maximum radial force of the rotor. However, the rotor experiences fluctuating radial forces over time, primarily attributed to elevated pressure levels at the volute tongue caused by the rotor–stator interaction. This phenomenon results in the bearing to rotate and whirl simultaneously. The load capacity generated by the backward whirl of the bearing is greater than that of the forward whirl. Nevertheless, the bearing whirl initiates a decline in the extremum values of lubricant film pressure. Subsequently, both load capacity and minimum film thickness exhibit a continuous decrease, eventually culminating in the breakdown of the complete lubricant film and resulting in contact wear failure. These new findings contribute to proposing measures to reduce wear under unsteady excitations. [ABSTRACT FROM AUTHOR]

This paper presents theoretical considerations and working parameters analyzes of hydrotransport during unstable flow. The variable flow of hydraulic mixture in installations causes unsteady operation and pipes spraying, pump damage, obturation in various sections of the pipeline, reduced capacity as well as higher operating costs. Using mathematical equations presented in this paper, such parameters of the hydraulic mixture, hydrotransport installation and control devices can be determined which protect system from possible clogging. Considering the fact that critical speed of hydraulic mixture depends on transported material grain size, mixture volume mass, diameter of pipeline and specific gravity of solid phase, it is possible to accurately analyze obturation in hydrotransport installations depending on those parameters. In order to prevent hydraulic impacts in hydrotransport installation pipelines, which value can be determined mathematically, it is necessary to adjust installation to hydromixture parameters and pump, or vice versa.

Background: The heart pump allows blood to flow where the network of arteries, capillaries, and veins throughout the body regulates the rate of circulation of the blood. Parameters that determine the fitness level of the cardiovascular system include heart rate (HR), blood pressure (BP), VO2 max, fatigue, etc., The calf muscle pump is the most important of the lower limb, as it is the most efficient and has the largest capacitance. It has been suggested that increased leg strength, independent of cardiovascular training, may augment an aerobic endurance performance. Aim: The aim of this study is to determine the effect of strength training of gastrocnemius and soleus muscles on cardiovascular parameters. Materials and Methods: An experimental study carried out at MRIIRS Institution for 1 year. Forty-five recreational players aged between 20 and 30 years were selected after obtaining informed consent. Participants were divided equally into three groups by a convenient chit method. They were assessed for cardiovascular parameters of HR, BP, VO2 max, fatigue, and FI at baseline and after 8 weeks training program. Group A participated in gastrocnemius and soleus; Group B participated in gastrocnemius, and Group C participated in the soleus muscle training program. Results: Paired t-test for pre–post training shows a significant difference P < 0.05 for all the groups. ANOVA used between groups pre–post training were found to be significant for HR and systolic BP (SBP), and nonsignificant for diastolic BP (DBP) and VO2 max. Kruskal–Wallis test used between groups before and after training was found to be significant for fatigue and fitness index (FI). Jonckheere-trend test Post hoc analysis showed that Group A performed better than Group C and B. Wilcoxon signed-rank test for fatigue and FI showed a significant difference for all the groups. Conclusion: Eight weeks of leg muscle training on cardiovascular parameters have an effect on cardiovascular parameters of HR, SBP, FI, and fatigue. The results showed no significant effects on DBP and VO2 max.

Project Description:  Anteater and Associates has been contracted by HDR Engineering Inc. to construct a two-phase wastewater pump station for a residential community in Hesperia, California.  Project Goal: The project goal is to develop a pump station that will accommodate for an increase in wastewater production from a new residential track of homes that will some be built in the area.  The pump station will be implemented in tow-phases to ensure that as the residential communities grow the station will be able to handle the increased loading on the system.  Advisor: Brett Sanders

Using the Fault Tree Analysis method - FTA, an analysis of the potential failure modes of the elements of the crop sprayer pump Comet BP 105 was carried out in this paper. In order to conduct a detailed analysis of the causes and failure modes of a pump, it is necessary to know the structure, the way of operating and the interrelationship of the constituent elements. Based on the collected data, the fault tree of the considered object was formed. In this way, the cause-and-effect relationship between failures of structural entities of different levels of affiliation is established. In conclusion of the paper, the importance of applying the fault tree analysis to improve the efficiency of the existing systems and the quality in the development of similar design solutions is pointed out.

Abstract Energy production from renewable sources offers an efficient alternative non-polluting and sustainable solution. Among renewable energies, solar energy represents the most important source, the most efficient and the least expensive compared to other renewable sources. Electric power generation systems from the sun’s energy typically characterized by their low efficiency. However, it is known that photovoltaic pumping systems are the most economical solution especially in rural areas. This work deals with the modeling and the vector control of a solar photovoltaic (PV) pumping system. The main objective of this study is to improve optimization techniques that maximize the overall efficiency of the pumping system. In order to optimize their energy efficiency whatever, the weather conditions, we inserted between the inverter and the photovoltaic generator (GPV) a maximum power point adapter known as Maximum Power Point Tracking (MPPT). Among the various MPPT techniques presented in the literature, we adopted the adaptive neuro-fuzzy controller (ANFIS). In addition, the performance of the sliding vector control associated with the neural network was developed and evaluated. Finally, simulation work under Matlab / Simulink was achieved to examine the performance of a photovoltaic conversion chain intended for pumping and to verify the effectiveness of the speed control under various instructions applied to the system. According to the study, we have done on the improvement of sliding mode control with neural network. Note that the sliding-neuron control provides better results compared to other techniques in terms of improved chattering phenomenon and less deviation from its reference.

The article aims at defining and analysing the energy loss coefficients in design solutions of rotating displacement machines, with a piston machine as an example. The energy losses observed in these machines include mechanical loss, volumetric loss, and pressure loss. The scale and relations between these losses in different machines depend on machine design and manufacturing quality, and on operating parameters. The operating parameters, in turn, which affect directly or indirectly the above losses depend on whether the machine works in pump or hydraulic motor regime. The article is also a contribution to the development of a library of ki coefficients which define the losses in displacement machines, as the knowledge about these coefficients makes it possible to assess fast and easily the energy efficiency of a machine or drive system at each point of its working area.

This article describes the importance of water hydraulic components and systems from the aspect of quality of life. Water hydraulics has become of major interest because it is human friendly andenvironmentally safe. The continuous introduction of new materials and technologies in the production of components and systems of water hydraulics ensures the increasing application of these systems.The most important component of a water hydraulic system is the pump. Research of piston axial water hydraulic pumps is presented in this paper. A test standwas developed to validate the computational fluid dynamics simulations for the water hydraulic axial piston pump.

A clean and healthy environment must be an increasing priority. Different kinds of hydraulic fluids are in use nowadays. Unfortunately, the majority of them are harmful. The use of tap water as a hydraulicpressure medium is one of the possible solutions. This study presents the research and development of different hydraulics components. Every research of a new water-hydraulic component starts with basic tribological investigations of different material pairs and their surfaces. Then follows the design and calculations of the hydraulics characteristics, the production of a prototype and its experimental investigations. The following water-hydraulic components, i.e., proportional control valve, hydraulic cylinder, piston pump, hydraulic accumulator, check valve and hydraulic motor, will be presented.

Digital twins technology (DTT) is an application framework with breakthrough rules. With the deep integration of the virtual information world and physical space, it becomes the basis for realizing intelligent machining production lines, which is of great significance to intelligent processing in industrial manufacturing. This review aims to study the application of DTT and the Metaverse in fluid machinery in the past 5 years by summarizing the application status of pumps and fans in fluid machinery from the perspective of DTT and the Metaverse through the collection, classification, and summary of relevant literature in the past 5 years. The research found that in addition to relatively mature applications in intelligent manufacturing, DTT and Metaverse technologies play a critical role in the development of new pump products and technologies and are widely used in numerical simulation and fault detection in fluid machinery for various pumps and other fields. Among fan-type fluid machinery, twin fans can comprehensively use technologies, such as perception, calculation, modeling, and deep learning, to provide efficient smart solutions for fan operation detection, power generation visualization, production monitoring, and operation monitoring. Still, there are some limitations. For example, real-time and accuracy cannot fully meet the requirements in the mechanical environment with high-precision requirements. However, there are also some solutions that have achieved good results. For instance, it is possible to achieve significant noise reduction and better aerodynamic performance of the axial fan by improving the sawtooth parameters of the fan and rearranging the sawtooth area. However, there are few application cases of the Metaverse in fluid machinery. The cases are limited to operating real equipment from a virtual environment and require the combination of virtual reality and DTT. The application effect still needs further verification.

Common-rail fuel injection systems are still a good option for equipping new car models. The technology is well known, systems of this type are reliable and can be used on a wide variety of diesel and petrol engines. However, there is still room for improvement. The ball check valve, which is part of the common-rail pump, is designed to open and allow the compressed fluid to be sent to the high-pressure accumulator and close to not allow fuel to return to the compression chamber. The valves’ design directly influences the volumetric efficiency of the outlet flow and the robustness against high pressures that lead to low performance and short service life of the fuel injection systems. This paper aims to compare two ball check valves with conical and spherical seat designs. The analysis is based on theoretical calculations and CFD simulations, which will give more confidence in the results. Considering the comparative analysis results, the ball check valve with a spherical seat shows better flow dynamics than the ball check valve with a conical seat. In addition to the improved flow dynamics, the ball check valve with spherical seat seems to have a uniformly distributed fluid pressure inside the valve. In contrast, the conical seat ball check valve has high local fluid pressures, leading to fatigue.

Despite their widespread use in the chemical industries, hydrogenation reactions remain challenging. Indeed, the nature of reagents and catalysts induce intrinsic safety challenges, in addition to demanding process development involving a 3-phase system. Here, to address common issues, we describe a successful process intensification study using a meso-scale flow reactor applied to a hydrogenation reaction of ethyl cinnamate at kilo lab scale with heterogeneous catalysis. This method relies on the continuous pumping of a catalyst slurry, delivering fresh catalyst through a structured flow reactor in a continuous fashion and a throughput up to 54.7 g/h, complete conversion and yields up to 99%. This article describes the screening of equipment, reactions conditions and uses statistical analysis methods (Monte Carlo/DoE) to improve the system further and to draw conclusions on the key influential parameters (temperature and residence time).

A new robust adaptive hybrid second-order generalized integrator (SOGI) based rotor flux observer (RFO) for self-sensing control of solar photovoltaic array fed permanent magnet synchronous motor drive for water pump is developed in this article. The conventional pure integrator based RFO introduces dc offset, saturation, and harmonics, whereas a low-pass filter based produces attenuation and phase delay. To overcome these problems, a new n-layer hybrid SOGI structure (HSS) is developed and its four-layer version is used in the system. An adaptive frequency tracker is then integrated with four-layer HSS to track wide variations in system frequency due to dynamic solar irradiations, which results in an adaptive hybrid SOGI (AHS) structure. However, the AHS is sensitive to system parametric uncertainties. Thus, the sliding mode approach is used to impart the robustness. This results in new robust AHS (RAHS) structure for accurate observation of rotor flux. The improved performance of developed RAHS over its conventional counterparts is proved through Bode curves and flux loci while test results validate its performance. [ABSTRACT FROM AUTHOR]

The transmission path of vibration difficult to determine has posed a great threat to the safe operation of water transmission pipeline, due mainly to the complex structure of pump station pipeline, where there are many vibration sources. In this study, an attempt was made to analyze the pipeline transfer path characteristics of pumping stations using transfer entropy. The pipeline of 7 pump stations in an irrigation area was also taken as the research object. Firstly, a prototype test was carried out to obtain the spectrum diagram, and energy proportion, thereby analyzing the main vibration source of pipeline vibration. Then, a transmission entropy method was used to identify the vibration transmission path of the main vibration source in the pump station pipeline under various working conditions. The effectiveness of the pipeline vibration transmission path was finally verified when taking the information transmission rate as the quantitative standard. The results show that: 1) The main vibration source was caused by the blade frequency and frequency doubling in the pipeline, mainly transmitting from the elbow and tee pipe to other parts when the pumping station unit operated stably. Furthermore, the average information transmission rate was 27.2%. More importantly, the transmission rate was relatively low during stable operation, mainly because the anchor block, buttress, and other devices played a critical role in the vibration reduction and energy dissipation. 2) The main vibration source was also caused by the blade frequency in the pipeline, mainly transmitted from the elbow and tee to other parts of the pipeline, when the pump station unit starting up. The average information transmission rate was 42%. It was found that a large part of the energy at the elbow and tee was transmitted to other parts of the pipeline during startup. 3) The main vibration source was the high-frequency vibration caused by low-frequency water flow pulsation and pipe water coupling in the pipeline when the pump station unit was shut down. The vibration was mainly transmitted periodically between the valve, elbow, and tee. The average information transmission rate was 51.4%. It can be seen that a large part of the energy from the valve, elbow, and tee was transmitted to other parts of the pipeline. Correspondingly, the information transmission rate of each working condition showed that a large part of vibration energy at the pipeline valve, elbow, and tee pipe was still transmitted to other parts. Whether the machine was switched on or off, the energy transmitted by the pipeline during the stable operation was less under the control of vibration reduction measures, such as anchor block. Therefore, the prototype observation data was selected to analyze the source of vibration through the spectrum diagram and energy proportion, where quantitatively determine the transmission relationship between vibration from the perspective of energy with the help of transmission entropy and information transmission rate, as well as the direction of vibration transmission. It was more efficient and intuitive than before, indicating great advantages in the application of vibration transmission path recognition. Consequently, this research can greatly contribute to accurately identify the vibration transmission path of the main vibration source in the pump station pipeline, thereby identifying the dangerous parts of the pipeline under different working conditions, where the vibration reduction measures can be further proposed. This finding can provide a promising theoretical basis for the operation and management of the pump station pipeline [ABSTRACT FROM AUTHOR]

Hydraulic drive systems play a vital and significant role in the mining and construction equipment. It gives a smooth change in the output speed, torque, and power of the machine.. Regulation of the displacements of the pump and the hydro-motor of the drive facilitates the control of the straight running and steering of the machines. The present study deals with the performance analysis of hydrostatic drive similar to that is incorporated in an SDL machine. It consists of a variable displacement pump rotated by a constant speed electric motor and a variable displacement hydro-motor. They are connected in the closed-circuit configuration. The present study investigates the performances of the hydrostatic drive used in the SDL machine through detailed modelling and experimentations. The study finds a reasonable efficiency zone for the design guideline to operate the hydrostatic drive. The effect of perturbation of critical system parameters on the dynamic performance of the drive has been also studied through simulation of the developed model. The outcome of the present work should be expedient for the preliminary design and assortment of similar hydraulic drive used in the mobile, mining equipment. [ABSTRACT FROM AUTHOR]

An algorithm is proposed for calculating a closed hydraulic system consisting of a pump and a hydraulic motor. As an example, the hydraulic system of a wind turbine is considered. The calculation is based on the method used for the hydraulic system of mobile machines. The basic characteristics of the system components are analyzed. Factors of importance in selecting the initial data for the calculation, the working fluid, and the diameter of the hydraulic lines are identified. [ABSTRACT FROM AUTHOR]

In the paper the theoretical basis of pumped-storage power plant operation is presented. Working conditions of hydraulic machines in these kinds of objects are described and examples are given. The Czech research results as well as German theoretical analyses on the topic of water energy storage in underground mines are characterized. The conditions for building pumped-storage power plant in Polish underground coal mines, including liquidated ones, are determined. Analysis of parallel operation of multistage centrifugal pumps, dedicated to the mine drainage system, manufactured and operated commonly in Poland is presented. The main dimensions calculations of two multistage centrifugal pumps (power of 10 MW and 25 MW), dedicated for selected parameters, are presented. [ABSTRACT FROM AUTHOR]

Fountains have been a constant in the life of men, from the oldest civilizations to the present day. The first fountains allowed access to the water that nature offers spontaneously, to meet man and domestic animals' basic needs. Then the first artifi- cial fountains arrived, built in villages, towns and cities, which for many years provided their inhabitants with the water they required, also serving as a meeting place and recreation. After them ornamental artificial fountains arrived, which were built in streets, squares and parks and in the inside of palaces and gardens, and served as an urban element that contributed to organise the landscape, softening and embellishing the environment. They can also be considered as a work of art, acquiring the purpose of artistic expression with their sculptures and architectural fountains, leaving the water that gushes from their fountains or falls through the waterfalls as a secondary ornament. The use of water as an element of architectural and urban composition has been present in all cultures and the fountain has been the most common modality. Its evolution is the result of man's use and behaviour with water, which since its inception has been conditioned by the technological level reached in each era. The article takes a quick tour through the history of fountains, from their origin to the present day. [ABSTRACT FROM AUTHOR]

The conventional method of conducting laboratory experiments in engineering becomes a serious challenge asa result of the COVID-19 pandemic; the development of a virtual laboratory is considered a suitable substitute to real laboratory. In this work, a virtual laboratory for a family of centrifugal pumps has been developed. Cavitation development within the centrifugal pumps and the pumps performances in pipeline networks were studied. Negative potential head and high fluid temperature increased early cavitation incidence, while low fluid temperature, as well as positive potential head reduced it. The choice of pipe diameter and its roughness factor played significant roles in the pumps' performance. The study shows that virtual laboratory represents a good training environment that enables precise pipeline and pump flow matching. [ABSTRACT FROM AUTHOR]

The effect of gas desorption from the solution with nucleation of gas bubbles is a process that allows to improve fuel atomization in diesel engines. The advantage of such a process, which has been experimentally proven, is a significant reduction in harmful emissions. The conducted research highlighted one of the fundamental problems. This problem concerned the injection pump - it was necessary to design a new construction that would be adapted to the desorption effect. The authors of the work proposed a construction based on a hypocycloidal drive. Due to the nature of the process, i.e. the use of exhaust gases dissolved in diesel fuel, it was very important to analyze the volumetric losses of the compression process - this is the main goal of this article. The authors proved that for the adopted design assumptions, the power of volumetric losses resulting from compressibility is 0.25% of the power consumed by the pump. [ABSTRACT FROM AUTHOR]

We have developed a hydrogen (H 2) refueling solution capable of delivering precooled, compressed gaseous hydrogen for heavy duty vehicle (HDV) refueling applications. The system uses a submerged pump to deliver pressurized liquid H 2 from a cryogenic storage tank to a dispensing control loop that vaporizes the liquid and adjusts the pressure and temperature of the resulting gas to enable refueling at 35 MPa and temperatures as low as −40 °C. A full-scale mobile refueler was fabricated and tested over a 6-month campaign to validate its performance. We report results from tests involving a total of 9000 kg of liquid H 2 pumped and 1350 filling cycles over a range of conditions. Notably, the system was able to repeatably complete multiple, back-to-back 30 kg filling cycles in under 6 min each, in full compliance with the SAE J2601-2 standard, demonstrating its potential for rapid-throughput HDV refueling applications. [Display omitted] • A liquid H 2 pump-enabled solution for 35 MPa hydrogen refueling has been developed. • Results from field testing of a full-scale mobile trailer system are reported. • Pump performance: 40 MPa outlet pressure; up to 285 kg/h; 43,000 pump strokes. • System performance: 1350 J2601-2 compliant fill cycles, including back-to-back fills. [ABSTRACT FROM AUTHOR]

In summer, the utilization of solar energy can possibly satisfy the water demand. This paper examines the fluid flow in solar pump systems with solar cells. Specifically, a solar pump system model was designed and subjected to an installation test. The model consists of two solar cell units connected in series, which generate electricity and flow into the pump system. By the principles of fluid mechanics, the test results were analyzed to optimize the pump efficiency. The analysis shows that the solar cell efficiency is influenced by solar intensity, while the pump loss is maximized by fluid friction. In addition, pressure increase could affect the time of water filling; the voltage and current tend to be stable or constant. [ABSTRACT FROM AUTHOR]