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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. [ABSTRACT FROM AUTHOR]

Enabling minimally invasive and precise control of liquid release in dental implants is crucial for therapeutic functions such as delivering antibiotics to prevent biofilm formation, infusing stem cells to promote osseointegration, and administering other biomedicines. However, achieving controllable liquid cargo release in dental implants remains challenging due to the lack of wireless and miniaturized fluidic control mechanisms. Here wireless miniature pumps and valves that allow remote activation of liquid cargo delivery in dental implants, actuated and controlled by external magnetic fields (<65 mT), are reported. A magnet-screw mechanism in a fluidic channel to function as a piston pump, alongside a flexible magnetic valve designed to open and close the fluidic channel, is proposed. The mechanisms are showcased by storing and releasing of liquid up to 52 µL in a dental implant. The liquid cargos are delivered directly to the implant-bone interface, a region traditionally difficult to access. On-demand liquid delivery is further showed by a metal implant inside both dental phantoms and porcine jawbones. The mechanisms are promising for controllable liquid release after implant placement with minimal invasion, paving the way for implantable devices that enable long-term and targeted delivery of therapeutic agents in various bioengineering applications., (© 2024 The Author(s). Advanced Healthcare Materials published by Wiley‐VCH GmbH.)

【Objective】 Photovoltaic has been increasingly used to power irrigation systems in China, but optimizing its power output and operating load is an issue that is poorly understood. This paper aims to address this by taking sprinkler irrigation systems powered by photovoltaic as an example. 【Method】 The photovoltaic system used in this work was battery-free, and the experiment was conducted in a test rig in which the operation of the system under different nozzle numbers was measured and compared. 【Result】 ①Water pressure in the nozzles varied with light intensity, and the variation decreased as the duration of light intensity increased. The saturated light intensity under two loads was 300 W/m2, lower than that under four loads. ②With the increase in the number of sprinkler nozzles, the saturated working pressure in the nozzles decreases. The saturated water pressure in the sprinklers under two nozzles was about 450 kPa, and it reduced to 435 kPa when the nozzle numbers increased to four, indicating that the illumination intensity required to reach the saturated pressure in the sprinkler system increased as the number of nozzles increased. ③With the increases in sprinkler head numbers, the falling of water droplets in the radial direction and the difference in water droplets between the sprinkler sections both decreased. Water distribution under two nozzles was approximately trapezoidal, while under four nozzles the distribution became triangle from where the nozzles were to the far ends. ④The uniformity coefficient of the sprinkler irrigation system increased as the number of nozzles increased, and the maximum uniformity coefficient under four sprinkler nozzles was 2% larger than that under two nozzles. 【Conclusion】 Increasing the number of nozzles can increase the saturated light intensity of the system and reduced the saturated water pressure in the nozzles. The light-height of the pumps, rotational speed and flow rate all decreased as the light intensity transient amplitude increased. The pump flow, head curve and the pipeline characteristic curve move to the right of the intersection point, and the system running at fast flow condition can reduce nozzle pressure and improve sprinkler irrigation uniformity.

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.

Wear of end ring is to date an unreported and uninvestigated failure that very frequently takes place in deep-well submersible motor pumps. This article first analyses the particularities of these induction motors, especially their unusual rotor manufacturing process. Failure mechanism related to the end-ring wear is described, showing several examples of damaged rotors in a motor repair shop. Then, the difficulties of its diagnosis through conventional rotor asymmetry indicators are described, caused by the subtlety of this fault and the very easy appearance of false negatives. The end-ring wear detection through a multicomponent approach is researched through simulation, laboratory results, and the diagnosis of two-field motors showing that new fault alarm levels need to be defined. To perform this last step and for the first time in the technical literature, two induction motors working in a deep borehole have been continuously monitored (one measure every six operating hours) for almost one year. [ABSTRACT FROM AUTHOR]

The problem on the nonstationary pressure field formed in a filter bed with a well in the regimes of start of a pump used in the production of a fluid from the well, continuous work of the pump with a variable productive rate, and subsequent stop of the pump was solved with regard for the mass balance of the fluid flowing from the bed into the well, the fluid produced from the well, and the fluid used to change the fluid level in the annulus of the well. Results of computational experiments on determination of the spatial-temporal pressure distributions in the bed and in the well in different regimes of production of the fluid from the well are discussed. The main factors determining the spatial-temporal distributions of the pressure in the bed after the pumping of the fluid from the well begins and after it is terminated were found. The influence of the collector characteristics of the bed, the viscosity of the fluid saturating it, and the rate of pumping of the fluid from the well on the formation of pressure fields in the bed and in the well, the duration of the periods of relaxation and stabilization of the pressure field in the bed, and the dynamics of its transformation into the steady state at different stages of production of the fluid from the well was determined. [ABSTRACT FROM AUTHOR]

Receptor‐like kinases (RLKs) are a large group of plant‐specific transmembrane proteins mainly acting as receptors or co‐receptors of various extracellular signals. They usually turn extracellular signals into intracellular responses via altering gene expression profiles. However, recent studies confirmed that many RLKs can physically interact with diverse membrane‐localized transport proteins and regulate their activities for speedy responses in limited tissues or cells. In this minireview, we highlight recent discoveries regarding how RLKs can work with membrane transport proteins collaboratively and thereby trigger cellular responses in a precise and rapid manner. It is anticipated that such regulation broadly presents in plants and more examples will be gradually revealed when in‐depth analyses are conducted for the functions of RLKs. [ABSTRACT FROM AUTHOR]

This paper presents the results of FEM (Finite Element Method), CFD (Computational Fluid Dynamics) and modal analyses of model semi-axial pump. Two sets of impeller blades were printed by metal 3D printing technology with internal honeycomb structures. The set of solid blades, manufactured by CNC machining for a comparison, was also included. 3D printed blades were designed with internal structures in order to save material, and with respect to mechanical and dynamic properties. Saved material can change the starting moment, modulate modal properties or decrease strength properties. The 3D printed blades can be produced very quickly and with accurate blade surface finish. One of the reasons of this approach can be the use of 3D printed blades as spare parts for industrial applications or for model pump research. This paper contains short introduction to blade design with internal honeycomb structures and their one-way FSI analyses (Fluid Structure Interaction). The final results of best design are presented and discussed. [ABSTRACT FROM AUTHOR]

Although hydraulic pumps are frequently used in daily life, improper use due to oil analysis or oil contamination is ignored. There is no instantaneous inspection; instead, the oil is changed periodically at certain times, whether it is contaminated or not. Hydraulic systems operate based on Pascal's law, which states that the fluid will distribute the pressure equally to every point in a closed area. The fluid oil taken from an oil reservoir is moved into the pump by engine power. During this movement, as it passes through different pressure areas and different sections, undesirable events such as viscosity change and gas formation occur in the hydraulic oil. These formations collide with the outer walls and cause cavitation with respect to unwanted oil impurities. This cavitation causes unwanted vibration signals to occur in the normal working order of the system. As a result of cavitation, the particles that affect the lubricity and fluidity of the oil in the oil are mixed into the liquid and circulate freely. At the connection points, the blockage caused by the liquid in the pump cylinder block or the valve plate and the collisions of particles is effective. As a result, it creates vibrations of different frequencies. The frequency and amplitudes of these vibrations differ according to the degree of oil contamination. A method has been developed to find the degree of contamination of the oil circulating in the pump by looking at the amplitude and frequency of these vibrations measured from the motor body. There exist standards about the pollution of hydraulic fluid. With these standards, the maximum number of particles allowed for a given pollution level is defined. This topic is discussed in the conclusion to this study. This method has also been proven experimentally. Error and vibration analysis studies on pumps using a different approach are available in the literature. In these studies, pressure variation, total energy transmission, or artificial intelligence models were used to detect anomalies in the pump. In this study, the impurity rate of the oil was set at five different levels and the operating regime of the pump at each level was investigated experimentally. Rayleigh–Plesset and Zwart–Gerber–Belamri models, which are the most common cavitation models, were used to explain the bubble formation in the moving oil and the relationship of these bubbles with vibration. Frequency components were examined by the Discrete Fast Fourier Analysis method, where the operation of the pump was affected by the increase in oil impurity. [ABSTRACT FROM AUTHOR]

The first pump developed by Dr. Kadish and his team in 1963 aimed to "continue subcutaneous insulin infusion". The number of patients using insulin pumps has increased since the 1980s. This historical perspective has labeled pump therapy in endocrinology and metabolism synonymous with insulin pumps. However, certain other hormonal disorders might also benefit from this kind of treatment. Pump therapy is currently the best approach to achieve physiological mimicry. Furthermore, it may help in overcoming pharmacokinetic issues or allergies. Until now, hormone replacement via pumps has been a salvage method for complex cases at the expense of increased costs. However, it is believed that applications of pump treatment will widen in the future owing to the rapidly evolving technology. In this mini review, data on pump use for patients with adrenal insufficiency, hypogonadism, hypoparathyroidism, congenital adrenal hyperplasia, and congenital hyperinsulinism have been briefly summarized. The study has aimed at covering all the relevant clinical studies and important case reports/series. Methods: A systematic literature search has been conducted on PubMed database seeking articles published until May 2021 using a combination of the following Medical Subject Headings terms and keywords: pump "OR" continue infusion "AND" (adrenal insufficiency "OR" Addison "OR" hydrocortisone "OR" hypoparathyroidism "OR teriparatide" "OR" somatostatin "OR" hypogonadism "OR" hypoglycemia "OR" endocrinology "OR" hormone replacement). In addition, the reference publications in the identified articles have also been reviewed. [ABSTRACT FROM AUTHOR]

Miniaturized fluid manipulation systems are an important component of lab-on-a-chip platforms implemented in resourced-limited environments and point-of-care applications. This work aims to design, fabricate, and test a low-cost and battery-operated microfluidic diffuser/nozzle type pump to enable an alternative fluid manipulation solution for field applications. For this, CNC laser cutting and 3D printing are used to fabricate the fluidic unit and casing of the driving module of the system, respectively. This system only required 3.5-V input power and can generate flow rates up to 58 µL/min for water. In addition, this portable pump can manipulate higher viscosity fluids with kinematic viscosities up to 24 mPa·s resembling biological fluids such as sputum and saliva. The demonstrated system is a low-cost, battery-powered, and highly versatile fluid pump that can be adopted in various lab-on-a-chip applications for field deployment and remote applications. [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.

Piston pumps are widely used in the lubrication systems of mining machines. When carrying out technical maintenance (MOT), including lubrication and filling works, at the site of operation of mining machines due to the remoteness from repair shops and warehouses of fuels and lubricants (FAL), mobile repair shops (MRS), maintenance units (MU) and mechanized filling units (MFU) are used. The specificity of carrying out maintenance is to create conditions for the supply of oils, working fluids and lubricants to the corresponding systems of mining machines for their refueling. Existing piston pumps and pumping units, as a rule, are single-flow, and the piston is driven by a crank mechanism driven from the engine through a worm gear. The emergence of unique, hydraulic, low-mobility mining machines in open pit mining required a significant increase in the power of the MU and MFU oil pumping units, primarily for greases. However, the traditional design of the drive design of a crank-type piston pump unit at a power of over 80 kW does not allow achieving the specified operating time, it is accompanied by intensive wear of the drive elements and increased dynamics during operation. In addition, it is necessary to apply various designs of pumping units for the supply of liquid and grease lubricants. Thus, it is necessary to develop new circuit solutions for pumping units of the crank type, to improve mobile refueling facilities with a modernized design of the pump unit drive of the mobile lubrication and filling station MRS.

In this work, a couple of spur gears design was changed by two double- helical gears design with maintaining other parts in the same size approximately for a hydraulic pump of agricultural tractor. The main purpose of this attempt was to obtain a new hydraulic pump with better specifications and performance. The new elements of the pump were designed using 3D Solid Works software then the stresses analyses and CFD analyses were archived using ANSYS software. The results showed a better flow rate of the hydraulic fluid by about 17%. This reflects the success of this idea where the flow rate of the new design was much higher compared with spur gear pump. This will conclude that the new design led to improve the pump performance. Moreover, the new pump overcomes the problems that usually appear in spur gears such as noise, vibration fracture. However, this design considers one of the most difficult parts in manufacture process therefor, it was recommended to fabricate it with3D printers

The article is devoted to studying the contra-rotating stages with different impellers and blade discs. Determining the reduction of volumetric losses by modeling the contra-rotating stages in the software package ANSYS CFX. The work aimed to create and study the flow and characteristics: semi-open, closed impellers, and blade discs. As a result of the work, the following contra-rotating stages were determined and compared: the semi-opened impeller with the semi-opened blade disc; the closed impeller with the closed blade disc; the semi-opened impeller with the closed blade disc; the closed impeller with the semi-opened blade disc. As a result of research, fluid flows in contra-rotating stages and their characteristics in the form of pressure and efficiency were obtained. According to the obtained data, the expediency of using contra-rotating stages as a working body of the pump is written.

Through discrete element method-computational fluid dynamics, the internal flow field and particle motion law of a two-stage deep-sea lifting pump at different rotational speeds were analyzed in this work. In addition, the physical phenomena, such as flow field velocity, secondary flow, and particle flow, were studied. The relationship between the rotational speed of the lifting pump and solid–liquid two-phase flow was investigated. An experiment on the hydraulic performance of the lift pump showed that the resulting lift and efficiency were consistent with the numerical simulation data. When the rotational speed was 1,450 rpm, the particles can obtain a higher kinetic energy from the flow field, the flow was more stable, and particle deposition was reduced.

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]

Na+/K+ ATPase (NKA) comprises several subunits to provide isozyme heterogeneity in a tissue-specific manner. An abundance of NKA α, β, and FXYD1 subunits is well-described in human skeletal muscle, but not much is known about FXYD5 (dysadherin), a regulator of NKA and β1 subunit glycosylation, especially with regard to fibre-type specificity and influence of sex and exercise training. Here, we investigated muscle fibre-type specific adaptations in FXYD5 and glycosylated NKAβ1 to high-intensity interval training (HIIT), as well as sex differences in FXYD5 abundance. In nine young males (23.8 ± 2.5 years of age) (mean ± SD), 3 weekly sessions of HIIT for 6 weeks enhanced muscle endurance (220 ± 102 vs. 119 ± 99 s, p < 0.01) and lowered leg K+ release during intense knee-extensor exercise (0.5 ± 0.8 vs. 1.0 ± 0.8 mmol·min–1, p < 0.01) while also increasing cumulated leg K+ reuptake 0–3 min into recovery (2.1 ± 1.5 vs. 0.3 ± 0.9 mmol, p < 0.01). In type IIa muscle fibres, HIIT lowered FXYD5 abundance (p < 0.01) and increased the relative distribution of glycosylated NKAβ1 (p < 0.05). FXYD5 abundance in type IIa muscle fibres correlated inversely with the maximal oxygen consumption (r = –0.53, p < 0.05). NKAα2 and β1 subunit abundances did not change with HIIT. In muscle fibres from 30 trained males and females, we observed no sex (p = 0.87) or fibre type differences (p = 0.44) in FXYD5 abundance. Thus, HIIT downregulates FXYD5 and increases the distribution of glycosylated NKAβ1 in type IIa muscle fibres, which is likely independent of a change in the number of NKA complexes. These adaptations may contribute to counter exercise-related K+ shifts and enhance muscle performance during intense exercise.

Context: Hypoparathyroidism (hypoPTH) in adults is mainly due to total thyroidectomy. Conventional therapies (calcium, active vitamin D) can fail to normalize calcemia, expose the patient to hypercalciuria and impact quality-of-life. Human parathormone (PTH) replacement therapy is a suitable option in these cases, although few clinical reports have been published so far. Methods: We describe two cases of patients with refractory postsurgical hypoPTH, in whom subcutaneous infusion of recombinant PTH (teriparatide) through the Omnipod® pump was initiated after failure of all other therapeutic options. Besides, we performed a review of literature of hypoPTH cases treated by continuous infusion of teriparatide. Results: Two women aged 46 and 61 years old failed to normalize calcemia either with conventional treatments (calcium 8 g/day + calcitriol 9 mcg/day and calcium 5 g/day + calcitriol 12 mcg/day) or with thrice daily subcutaneous injections of teriparatide. As a last resort, teriparatide infusion via Omnipod® device normalized their calcemia and allowed calcium/vitamin D withdrawal, with average teriparatide dose of 23 and 32 mcg/day, respectively. The flow of teriparatide was adapted according to a protocol based on measured calcemia, under medical supervision. In the literature, 15 adult cases (13 women, mean age 44.5 ± 5.2 years old) are reported. HypoPTH was consecutive to surgery in all of them. Mean dose of teriparatide administered was 25 ± 6 mcg/day with improvement of calcemia level and quality-of-life in all patients. Conclusions: Continuous administration of teriparatide through Omnipod® appears as an efficient therapeutic option in refractory hypoPTH, whose administration to the patient can be assisted by medically-supervised protocol. [ABSTRACT FROM AUTHOR]

The article presents the influence of oil viscosity on the overall efficiency of the compared systems with proportional cylinder control. There are energy losses in the elements of the hydraulic system, which are, among other things, a function of the viscosity of the working fluid used, as well as energy losses which are practically independent of the viscosity. In order to assess the possibilities of saving energy during the operation of the hydrostatic drive system, it is necessary to understand and describe the losses occurring in the system. Determining the energy efficiency of the system can be performed simulation with the help of a computer program using an appropriate mathematical model. The efficiency determined in this way can be used in the process of designing and operating the system. [ABSTRACT FROM AUTHOR]

This study aims to explore the gas-liquid two-phase flows during the self-priming process in an external-mixing self-priming centrifugal pump using Euler-Euler modeling, with an emphasis on the transient flow characteristics and the underlying mechanisms for the oscillating of the gas-liquid interface in the suction pipe. A homogeneous multiphase model (without considering the interphase velocity slip), and the standard k-ε turbulence model were adopted in the simulation. The opening boundary conditions were applied for the fluid at the inlet and outlet of the calculation domain, in order to capture the rising process of liquid level in the suction pipe. The speed was measured to determine the rotating speed of the rotor. The speed acceleration was then performed on the self-priming during the start-up process of the pump. The transient flow fields of the main components were investigated to reveal the gross features of the gas-liquid interface rising in the suction pipe, the mass flow rate of the liquid at the impeller inlet, the average gas volume fractions of pump components, and gas-liquid distribution in the flow passage of the pump. The simulated rising process of the gas-liquid interface in the suction pipe was agreed well with the experimental measurements. It infers that the opening boundary conditions were suitable for the reverse flow in the suction pipe caused by pressure oscillation in the impeller. The transient liquid phase flow rate at the impeller inlet indicated that the self-priming process was divided into three stages, namely the rapid absorbing, the oscillating exhaust, and the accelerating exhaust stage. The duration of the three stages accounted for 11.7%, 61.3% and 27% of the total self-priming time, respectively. The impeller rotating speed increased sharply at the rapid absorbing stage, where the initially stored liquid in the suction chamber was quickly sucked into the impeller to discharge the gas in the impeller. The oscillating exhaust was the main stage of the self-priming process, where the liquid in the gas-liquid separation chamber repeatedly entered the volute and the vicinity of the impeller outlet through the reflux hole in the process of gas-liquid mixing and gas exhausting. There was a periodic change with 0.25 s in the volume fraction of gas in the main pump components and the oscillation of liquid level in the suction pipe. But the inertia of the liquid column caused a phase gap between the liquid level oscillation and the pressure fluctuation at the impeller entrance. The oscillation amplitude of the gas-liquid interface increased with the increase of liquid column height. The accelerating exhaust stage was the final stage of the self-priming process, where the liquid in the suction pipe rapidly entered the impeller and the gas in the pump was quickly discharged. The finding can also provide an important reference for the design and performance optimization of self-priming centrifugal pumps. [ABSTRACT FROM AUTHOR]

The article deals with the design of an educational training device for solving control systems for regulating the water level in the reservoir. The system allows several options for operation with different control algorithms. The device can be connected to the control system for practical training activities in the educational process. [ABSTRACT FROM AUTHOR]

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]

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]

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 key equipment of oil and gas pipelines is the important treasure of a country because they are related to national energy security. For many years, the key equipment has been imported, which become a bottleneck restricting the high-quality development of oil and gas industry in China. Thus, great attention was attracted from the CPC Central Committee and the State Council to localization, and it was decided to fully guard against and mitigate the risk of "stranglehold" through independent research. With the powerful support of the National Energy Administration and China Machinery Industry Federation, CNPC launched the localization work for equipment in oil and gas pipelines in 2007, set up two batches of major projects of science and technology localization, cooperated with 35 domestic manufacturers. As a result, a major breakthrough was made in the localization of 6 kinds of key equipment, such as compressor unit, oil pump set and valve, which breaks the foreign monopoly, ensures the independence and controllability of oil and gas energy, and further promotes the development of domestic equipment manufacturing to the high end.

Relevance. Gas condensate is a valuable raw material for oil refining and petrochemical production, therefore an increase in the degree of its extraction from gas of the gas condensate fields at field installations is an important scientific and technical problem. The aim of the study is to substantiate the possibility of increasing the yield of unstable condensate – C3 + fraction from the gas stream at operating complex gas and condensate treatment plant of one of the oil and gas condensate fields in the Far North by changing the operating parameters of the low-temperature absorption. The object: field plant of low-temperature absorption. Method: simulations of separation and low-temperature absorption in the software package «PetroSim». Results. The authors have studied the influence of pressure and temperature, gas flow, specific flow rate and composition of the absorbent – unstable condensate, on the efficiency of the gas and condensate preparation at complex gas and condensate treatment plant computer model of low-temperature absorption and low-temperature separation. It is shown that the low-temperature absorption application at the last stage of separation for the considered raw gas composition provides an output of the target C3+ fraction approximately two times greater in a wide range of pressures and temperatures compared to the low-temperature separation. The possibility of increasing the degree of the C3+ fraction extraction into commercial unstable condensate at the last stage of separation in the low-temperature absorption by 21 % is justified only by optimizing the operating parameters of the unit without changing the technological scheme. At the raw gas flow rate of 225 m3/hour the C3+ fraction extraction into unstable commercial condensate increases to 6,6 g/m3 of raw gas without modernization of the technological scheme of the unit, and this is an additional over 35 MT/day C3+ fraction with a corresponding reduction in its entrainment with the product gas, by optimization of low-temperature absorption thermobaric parameters (change of pressure from 3,75 to 5,0 MPa and temperature from minus 30 to minus 35 °C). When «weighting» the component composition of the absorbent by reducing the pressure in the unstable condensate separator of the first stage separation the degree of extraction of C3+ fraction in the product unstable condensate in the low-temperature absorber increases by 25 %, i. e. 6,6 g/m3, and this is 7 MT/day in addition with a corresponding further reduction of its content in the product gas. However, the implementation of such a regime already requires minimal modernization of the low-temperature absorption unit by inserting a pump into the process pipeline for supplying unstable irrigation condensate from the R-1 separator to a low-temperature absorber, which is repaid in a short time.

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]

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]