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Jet pumps are widely used in petrochemical processes, nuclear cooling, and wastewater treatment due to their simple structure, high reliability, and stable performance under extreme conditions. However, when transporting solid-laden two-phase flows, they face severe erosion problems, leading to reduced efficiency, malfunctions, or even failure. Therefore, optimizing jet pump performance and extending its service life is crucial. In this study, an experimental platform was established to conduct experiments on wall erosion in jet pumps. The CFD-DEM method was used to simulate the solid–liquid two-phase flow in the jet pump, comparing six erosion models for predicting erosion rates. The Grey Wolf Optimization algorithm was applied to calibrate model coefficients. The results indicate that the Neilson erosion model shows the best consistency with the experimental results. The inlet flow rate significantly influenced the erosion rates, while the flow rate ratio had a smaller effect. The particle concentration exhibited a nonlinear relationship with erosion, with diminishing impact beyond a certain threshold. As the factors varied, the erosion distribution tended to be uniform, but high erosion areas remained locally concentrated, indicating intensified localized erosion. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering 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.)

Abstract Existing ice particle jet surface treatment technology is prone to ice particle adhesion during application, significantly affecting surface treatment efficiency. Based on the basic structure of the jet pump, the ice particle air jet surface treatment technology is proposed for the instant preparation and utilization of ice particles, solving the problem of ice particle adhesion and clogging. To achieve efficient utilization of ice particles and high-speed jetting, an integrated jet structure for ice particle ejection and acceleration was developed. The influence of the working nozzle position (L d), expansion ratio (n), and acceleration nozzle diameter ratio (D n) length-to-diameter ratio (L n) on the ice particle ejection and acceleration was systematically studied. The structural parameters of the ejector were determined using the impact kinetic energy of ice particles as the comprehensive evaluation index, and the surface treatment test was conducted to verify the results. The study shows that under 2 MPa air pressure, the ejector nozzle parameters of n = 1.5, D n = 4.0, L d = 4, and L n = 0 mm can effectively eject and accelerate the ice particles. The aluminum alloy plate depainting test obtained a larger paint removal radius and resulted in a smoother aluminum alloy plate surface, reducing the surface roughness from 3.194 ± 0.489 μm to 1.156 ± 0.136 μm. The immediate preparation and utilization of ice particles solved the problems of adhesion and storage in the engineering application of ice particle air jet technology, providing a feasible technical method in the field of material surface treatment.

Natural gas hydrate (NGH) trials have been performed successfully with different development methods and gas recovery drainage technologies. Multiphase flow in a wellbore and the drainage of natural gas hydrate are two important parts for its whole extraction process. Additionally, the choice of the drainage method is linked to the development method, making the drainage of NGH more complex. Jet pump drainage is usable for NGH production wells with the combined depressurization and thermal stimulation method. The objective of this study is to shed more light on the multiphase flow behavior in jet pump drainage and NGH production wells and put forward suggestions for adjusting heat injection parameters. The mechanism of jet pump drainage recovery technology for NGH wells was analyzed and its applicability to NGH development by the combined depressurization and thermal stimulation method was demonstrated. In addition, multiphase flow models of tubing and annulus were established, respectively, for the phenomenon of the countercurrent flow of heat exchange in the process of jet pump drainage and gas production, and the corresponding multiphase flow laws were derived. On the basis of these studies, sensitivity analysis and the optimization of thermal stimulation parameters were conducted. It is demonstrated that jet pump drainage gas recovery technology is feasible for the development of onshore NGH with the combined depressurization and thermal stimulation method. The laws of multiphase flow in the tubing and annulus of jet pump drainage and NGH production wells were disclosed in this study. Numerical simulation results show that the temperature and pressure profiles along the wellbore of jet pump drainage and NGH production wells during the drainage recovery process are affected by injection conditions. Increasing injection rate and injection temperature can both improve the effect of heat injection and reduce the hydrate reformation risk in the bottom of the annulus. This study offers a theoretical basis and technical support for production optimization and hydrate prevention and control in the wellbore of jet pump drainage and NGH production wells. [ABSTRACT FROM AUTHOR]

Silt removal is crucial for maintaining navigable waterways in harbors. Jet pumps, without moving parts, are highly suitable for underwater operations such as channel dredging in port environments. Despite their structural advantages in slurry handling, the prolonged transport of solid–liquid two-phase flows can lead to wear on the wall materials, resulting in decreased efficiency and potential pump failure. The wear characteristics of the jet pump walls due to sand particles of varying grain sizes were experimentally investigated. The characteristic of the sands having a higher distribution above the axis as they enter the jet pump was captured by a high-speed camera. The experiment recorded the variations in mass loss at different sections of the jet pump over a period of 120 h, identifying that backflow within the throat region is a significant contributor to wall wear. Scanning electron microscopy was employed to examine the microstructure of the abraded pump surfaces. It was found that there are noticeable differences in the surface wear microstructure across various pump areas, and that particles of different grain sizes result in distinct wear patterns on the pump surfaces. The underlying causes of this phenomenon were discussed from the perspective of particle motion. [ABSTRACT FROM AUTHOR]

This paper presents a preliminary study of a novel type of turbulizers based on the jet pump working principle and designed to intensify heat transfer in double-tube heat exchangers. To determine the potential for their use, Computational Fluid Dynamics (CFD) and realizable k-ε turbulence model were applied to four turbulizers differing in the angles and diameters of the nozzle and diffuser. During studies, a number of parameters were determined, including: (i) Euler number Eu, (ii) overall heat transfer coefficient kT and (iii) reduced ratio of heat duty to mechanical power 𝜀r; and then compared with data available for strip turbulizers. The tests yielded the following maximum values of: Eu - 1.5 times higher, kT - 2 times higher, and 𝜀𝑟 - 27 times higher than those obtained by classical strip turbulizers, which indicates the high potential of presented jet pump turbulizers and justifies their further development. [ABSTRACT FROM AUTHOR]

Jet pumps are widely used in petrochemical processes, nuclear cooling, and wastewater treatment due to their simple structure, high reliability, and stable performance under extreme conditions. However, when transporting solid-laden two-phase flows, they face severe erosion problems, leading to reduced efficiency, malfunctions, or even failure. Therefore, optimizing jet pump performance and extending its service life is crucial. In this study, an experimental platform was established to conduct experiments on wall erosion in jet pumps. The CFD-DEM method was used to simulate the solid–liquid two-phase flow in the jet pump, comparing six erosion models for predicting erosion rates. The Grey Wolf Optimization algorithm was applied to calibrate model coefficients. The results indicate that the Neilson erosion model shows the best consistency with the experimental results. The inlet flow rate significantly influenced the erosion rates, while the flow rate ratio had a smaller effect. The particle concentration exhibited a nonlinear relationship with erosion, with diminishing impact beyond a certain threshold. As the factors varied, the erosion distribution tended to be uniform, but high erosion areas remained locally concentrated, indicating intensified localized erosion.

Relevance. Today oil production by installations of electric centrifugal pumps is one of the leading methods of mechanized oil production. The mechanized operation of hard-to-recover oil objects is complicated by the high viscosity of reservoir oil, the formation of wax-deposits in the wellbore. This leads to an increase in hydraulic resistances due to a decrease in the flow section of pipes and other pumping equipment components, a decrease in the productivity of wells and the efficiency of pumping production. In this regard, an urgent task is to develop and improve methods and devices for preventing deposits of wax-deposits in wells. Object. Downhole pumping unit for dosing reagent (inhibitor of wax-deposits) into the well, which is a combination of two technical devices – a pump dosing the reagent and a jet pump. Aim. To analyze the influence of the design parameters of the dosing unit on the efficiency of its operation (reagent consumption, liquid cavitation coefficient in the jet pump). Methods. Mathematical modeling of the operation of a downhole dosing unit for the supply of reagent, based on the application of the laws of conservation of mass and quantity of motion, as well as Bernoulli's law for a moving flow in a jet pump. Results. Based on the simulation results, the nature of the influence of the design parameters of the developed installation on the reagent consumption is established. It is established that the maximum flow rate of the reagent is achieved with a mixing chamber diameter of about 22 mm; an increase in diameter relative to the specified value leads to a decrease in the degree of local pressure reduction, a decrease in the diameter of the mixing chamber – a drop in flow due to an increase in the flow rate in the chamber and an increase in hydraulic resistance. It was found that an increase in the supply of electric centrifugal pumps in the considered range of 100–200 m3 per day has practically no effect on the reagent consumption when the mixing chamber diameter is more than 30 mm. It was found that at confuser length values exceeding 210 mm, the cavitation coefficient, regardless of the mixing chamber diameter, exceeds one, which indicates a smooth and uniform pressure reduction in the device body. In general, it is shown that by regulating the design parameters of a downhole metering unit, it is possible to ensure the required reagent consumption at a known electric centrifugal pump supply (well flow rate).

Silt removal is crucial for maintaining navigable waterways in harbors. Jet pumps, without moving parts, are highly suitable for underwater operations such as channel dredging in port environments. Despite their structural advantages in slurry handling, the prolonged transport of solid–liquid two-phase flows can lead to wear on the wall materials, resulting in decreased efficiency and potential pump failure. The wear characteristics of the jet pump walls due to sand particles of varying grain sizes were experimentally investigated. The characteristic of the sands having a higher distribution above the axis as they enter the jet pump was captured by a high-speed camera. The experiment recorded the variations in mass loss at different sections of the jet pump over a period of 120 h, identifying that backflow within the throat region is a significant contributor to wall wear. Scanning electron microscopy was employed to examine the microstructure of the abraded pump surfaces. It was found that there are noticeable differences in the surface wear microstructure across various pump areas, and that particles of different grain sizes result in distinct wear patterns on the pump surfaces. The underlying causes of this phenomenon were discussed from the perspective of particle motion.

Natural gas hydrate (NGH) trials have been performed successfully with different development methods and gas recovery drainage technologies. Multiphase flow in a wellbore and the drainage of natural gas hydrate are two important parts for its whole extraction process. Additionally, the choice of the drainage method is linked to the development method, making the drainage of NGH more complex. Jet pump drainage is usable for NGH production wells with the combined depressurization and thermal stimulation method. The objective of this study is to shed more light on the multiphase flow behavior in jet pump drainage and NGH production wells and put forward suggestions for adjusting heat injection parameters. The mechanism of jet pump drainage recovery technology for NGH wells was analyzed and its applicability to NGH development by the combined depressurization and thermal stimulation method was demonstrated. In addition, multiphase flow models of tubing and annulus were established, respectively, for the phenomenon of the countercurrent flow of heat exchange in the process of jet pump drainage and gas production, and the corresponding multiphase flow laws were derived. On the basis of these studies, sensitivity analysis and the optimization of thermal stimulation parameters were conducted. It is demonstrated that jet pump drainage gas recovery technology is feasible for the development of onshore NGH with the combined depressurization and thermal stimulation method. The laws of multiphase flow in the tubing and annulus of jet pump drainage and NGH production wells were disclosed in this study. Numerical simulation results show that the temperature and pressure profiles along the wellbore of jet pump drainage and NGH production wells during the drainage recovery process are affected by injection conditions. Increasing injection rate and injection temperature can both improve the effect of heat injection and reduce the hydrate reformation risk in the bottom of the annulus. This study offers a theoretical basis and technical support for production optimization and hydrate prevention and control in the wellbore of jet pump drainage and NGH production wells.

A system for pumping wastewater and solid sediments from the territories and buildings of the pumping and hydroelectric stations using jet pumps is proposed. The working and suction media have different aggregate state, including water and pulp, containing solid sediments from the station canals. The rate of sediment removal from the flow provided by the jet pump is determined depending on the water turbidity in the supply canal of the pumping station. [ABSTRACT FROM AUTHOR]

Experimental research was conducted on the performance curves and the cavity evolution for different flow and geometric parameters in jet pumps for zero flow ratio (ZFR) conditions. New pressure ratio, Pr, flow ratio, qr, were used in place of the conventional performance parameters h, q, to characterize the jet pump flow performance. A super cavitation cavity in the jet pump was observed to fill most of the flow channel, which hindered further increases of the flow rate and increased qr to one, thus, created a critical point on the new Pr - qr2 curve. Before the critical point, Pr was proportional to qr2 with a coefficient that was much more sensitive to the area ratio than the relative throat length and the diffusion angle. After the critical point, the flow rate reached its maximum, the limiting flow rate, which only depended on the total inlet pressure and the area ratio. The total inlet pressure was proportional to the square of the limiting flow rate with a flow coefficient that was only a quadratic function of the area ratio. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute 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.)

A new integrated oil production enhancement technology based on water-flooding energy recovery is proposed. After providing an extensive review of the existing scientific and technical literature on this subject, the proposed integrated technology is described together with the related process flow diagram, the criteria used to select a target facility for its implementation and the outcomes of the laboratory studies conducted to analyze emulsion formation and separation kinetics. Moreover, the outcomes of numerical simulations performed using Ansys CFX software are also presented. According to these results, using the proposed approach the incremental oil production may reach 1.2 t/day (with a 13% increase) and more, even at low flow rates (less than 10 t/day), thereby providing evidence for the benefits associated with this integrated technology. [ABSTRACT FROM AUTHOR]

【Objective】 Jet pump has a wide applications in many areas and water flow in it is affected by many design parameters. In this paper, we analyzed numerically the influence of the outlet position and diameter of the suction pipe on efficiency and flow field of annular jet pump. 【Method】 The numerical model was based on the turbulence model, and water flow in pumps with different configurations was simulated using the software FLUENT under different flow ratios. 【Result】 The outlet position of the suction pipe should not be far away from the inlet of the contraction section of the suction chamber when the flow ratio was 0.4~0.6; for what we studied, 2mm was the optimal distance. When the flow ratio was in the range of 0.1~0.3, increasing the spacing between the outlet and the inlet of the contraction section of the suction chamber could improve the efficiency of the pump. The efficiency of the pump is positively correlated with the suction tube diameter when other parameters are the same. 【Conclusion】 The change in flow ratio results in a change in the optimal outlet position of the suction pipe. The maximum efficiency of the annular jet pump and the flow ratio corresponding to the maximum efficiency point both increased, as the diameter of the suction pipe increased.

This article analyzes the possibility of increasing the efficiency of using downhole jet pumps by swirling the injected flow. To analyze the peculiarities of the local swirling of injected flow, design and technological parameters in the form of the inclination angle of guiding elements, the diameter of the helical trajectory described by the fluid particles, and the flow rates of the swirling flow are studied. Based on the application of the conservation law of fluid momentum in adjacent jets with a parabolic pressure distribution, equations to determine the pressure characteristic of a jet pump are obtained, taking into account the additional dynamic pressure made by swirling the injected flow. In the process of analyzing the obtained relations, has been set the dependence of the relative pressure growth and the efficiency of the ejection system under the conditions of injected flow swirling on the relative flow rate of a jet pump, and an inversely proportional dependence of the above parameters on its main geometric parameter in the form of the ratio of cross-sectional areas of the mixing chamber and the nozzle.

• The synchronous measurement is used to study the chocked cavitation flow. • The evolution of chocked cavitation flow can be divided into three regions. • Cavitation average length has a two-stage linear relation with outlet pressure ratio. • Changes in cavitation areas correlate with pressure fluctuations. • The high reverse pressure gradient at the tail causes cavitation cloud oscillation. Experiments were conducted in this study to investigate the chocked cavitation characteristics and its oscillation mechanism in jet pump cavitation reactors (JPCR) under limited operation stage (LOS) utilizing a synchronous measurement system. The pulsation characteristics of cavitation in JPCR under various inlet and outlet pressures were analyzed by the processed high-speed camera images. Furthermore, correlation between cavitation and pressure pulsation as well as the mechanism of cavitation oscillation in JPCR under LOS are elucidated based on synchronized measurements. The results reveal that the typical jet choked cavitation flow field can be divided into three characteristic regions, i.e., stability region, oscillation region and collapse region. Changes in flow parameters cause variations in the areas of these three regions and shift the initial and collapse positions of cavitation. The time-averaged length of cavitation clouds varies linearly with the absolute pressure ratio at the outlet, corresponding to both stable and unstable LOS. Notably, the results reveal a clear correlation between the grayscale of cavitation clouds and pressure fluctuations over time, identifying the inverse pressure gradient as the primary cause of cavitation oscillation in the throat tube during unstable LOS. [ABSTRACT FROM AUTHOR]

In order to fulfill the present need for downhole lifting pumps in various cutting-edge drilling techniques, a double jet pump is ingeniously devised. The internal three-dimensional characteristics of this pump are utilized to optimize its structural parameters through the flow field simulation method. Extensive evaluations are conducted to assess the alterations in jet performance under different parameters, including area ratios, throat lengths, nozzle exit positions, and nozzle area ratios. The pivotal structural parameters of the double jet pump are optimized as follows: area ratio m a = 0.22 , throat length L h = 84.5 mm, nozzle exit position L c = 6.76 mm, and nozzle area ratio m b = 0.3. Furthermore, an experimental platform is meticulously erected to validate the principles of the double jet pump and to analyze its jet performance. This ascertains the feasibility of the double jet pump and validates the accuracy of the simulation and analysis results. This device can be effectively employed in the oil and gas production characterized by a high sand content extraction. • A double jet pump with a diverting function is proposed. • This device can enhance extraction processes encountering high sand content. • Determine the influence of various parameters on its working characteristics. • Conduct relevant experiments to verify the feasibility of the double jet pump and the accuracy of its performance. [ABSTRACT FROM AUTHOR]

Through the experimental verification, the accuracy of the cavitation jet feature captured by the coupling numerical calculation with different mesh types and different turbulence models is evaluated. Firstly, we built a high-speed jet experimental platform, and a high-speed camera and a paperless recorder are used to record the pressure, flow rate, and jet cloud oscillation of the jet pump in different states. The oscillation period and length of the jet cloud under different cavitation numbers are analyzed by the gray value method. The numerical results are compared with the experimental results. It is found that after the numerical calculation converges, the states of the jet cloud calculated by K–O and LES coupled with different meshes are periodically oscillating, while K-E does not. However, the maximum jet cloud lengths calculated by K-E and K–O turbulence models under different mesh types are nearly the same. Overall, the oscillation period calculated by the LES model is more in line with the experimental results, but its amplitude and maximum length are more different from the experimental results. In terms of capturing the jet cloud, critical pressure ratio, turbulent state and vapor volume fraction, the accuracy order of numerical calculation results are P–H (polyhedron-hexahedron mesh) ≈ P (polyhedron mesh) > H-T (hexahedral-tetrahedral mesh) > T (tetrahedral mesh), P–H ≈ P > T > H-T, P–H ≈ P > H-T > T and P–H > P > T > H-T, respectively. This research can provide more appropriate solutions for different concerns, as well as guidance for improving the accuracy and efficiency of simulations, and provides a basis for optimizing and developing specialized mesh types and turbulence models. • Based on K–O, the order of accuracy for capturing the jet cloud is P–H ≈ P > H-T > T. • Based on K-E, the order of accuracy for capturing h c r and P s is P–H ≈ P > T > H-T. • The I and ε obtained by the numerical calculation of P–H are the most accurate. • P–H captures the vapor volume fraction more accurately, H-T is the worst. [ABSTRACT FROM AUTHOR]

Features typical for using a jet pump to lift fluid from a tank placed in a deep-level mine are considered. The paper proposes a technique to estimate the output of a jet pump taking into account the geometric, hydraulic parameters and scheme peculiarities of the system. The dependence of the system parameters upon the pump output is studied. Recommendations for using the technique in design and operation calculations of the jet pump output in the same systems are resulted from the study. [ABSTRACT FROM AUTHOR]

Ignition within gas burner ejectors can lead to off design conditions and has significant influence on the burner behavior. Thus ignition in the ejector should be prevented. In the present study the influence of combustion reactions on the performance of gas burner injectors is investigated. To investigate if ignition is possible, simulated ignition delay times, using a detailed reaction mechanism, are compared to predicted mean residence times of the gas in the ejector. Gas burner ejectors are designed using one dimensional analytic equations, based on energy and momentum conservation equations and conventional isentropic equations. 1D results are compared to 2D computational fluid dynamics (CFD) simulations, to take into account non-ideal mixing effects along the ejector. Results are validated with experiments with air at room temperature. 1D results show very good agreement not only with CFD simulations for the case of non-reactive flows, but also with performed experiments.It is shown that the assumption of ideal mixing along the ejector and thus the comparison of the ignition delay time to the gas mean residence time, to predict ignition in the ejector, is not valid. Ignition in the ejector is possible, even if the ignition delay time is more than thirty times higher than the mean residence time. In addition to that, it is shown, that ignition and the choice of reaction mechanism have significant influence on the predicted gas burner ejector performance. Thus, the accurate prediction of ignition delay time and the use of a detailed reaction kinetic are mandatory to correctly predict the burner ejector behavior.

An analytical dependence of the pressure at the inlet to the jet pump suction chamber on the working flow rate was obtained based on the pressure values determined in the characteristic sections of the borehole ejection system in accordance with the flow modes of the working fluid in its elements. The proposed equation includes the borehole hydrostatic pressure, the pressure loss both in the annulus and the working nozzle of the jet pump, as well as the relative head created by the ejection system. According to the results of simulating the jet pump working process, the borehole pressure was established to be inversely proportional to the working flow rate and directly proportional to the ratio of the jet pump mixing chamber and the working nozzle areas. The jet pump allows for a twofold decrease in the borehole pressure as compared to the hydrostatic pressure. The duration of the hydrate elimination process and the required movement speed of the ejection system in the borehole are determined by the depth and intensity of deposit formation, temperature, jet pump design, and the working flow rate. The obtained performance characteristics confirm the possibility of using jet pumps to eliminate hydrates on the surfaces of the borehole underground equipment. [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.)

Abstract An annular powder‐liquid mixer is a new type of jet pump used to mix powder. This mixer is mainly used to mix fracturing fluids in oil and natural gas exploitation processes. Free from powder pellets, the mixer has characteristics, such as high mixing efficiency and great suction. The structural parameters, such as hose diameter, exit section diameter, falloff angle, divergence angle, hose length‐diameter ratio, and annular nozzle diameter, may influence this new type of mixer. By using an orthogonal experiment to optimize the structure of an annular ring‐type powder mixer and performing a comparative analysis of the results of numerical simulations, this paper finally determines the mixer's structure. According to experiments, the mixer's negative suction can reach 0.09 MPa, there are no powder pellets during the mixing process, and the mixing effect is very good.

In this paper, designing, manufacturing, and investigating water desalination using the energy dissipated in the refrigeration cycle is conducted in an experimental study. This study attempts to absorb the heat lost in the cooling cycle and to enter the desalination cycle, and to provide the evaporation needed for the water desalination in another cycle. The vacuum required during the desalination process is provided by a jet pump. The results indicated that changing the refrigeration cycle's condenser and receiving its dissipated energy in addition to providing the energy required for the desalination operation has not had any adverse effect on the cooling performance of the refrigeration cycle. Effect of the pressure chamber, compressor temperature, and cooling water on yield are presented. The amount of total dissolved solids obtained in this method was achieved up to 4 ppm. The results also showed that the energy-saving value in this study has been between 9.6 and 14.8 KJ. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Friction & Wear is the property of National Aviation University 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.)

Based on the construction project of 3 000 m3 trailing suction hopper dredger of the CCCC Shanghai Dredging Co., Ltd., combined with the development of the draghead of 4 500 m3 trailing suction hopper dredger in the project, the influence of the resistance along the drag arm jet water pipe system and the nozzle arrangement on the draghead jetting were studied. The flow velocity of the high -pressure jet pipeline and nozzle of the draghead of 4 500 m3 trailing suction hopper dredger was calculated by numerical simulation method, and the matching analysis of working points was carried out according to the performance curve of the high-pressure jet water pump. According to the flow field distribution of local flow surface near the nozzle, further optimize the shape of high-pressure flushing flow area and nozzle structure in the draghead, effectively reduce the pipeline resistance, reduce the energy loss in the process of high-pressure jet water transported to the nozzle along the drag arm pipeline, and significantly improve the nozzle jet water flow rate, and form the design scheme of draghead jet water pipe system and nozzle matching with the working point of high-pressure jet pump. [ABSTRACT FROM AUTHOR]

The paper presents the numerical and experimental studies carried out to optimize, from an aerodynamic point of view, a subsonic jet pump used on aircraft. The optimization of the subsonic jet pump will be done from the aerodynamic, aiming to re-design it such as to reduce as much as possible the emitted noise levels. For this, in a first stage, a parametric set of Reynolds Averaged Navier - Stokes numerical simulation was used on several possible designs, starting from an existing baseline, and including it. The goal was to identify the trends in the flow behavior when key baseline design parameters were varied. During the second stage, aerodynamic measurements were carried out on the two selected configurations and on the baseline configuration for the determination of the instantaneous flow velocity field. The measurements were carried out using cutting edge experimental measure techniques, namely Particle Image Velocimetry. The paper presents a comparison of the numerical and the experimental results and the conclusions of the analysis of the results.

The energy indexes of vortex ejector and jet pump performance are compared. The mixed media in the studied ejection process are liquids. The calculation schemes of the devices are given. The operation principle and design differences of the vortex ejector and the jet pump are described. The algorithms for calculations of the geometric parameters of vortex ejectors and jet pumps are given. Conclusions are drawn about the overall dimensions of the compared devices for different ejection factors and power consumptions. [ABSTRACT FROM AUTHOR]

The acoustic streaming is a key drawback and eliminates the performance of a jet pump-based thermoacoustic-Stirling heat engine. The present study deals with a new hybrid optimization approach to reduce the acoustic streaming energy. The proposed work is an integration of Taguchi method (TM), adaptive neural fuzzy inference system (ANFIS), and teaching–learning-based optimization (TLBO). The Taguchi method plays three important roles. The first role is to layout the number of experiments. The second role is to identify the most appropriate parameters for ANFIS structure regarding the number of input membership functions (MFs), types of input MFs, optimal learning method, and types of output MFs. In order to determine the optimum parameters for the ANFIS structure, the root-mean-squared error, a performance criterion, is minimized by using the TM. The final role of TM is to optimize the controllable parameters of the TLBO. Subsequently, modeling between geometric parameters and acoustic streaming is established by the built ANFIS structure. Finally, the TLBO is adopted by optimizing the design parameters. The outcomes of study revealed that the acoustic streaming is relatively reduced. Based on Wilcoxon signed-rank test and Friedman test, it proves that the effectiveness of the proposed hybrid approach is better to other evolutionary algorithms. The current approach is an efficient optimizer for complex optimization problems. [ABSTRACT FROM AUTHOR]

An annular powder‐liquid mixer is a new type of jet pump used to mix powder. This mixer is mainly used to mix fracturing fluids in oil and natural gas exploitation processes. Free from powder pellets, the mixer has characteristics, such as high mixing efficiency and great suction. The structural parameters, such as hose diameter, exit section diameter, falloff angle, divergence angle, hose length‐diameter ratio, and annular nozzle diameter, may influence this new type of mixer. By using an orthogonal experiment to optimize the structure of an annular ring‐type powder mixer and performing a comparative analysis of the results of numerical simulations, this paper finally determines the mixer's structure. According to experiments, the mixer's negative suction can reach 0.09 MPa, there are no powder pellets during the mixing process, and the mixing effect is very good. [ABSTRACT FROM AUTHOR]

This paper studies the unsteady three-dimensional cavitating turbulent flow in a jet pump. Specifically, thefocus is on the unstable limited operation stage, and both the computational and experimental methods are used. In the experiments, the distribution of the wall pressure, as well as the evolution of cavitation over time, are obtained for a jet pump. Computation is carried out using the large eddy simulation, combined with a mass transfer cavitation model. The numerical results are compared with the experimental results, including the fundamental performances (the pressure ratio h and the efficiency η), as well as the wall pressure distribution. Both the experimental and computational results indicate that the evolution of the cavitation over time in a jet pump is a quasi-periodic process during the unstable limited operation stage. The annular vortex cavitation inception, development and collapse predicted by the large eddy simulation agree fairly well with the experimental observations. Furthermore, the relationship between the cavitation and the vortex structure is discussed based on the numerical results, and it is shown that the development of the vortex structures in the jet pump is closely related to the evolution of the cavitation. The cavitation-vortex interaction is thoroughly analyzed based on the vorticity transport equation. This analysis reveals that the cavitation in a jet pump dramatically influences the distribution and the production of the vorticity. The process of the annular cavitation inception, development, and collapse involves a significant increase of the vorticity. [ABSTRACT FROM AUTHOR]

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In the Oil and Gas industry, installing pipe loops is a well-known hydraulic practice to increase oil pipeline capacities. Nevertheless, pipe loops could promote an unfavorable phenomenon known as fouling. That means that in a heavy oil-water mixture gathering system with low flow velocities, an oil-water stratified flow pattern will appear. In consequence, due to high viscosity, the oil stick on the pipe, causing a reduction of the effective diameter, reducing handled fluids production, and increasing energy consumption. As jet pumps increase total handled flow, increase the fluid velocities, and promote the homogenous mixture of oil and water, this type of pump could result attractive compared to other multiphase pump systems in reactivating heavy crude oil transport lines. Jet pumps are highly reliable, robust equipment with modest maintenance, ideal for many applications, mainly in the oil and gas industry. Nevertheless, their design method and performance analysis are rarely known in the literature and keep a high experimental component similar to most pumping equipment. This paper proposes a numerical study and the optimization of a booster multiphase jet pump system installed in a heavy oil conventional loop of a gathering system. First, the optimization of a traditionally designed jet pump, combining CFD simulation and optimization algorithms using commercials software (ANSYS CFX® and PIPEIT® tool), has been carried out. This method allowed evaluating the effect of multiple geometrical and operational variables that influence the global performance of the pump to run more than 400 geometries automatically in a reduced time frame. The optimized pump offers a substantial improvement over the original concerning total flow capacity (+17%), energy, and flow distribution. Then, the effect of the three jet pump plugin configurations in a heavy oil conventional trunkline loop was analyzed. Simulations were carried out for different driving fluid pressures and compared against a traditional pipeline loop’s performance. Optimum plugin connection increases fluid production by 30%. Finally, a new eccentric jet pump geometry has been proposed to improve exit velocities and pressure fields. This eccentric jet pump with the best connection was analyzed over the same conditions as the concentric optimized one. An improvement of 2% on handled fluid was achieved consistently with the observed uniform velocity field at the exit of the pump. A better total fluid distribution between the main and the loop line is obtained, handling around half of the complete fluid each.

A sediment bypassing plant based on innovative jet pump, ejectors, has been tested in the first-of-a-kind demo application at the harbor of Cervia (Italy, Northern Adriatic Sea). The ejector is a jet pump aimed to reduce sediment accumulation in navigation channels and coastal areas. Herein we present results of the first study assessing the potential ecological effects of the ejectors plant. Sediment characteristics, benthic, and fish assemblages before and after the plant activation have been analyzed in the putatively impacted (the sediment removal and discharge) areas and four control locations, one time before and two times after plant activation. Ejectors plant operation resulted in a reduction of the mud and organic matter content in the sediment, as well as in changes in shell debris amount in the impacted areas. Abundance and species richness of benthic macroinvertebrates, initially reduced in the impacted areas, probably due to the previous repeated dredging, returned to higher values during demo plant continuous operation. Higher diversity of fish fauna was observed in the study area during plant operation period. Observed dynamics of the ecological status of the marine habitat suggest that an ejectors plant could represent an eco-friendly solution alternative to dredging operations to solve harbor siltation problems.

During oil fields operation, gas is extracted along with oil. In this article it is suggested to use jet pumps for utilization of the associated oil gas, burning of which causes environmental degradation and poses a potential threat to the human body. In order to determine the possibility of simultaneous application of a sucker-rod pump, which is driven by a rocking machine, and a jet pump (ejector) in the oil well, it is necessary to estimate the distribution of pressure along the borehole from the bottomhole to the mouth for two cases: when the well is operated only be the sucker-rod pump and while additional installation of the oil-gas jet pump above its dynamic level. For this purpose, commonly known methods of Poettman-Carpenter and Baksendel were used. In addition, the equations of high-pressure and low-pressure oil-gas jet pumps were obtained for the case, when the working stream of the jet pump is a gas-oil production mixture and the injected stream is a gas from the annulus of the well. The values which are included in the resulting equations are interrelated and can only be found in a certain sequence. Therefore, a special methodology has been developed for the practical usage of these equations in order to calculate the working parameters of a jet pump based on the given independent working parameters of the oil well. Using this methodology, which was implemented in computer programs, many operating parameters were calculated both for the well and for the jet pump itself (pressures, densities of working, injected and mixed flows, flow velocities and other parameters in control sections). According to the results of calculations, graphs were built that indicate a number of regularities during the oil well operation with such a jet pump. The main result of the performed research is a recommendation list on the choice of the oil-gas jet pump location inside the selected oil well and generalization of the principles for choosing the perfect location of such ejectors for other wells. The novelty of the proposed study lays in a systematic approach to rod pump and our patented ejector pump operation in the oil and chrome plating of pump parts. The result of scientific research is a sound method of determining the rational location of the ejector in the oil well and the calculation of its geometry, which will provide a complete selection of petroleum gas released into the annulus of the oil well. To ensure reliable operation of jet and plunger pumps in oil wells, it is proposed to use reinforcement of parts (bushings, plungers, rods, etc.) by electrochemical chromium plating in a flowing electrolyte. This has significantly increased the wear resistance and corrosion resistance of the operational surfaces of these parts and, accordingly, the service life of the pumps. Such measures will contribute to oil production intensification from wells and improve the environmental condition of oil fields.

The effect of operational and geometrical parameters on the jet pump efficiency were determined experimentally and numerically. Numerical investigation was held firstly to determine the effect of diffuser angle, mixing chamber length, pump area ratio and driving nozzle position on the efficiency of jet pump. Commercial computational fluid dynamics (CFD) solver ANSYS FLUENT R 15.0 using SST-turbulence model was used. The numerical results showed that jet pump efficiency increases with decreasing both of diffuser angles and mixing chamber length up to a certain value and then pump efficiency decreases. Also, jet pump efficiency increases with increasing pump area ratio up to a certain value and then pump efficiency decreases. It was found that maximum numerical efficiency is 37.8 % for pump area ratio of 0.271. In addition, the numerical results showed that the optimum relative length of mixing chamber is 5.48 and the optimum value for diffuser angle at which the efficiency is a maximum value is 5º. Experimental tests were conducted to obtain the effects of various operational and geometrical parameters on the performance of the jet pumps. A test rig was constructed using the optimum design from the numerical results. The CFD’s results were found to agree well with actual values obtained from the experimental results.

Synthetic jets, whose size and weight can be reduced easily, have become an attractive alternative to continuous jets. Many experimental and numerical studies have been conducted on synthetic jets to investigate their fundamental flow characteristics, including jet structure, for applied research such as boundary layer control and enhanced fluid mixing. However, few studies have focused on fluid transportation devices using synthetic jets as a driving source. Therefore, several issues concerning fluid transport characteristics still need to be resolved. In addition, although optimum operation of devices using synthetic jets is essential for their practical use, few studies have focused on this issue. The present study experimentally demonstrates the influence of the dimensionless stoke L on the performance characteristics of a synthetic jet fan under Reynolds number Re = 1800 and the same fan geometry; here, the stroke l is nondimensionalized by the primary slot width b. Furthermore, numerical simulations are conducted to complement the experiment. Velocity and pressure measurements are performed using a hot-wire anemometer, differential pressure manometer, and pressure transducer. The influence of the dimensionless stroke L on the performance/efficiency curves, static pressure distribution on the duct surface, and unsteady flow characteristics are investigated. Moreover, the flow field inside the duct is observed through numerical simulation. The results show that the performance characteristics and pressure recovery process depend on the dimensionless stroke L, and an optimum range of dimensionless stroke L exists for operation.

What is important in artificial lift installations to the mature oil filed is flexible operations and the appropriate installation schedule considering uncertainty of production forecasts. The reason is that it is expected to minimize the installation and operation costs, in addition to accelerate oil recovery. This paper introduces challenges and approaches for optimization of jet pump installations for the Ayukawa field in Japan. [ABSTRACT FROM AUTHOR]

Approaches to enhance oil and gas recovery by artificial lift, EOR/IOR and well stimulation for existing wells have been required due to maturation of domestic oil and gas fields and decline in oil prices. However, these new approaches have not always been considered on well designs based on earlier drilling, completion and production operations and other challenges might arise later in order to maintain well integrity. This paper reviews challenges focusing on well integrity issues on existing wells and gaps between conventional well designs and load conditions of the new approaches and introduce an example of applying Jet Pump on an existing well with resolving issues. [ABSTRACT FROM AUTHOR]

Abstract The characteristics of two-phase flow through a 'conventional' convergent-nozzle in an entrainment chamber of an ejector apparatus are described in this paper. A unique data set comprising 350 data points was generated in an air-water horizontal test-rig. Two sets of flow conditions were established, the first one including high liquid - low gas fluids with void fractions less than 0.55, and the second one involving high gas - low liquid fluids with void fractions greater than 0.75. All considered flow-rates lied within the sub-critical flow region. Two-phase flow pressure drop multiplier based empirical correlations were developed to estimate the total mass flow-rates. In the high liquid region, Morris (1985) correlation was modified, resulting in less than 10% error. In the high gas region, two new correlations were proposed, showing less than 10% and 15% of errors, respectively. The established empirical correlations were related to other available multipliers for different geometric configurations including a Venturi, an orifice plate, a gate valve, and a globe valve and were compared to 20 other void fraction correlations. The Chisholm (1983b) and Huq and Loth (1992) correlations showed the highest similarities to the ones proposed for the high liquid and high gas regions, respectively. [ABSTRACT FROM AUTHOR]