Jet Pressure Research Articles

Influence of SiC pellets water jet peening on the surface integrity of 7075-T6 aluminum alloy

This work investigates the influences of water jet parameters, including jet pressure, nozzle moving speed, target range, and track interval, on the shot peening of 7075-T6 aluminum alloy. SiC pellets 0.1 mm in diameter are added into the water jet peening (WJP) process. The shot peened workpiece surface is then measured with a roughness tester, a microhardness METER, a METALLURGRAPHIC microscope (MO), and a scanning electron microscope (SEM). The influences of solid pellet WJP on workpiece surface roughness, microhardness, surface residual stress, and surface topography are examined. The results show that jet pressure is positively proportional to surface roughness and microhardness. However as nozzle moving speed and target range increase, the surface roughness and microhardness of the shot peened workpiece begin to decrease. At the track interval of 0.15 mm, the surface roughness of the treated workpiece is a minimum of 0.61 μm. The surface residual stress of the treated workpiece is also notably improved. The residual stress perpendicular to the trajectory is marginally higher than that along the trajectory, but the difference is limited. Further studies reveal that solid pellet WJF treatment of 7075-T6 is the most effective in the jet pressure interval of 25 MPã30 MPa. The optimal nozzle moving speed is 650 mm/miñ750 mm/min. The target range can be selected between 10 and 12.5 mm. The track interval must be greater than 0.1 mm.

Insights of abrasive water jet polishing process characteristics and its advancements

Nowadays, Abrasive water jet (AWJ) machining is used in the manufacturing Industries as cutting, turning, milling and drilling processes. The application of this technology is further extended into polishing application. However, the cutting nature of the AWJ have produced the inappropriate surface conditions. Recently, the hybrid AWJ namely, Ultrasonic Assisted Abrasive Water Jet Polishing (UAAWJP) is mainly developed for polishing the complex shapes and the internal features of both metal and non-metals. Compared with other polishing technologies, UAAWJP has several advantages such as improvement in performance efficiency, higher kinetic energy, better surface quality, high precision, ease to control and absence of thermal distortions. The hybrid process is involved with variety of factors such as ultrasonic waves (frequency and vibration), abrasive particle type &size, jet pressure, traverse rate, abrasive mass flow rate, standoff distance, nozzle geometry, jet impact angle and processing time. However, the usage of conventional AWJ and UAAWJP techniques is scarce due to the lack of understanding of process mechanism and technical publications. It is mentioned that review article on AWJ polishing operations has not been published till date. Therefore, the present work is deals with the insights of previous studies on AWJ polishing and it advancements particularly in UAAWJP, and the results are presented with in view of process mechanism, features, benefits, effects and applications, and the results are also compared with other polishing techniques. The outcome of this study can also provide the better understanding and confident to the researchers and scientists on UAAWJP for further advancements and applications on it.

Parametric investigation and optimization of AWJM process on stir cast al7075/basalt composite materials using Taguchi based grey relational analysis

Optimization, one of the best techniques is used in various sectors of manufacturing to create the best manufacturing environment. It is one of the essential techniques adopted by industries for manufacturing their products with high quality at a lower cost. The aim of this research article is to explore and identify – the optimal set of Abrasive Water Jet Machining (AWJM) process and its parameters which includes nozzle abrasive jet pressure, Stand Off Distance and Traverse Speed. Disparities Such as Roughness of surface, and Cutting Width of Stir Cast AA7075/Basalt Composites strengthened with various levels of Basalt using abrasive flushing. Abrasive Jet Machine studied with L25 orthogonal assortment and the examination is carried out with Annova and Taguchi tools. Analysis of variance found the ideal levels of restrictions in Abrasive Jet Machine progression. The results obtained shows that Taguchi and ANNOVA is an operative technique for optimization of the machining restrictions for AWJM process.

Research on negative pressure jet dust-removal water curtain technology for coal mine cleaner production

There are serious pollution problems in the underground working environment of coal mines. To address this problem, a type of negative pressure jet dust-removal water curtain, based on the negative pressure jet dust-removal principle, was developed. Spray experiments were performed to obtain the macro-spray parameters of each nozzle, which were then used as parameters for CFD (computational fluid dynamics) modeling to numerically simulate the spray field. The influence of spray pressure Pw, nozzle type Tn, and the distance between the nozzle opening and the air suction port Ls, on the suction and purification effect and the spray field distribution law were studied. These studies determined that the air suction volume and spray field coverage effect were optimal when the parameter settings were Pw = 6 MPa, Tn:III, and Ls = 6 cm. Under such circumstances, the air suction volume of the dust hood was as high as 13.74 m3/min, and the proportion of the spray field with a cross-section concentration at the water curtain of more than 104 mg/m3 accounted for 92.4%. This dust reduction effect was physically measured in the air return roadway of the 117 fully mechanized mining face of Jinjitan Coal Mine. Using the optimal parameters obtained through numerical simulation, the concentration of respirable dust at measuring point C# was measured to be 0.179 mg/m3, equal to a dust reduction rate of 90.4%. This indicates that the application of a negative pressure jet dust-removal water curtain in large cross-section roadways can significantly reduce dust pollution levels.

Overview of the possibilities of surface modification of materials using energy beam technologies

Along with new trends, the manufacturing industry is also forced to move forward. Therefore, we focused on the use of Waterjet Peening technology - WJP. With the help of this technology, we can strengthen the material (harden) and remove residual stresses. This technology uses high pressure of water jet. Parameters also play an important role, namely the distance of the nozzle from the material being machined, the working pressure is standing, the feed rate, the number of cycles, etc. WJP technology is also promising from an ecological point of view, no harmful substances are formed during machining. Studies have also shown that, there are no heat affected zones during machining. When comparing the mentioned technology on samples made of surgical steel and titanium alloy, it was shown that the sample made of surgical steel showed greater signs of corrosion traces. Based on an experimental comparison of WJP technology and shot blasting technology, it is shown that the technologies achieved relatively the same results in terms of residual stress removal. A significant difference was found on the surface of the material, in the form of the degree of surface damage. With the help of WJP technology, the material did not reach such a roughness level as after shot blasting technology.

High-pressure flank cooling and chip morphology in turning Alloy 718

The use of cutting fluids is commonly considered a necessity while machining Heat Resistant Super Alloys (HRSA). Specifically, cutting fluids applied under high-pressure, which for many decades have been the solution for the most demanding applications. The results might be diverse and vary between applications, but typically leads to improved tool life, enhanced chip breakability, lower temperature in the cutting zone and better surface quality of the finished product. The available high-pressure cutting fluid delivery systems are usually designed with the intention to improve the cutting fluid penetration at the vicinity of the cutting edge on the rake face side of the insert. However, there has been limited interest in investigating high-pressure cutting fluid applied to its flank face. Both specifically and in combination with cutting fluid directed to the rake face. In this study, the focus has been to investigate the chip formation process during the turning of Alloy 718 (Inconel 718). Particularly, for a defined turning operation where high-pressure cutting fluid is applied to the flank side as well as the rake side of an uncoated carbide insert. Several combinations of pressure levels and jet directions were investigated. The corresponding effects on the tool-chip contact zone and chip characteristics were studied for two cutting speeds. The results of the investigation showed a substantial improvement in lowering the tool-chip contact area at a rake pressure of 16 MPa. At which pressure, additional cutting fluid applied to the flank at a moderate pressure of 8 MPa had no dominant effect on chip formation (chip break). However, flank cooling of the cutting zone supports chip segmentation and thus indirectly chip breakability. For cutting fluid applied to the rake side at a more moderate pressure of 8 MPa, more prominent effects on the insert became apparent when additional cutting fluid was applied to the flank side. This was particularly noticeable when cutting fluid was directed towards the flank side of the insert at the same pressure level as the cutting fluid applied towards its rake face. The additional thermal transfer was seen to have a significant effect on the material deformation phenomena in the primary shear zone (lowering shear angle) as well as the sliding and sticking conditions of the tool-chip interface. Based on the evidence from this study, it can be concluded that cutting fluid applied towards the flank side of the insert has a significant impact on the cutting process. In particular, if applied in combination with a rake pressure at a similar level, in this case, 8 MPa.

Investigation of the direct-flow jets vortex motion in the M-shaped boiler invert furnace

For advanced ultra-supercritical parameters (A-USC) of steam, the design of an M-shaped boiler is proposed, designed to operate in a 500 MW unit on a lean coal (grade TR). The boiler profile is selected from the condition of minimizing the length of the main steamlines made of expensive nickel-alloy steel. With regard to this boiler, a scheme has been developed for pulverized coal combustion in an invert furnace using direct-flow burners and nozzles. Research has been carried out on the physical model of the furnace in the implementation of this combustion scheme: a qualitative study of the trajectories of the burner jets, jets of secondary and tertiary air obtained by their hot spark visualization; quantitative determination of the main characteristics of burner jets and their weight gain. The studies have shown the high efficiency of the recommended scheme of the furnace-burner device: a staged supply of the oxidizer along the flame length and along the furnace height is organized; the dynamic pressure of jets on the furnace wall tubes is excluded; vortex furnace aerodynamics should provide a high degree of burnout of coal dust particles; air jets evenly fill the horizontal section of the furnace; the ejection capacity of turbulent jets is much higher than for a flat submerged jet.

Parametric investigation on surface roughness and hole quality of Ti metal hybrid fibers cored laminate (MFL) during abrasive water jet drilling

High-strength environment-friendly metal-fiber laminates (MFLs) are increasingly used for primary structures for various engineering applications. The surface roughness variation and delamination factor of a titanium (Ti) metal-cored basalt/flax fiber laminate were investigated during abrasive water jet drilling (AWJD). The present AWJD investigation is to establish the correlation of four important process independent variables of WJP—water jet pressure, TS—traverse speed, QMFR—abrasive mass flow rate, and SOD—stand-off distance to the delamination factor (Fd-top) and surface roughness (Ra) of drilled hole. Central composite design (CCD) of L29 orthogonal array was used to perform the experimental observations. The statistical approach (ANOVA) was employed to determine the contribution of individual AWJD parameters to drilling operation. It is identified from experimental results that the water jet pressure is the most predominant process parameter and its contribution on Fd-top and Ra were 74.28% and 72.48%, respectively. Increasing the water pressure from low (160 MPa) to its higher range (320 MPa) showed that the surface roughness and delamination factor were reduced irrespective of other drilling parameters. Increased water pressure provides enough kinetic energy for abrasive particles to facilitate a higher penetration potential during the drilling process. Scanning Electron Microscope (SEM) images show the machining-induced damages like ploughing marks, uncut fibers, ridges, craters, matrix smearing, and delamination on an abrasive water jet drilled surface of prepared MFL.

Complex shaped micro-channels generation using tools fabricated by AWJ milling process

Fabrication of complex shape micro-channels is a major challenge for manufacturing industries. Currently in commercial applications, lithography and non-conventional machining processes like lasers, electro-discharge machining (EDM) and chemical etching are commonly used for fabrication of these channels. In the present work, a novel Abrasive water jet (AWJ) milling based tool fabrication strategy has been proposed and implemented to make micro-tools (die/ electrode). The path strategy for jet movement is considered in a manner to selectively remove metal from a piece of material such that the resulting three-dimensional features become the required die shape that can be used as tool for the texturing process. Micro-tool of complex shape as fabricated on hard material (EN 31) sheet of 12 mm thickness and its geometry were analysed by controlling the step over (SO) distance. Hydraulic control based hard press contact texturing setup was developed to analyse the performance of such fabricated tools. Experiments were conducted on soft materials like, PMMA, Copper, Brass, aluminium and Nylon. Taper along the depth of the channels was observed because of the taper of the tool during fabrication. During fabrication, width of the tool less than 200 μ m was found wavi in nature as there was not enough backing material present to bear the side wise jet pressure of impinging jet. Buckling on the tools was observed with tool height greater than 1 mm.

LES Investigation of the noise characteristics of sheet and tip leakage vortex cavitating flow

In the present paper, cavitation noise induced by sheet cavity and tip leakage vortex cavity (TLVC) together generated by a NACA0009 hydrofoil are numerically investigated with Ffowcs Williams-Hawkings (FW-H) equations. Large eddy simulation (LES) combined with Schnerr-Sauer cavitation model is utilized and a satisfactory result is obtained as compared with the referenced experimental measurements. It is found that even though the volume of TLV cavity is much smaller than that of sheet cavity, their acoustic levels are comparable to each other. A close relationship is indicated between cavity evolutions and their radiated noises, which vary periodically for both sheet and TLV cavities. Moreover, intense sound pulses of pseudo-thickness and pseudo-loading noise are observed especially during the collapse process. It is indicated that the rise in far field pressure and action of the dilatation term inside the cavities may trigger the collapse of both kinds of cavities in the flow, resulting in sound impulses. It is worth mentioning that in agreement with previous investigations, high pressure distribution and jets at the ends of sub-TLVCs are noted to have a close relationship with the collapse of sub-TLVCs. Noise generated by sheet cavity is higher than that generated by TLV cavity at the dominant Strouhal number of 0.74, with relatively high values of both pseudo-thickness and pseudo-loading noises at the dominant Strouhal number. While noise of TLV cavitating flow has acoustic energy concentrated at either low Strouhal numbers or high Strouhal numbers for the two terms, respectively.

Experimental investigation on the erosion behaviors of frozen-thawed sandstone under abrasive supercritical CO2 jet impingement

An abrasive supercritical CO2 jet (ASJ) was used to erode sandstone subjected to freeze-thaw cycles and the erosion performance was investigated through laboratory experiments. The erosion characteristics of frozen-thawed and unfrozen sandstones under ASJ impingement at various jet temperature, jet pressure, and standoff distance were compared. It was found that the jet operating parameters shows very different effects on the two types of sandstones because of the fundamental differences in microstructure and mechanical properties. Frozen-thawed sandstones are more susceptible to erosion by ASJ impact due to the deterioration of rock physical properties under the periodic freeze-thaw cycles. Conical erosion craters are formed in unfrozen sandstones at all tested standoff distances, while at small standoff distances a regular deep hole is generated in the center of frozen-thawed sandstone with large pieces of rock peeled off around the hole due to jet pressurization. For both types of sandstones, the erosion depth decreases with the increase of jet temperature as the particle impact velocity decreases under the reduced drag force, and the decrease of kinetic energy and number of abrasives near the jet periphery at higher jet temperature results in smaller erosion area. There is a positive correlation between the size of erosion crater and the jet pressure, and the growth rate of frozen-thawed sandstone is much higher. SEM inspections reveal that frozen-thawed specimens show messy eroded surfaces with more diversified microstructural features. Sandstones are eroded predominantly by intergranular fracture, but the proportion of transgranular fracture increases with the increase of freeze-thaw cycle number.

Needle-free Mental Incisive Nerve Block:In vitro, Cadaveric, and Pilot Clinical Studies

The present study aimed to optimize Needle-Free Liquid Jet Injection (NFLJI) for Mental Incisive Nerve Blocks (MINB) and evaluate its clinical safety and feasibility. A MINB protocol was developed and optimized by series of NFLJI experiments in soft tissue phantoms and cadavers, then validated in two pilot Randomized Controlled Trials (RCT). The NFLJI penetration depth was found to be directly proportional to the supply pressure and volume. High-pressure NFLJIs (620 kPa or above) created maximum force and total work significantly greater than needle injections. Low-pressure NFLJIs (413 kPa), however, produced results similar to those of needle injections. Additionally, high-pressure NFLJIs created jet impingement pressure and maximum jet penetration pressure higher than low-pressure NFLJIs. Pilot RCTs revealed that high-pressure NFLJI caused a high risk of discomfort (60%) and paresthesia (20%); meanwhile, low-pressure NFLJI was less likely to cause complications (0%). The preliminary success rates of MINB from cadavers using NFLJIs and needles were 83.3% and 87.5%. In comparison, those from RCTs are 60% and 70%, respectively. To conclude, NFLJI supply pressure can be adjusted to achieve effective MINB with minimal complications. Furthermore, the cadaver study and pilot RCTs confirmed the feasibility for further non-inferiority RCT.

Parametric research on drag reduction and thermal protection of blunt-body with opposing jets of forward convergent nozzle in supersonic flows

Extreme drag and aerodynamic heat are the main penalties for blunt forebody of supersonic vehicles. This results in shorter flight range and higher fuel consumption, and aerodynamic heat seriously affects the performance of internal electronics. In the current study, the flow field mechanism of a blunt body model with a supersonic opposing jet in a supersonic flow field is numerically study. The physical model is a two-dimensional axisymmetric blunt forebody model with a convergent nozzle structure, and the numerical calculation model is a coupling of the two-dimensional axisymmetric Reynolds average method and the shear stress transport(SST) turbulence model. The calculation results in this paper are compared with the experimental data in the literature, which verifies the accuracy, and the calculation verifies the grid independence. An active flow control method that controls a single pressure parameter is proposed, and the formation process of the opposing jet in the convergent nozzle is considered, and the flow field structure of the opposing jet formed by the convergent nozzle with different nozzle sizes is studied. The results show that a single pressure parameter can control the formation of a supersonic opposing jet to form a long penetration mode and a short penetration mode. The ratio of the ambient pressure to the jet pressure at the stagnation point of the blunt body can directly affect the flow field structure of the opposing jet, and reasonable control of opposing jet parameters is an effective way for thermal protection and drag reduction of blunt body structures.

Gas Jet Coal-Breaking Behavior: An Elliptical Crushing Theoretical Model

Coalbed methane (CBM) is a source of clean energy and has been recovered in past decades all over the world. Gas dynamic disaster is the primary disaster in outburst coal, and methane drainage plays a key role in eliminating this danger. As an efficient technology, a gas jet is widely used in CBM development and methane drainage. In this work, the full impinging process of coal and rock fracturing by a supersonic gas jet was studied. To understand how jet parameters affect coal and rock fracturing results, an elliptical crushing theoretical model was proposed. In addition, a laboratory experiment was designed to examine the proposed model, and four key parameters affecting the fracturing results were studied. The results show that different from the monotonic variation of theoretical values, there is a turning point in the variation of experimental values under some parameters. Considering the influence of the depth and radius of the erosion pit, the rock-breaking effect is better when the nozzle size is 2.75 Ma. The optimal target distance is 30 mm, and the impact pressure of a gas jet should be continuously increased in order to achieve certain rock-breaking effects under the impact of the jet.

INFLUENCE OF THERMOPLASTIC PROCESSING PARAMETERS ON THEIR INTERNAL TEMPERATURE

With technological advances, polymers are increasingly used to manufacture various components that were previously exclusively manufactured with metals. One of the significant challenges in polymer processing is its relatively low thermal resistance, since relatively small temperature variations, especially when compared to metals and ceramics, lead to significant changes in material properties and in the final component geometry. This paper investigated how the internal temperature of polymers, subjected to an intermittent particulate jet deposition process in conjunction with a continuous flow of hot air, is affected by variation in surface roughness, polymer type, and air pressure. As the main result, low efficiency in heat transfer was caused by the combination of the convective nature of the heat exchange with the low thermal conductivity of the polymers. The variables with the most significant influence on the process were the intermittence and pressure of the particulate jet.

ANALYSIS OF ANALYTICAL MODELS OF VIBRATION DRIVE OF THE MACHINE FOR WASHING AND CLEANING BY PULSATING STREAM OF LIQUID AND EXPERIMENTAL RESEARCH OPERATING MODES

Two analytical models are proposed to describe the operation of the working body of the vibrating machine – a pulsation chamber with a nozzle to create a pulsating jet of liquid. The analysis of analytical models which describe change of parameters of a pulsating stream in a nozzle of a working body of the vibrating car for washing and cleaning of parameters of work of its drive and constructive dependences is carried out. The main factor in the process of washing and cleaning of contaminants is the speed of the jet or its maximum pressure when interacting with the contamination and the friction force of the flow when spreading on the surface to be cleaned. Experimental studies of the influence of the frequency of oscillations of the drive on the change of the maximum pressure of the pulsating jet at the nozzle section at certain design parameters using a sensor with recording equipment. As a result of experimental studies, it was found that the use of a diaphragm check valve, which connects the pulsation chamber with the bath for washing and cleaning, allows to increase the maximum pressure of the immersed pulsating fluid jet by reducing the volume of cavitation bubbles in the pulsation chamber liquid. This in turn allows you to increase the maximum pressure of the liquid jet from the nozzle. From the analysis of the results obtained from analytical models and experimentally presented on the comparative graph, the adjustment coefficients of analytical models are established, which were built with certain assumptions and complexity. The result of the experimental research is the recommendations for choosing the frequency range of the machine drive, which is from 14 to 16 Hz with a pulsation chamber diameter of 0.1 m, a nozzle diameter of 0.01 m and amplitude of oscillations of the drive of 0.002 m.

Research on bubble jet of underwater explosion at the bottom of fixed square plate

<p indent=0mm>The water jet formed after the collapse of the bubble in the near-field underwater explosion can cause serious damage to the local structure of the ship, and the formation of the jet is asymmetric, which makes it difficult to measure its data in the experiment. At present, studies on the pressure time history curves of the bubble jet in the underwater explosion are still relatively rare. In order to study the characteristics of the jet, the underwater explosion test of <sc>2.5 g</sc> TNT explosive at the bottom of fixed square plate at different detonation distances was carried out. First, the accuracy of the test data was verified by the underwater pressure sensor. Second, the image of the whole process from the explosive initiation to the bubble jet generated by the action of the bubble and the steel plate was obtained by high-speed camera. Finally, the time-history curve of water jet pressure was measured by the wall pressure sensor in the center of the steel plate, and another group of wall pressure sensors was set <sc>15 cm</sc> away from the center of the steel plate as a control group to ensure that the measured jet data were not clutter. The test data recorded by the underwater sensor show that the error between the shock wave overpressure, the maximum bubble radius of the bubble pulse period and the empirical formula is within 10%. The results recorded by the high-speed camera and wall pressure sensor show that three jets can be observed when the burst distance is <sc>28 cm,</sc> but the pressure time history curve is not measured due to the long burst distance. When the burst distances are <sc>15,</sc><sc> 17.5</sc> and <sc>20 cm,</sc> three jet pressure time history curves are measured. However, due to the short burst distance and the presence of a large number of bubbles between the steel plate and the water surface under the action of the shock wave, it is difficult to observe the test phenomenon with high-speed cameras. The pressure time history curve shows that three jets are generated after the first bubble pulse peak, and the jet pressure can reach 1/4 of the shock wave. The jet appears 1–3 ms after the first bubble pulse peak, and the time interval of each jet is between <sc>0.9</sc> and <sc>2.4 ms.</sc> The duration of jet load is between 4–27 μs, and it is greatly reduced as the distance increases.

Abrasive Machining Characteristics and Prediction Model for Sisal/Polyester Sandwich Composite

ABSTRACT This work focuses on optimization of abrasive machining parameters of the natural fiber reinforced sandwich composite, which is rarely reported in the literature. A sandwich made of vegetable fiber composite skins and polyvinyl chloride (PVC) foam of 80 gsm was machined for optimal conditions. The design of experiment and analysis were adopted to confirm the influence of machining parameters. The machining characters of bio-sandwich were compared with synthetic and hybrid sandwich panels to optimize the machinability of the target. The panels were manufactured through vacuum infusion bagging. The machining studies were done using the abrasive water jet cutting machine. The machining characteristics were optimized for the parameters and L18 Taguchi technique was employed in parameter optimization. Three controlled levels of machining parameters were chosen to be optimized: standoff distance (SOD), abrasive water jet pressure (JP), and nozzle traverse rate (TR). The response of kerf taper (KT), surface roughness (SR), and material removal rate (MRR) were investigated. It is observed that highest levels of these parameters gave minimum kerf taper and lowest levels produce lower surface roughness. The surface roughness and damage on the surface was observed using scanning electron microscopy (SEM). It Shows that flowing abrasive particle’s directional distortion noted at the foam regions due to their higher damping nature. The prediction model shows a good agreement with the experimental value.

Safety evaluations on unignited high-pressure methane jets impacting a spherical obstacle

Nowadays methane is a fossil fuel widely used both in industries and in civil appliances. From the safety point of view, due to its flammability, its use implies hazards for people and assets. The hazardous area related to a high-pressure jet of methane arising from an accidental loss of containment requires the estimation of the distance at which the methane concentration falls below the Lower Flammability limit. Such a topic is well covered in the literature when considering free jet conditions, i.e., jets that do not interact with any equipment or surface. The same cannot be said for high pressure jets impacting an obstacle. In this context, the present work focuses on studying high pressure methane jets impacting spherical obstacles by means of Computational Fluid Dynamics with the aim of giving some insights about such a jet-obstacle interaction, possibly providing a brief by-hand procedure that, only based on known scenario information, allows to estimate the maximum extent of the unignited high-pressure jet when interacting with a spherical obstacle.

Symulacja procesu pracy wgłębnych wirowych pomp strumieniowych

The article is devoted to the theoretical study of the operation process of the borehole ejection system as part of the tubing string, jet pump and packer installed below; the system implements the hydrojet method of oil well operation. The improved design of the jet pump contains inclined guiding elements placed in its receiving chamber for swirling the injected flow, which results in an increase in the efficiency of the borehole ejection system. Based on the law of conservation of liquid momentum in the mixing chamber of the jet pump and taking into account the inertial pressure component caused by the swirling of the injected flow, there is obtained the relative form of the equation of the ejection system pressure characteristic, the structure of which contains a component that determines the value of the additional dynamic head. According to the results obtained, the additional dynamic head caused by swirling of the injected flow is determined by the ratio of the geometric dimensions of the flow path of the jet pump, the angle of inclination of the elements for creating vortex flows, and the ratio of the power and reservoir fluids. In the case of asymmetric swirling of the injected flow, an increase in the value of the relative displacement of the jet pump decreases the value of the additional dynamic pressure. In order to study the effect of flow swirling on the energy characteristic of the ejection system, the pressure characteristic of the jet pump was transformed into the dependence of its efficiency on the injection coefficient. Jet pump models with the ratio of the cross-sectional areas of the mixing chamber and the nozzle of 5.012 and 6.464, respectively, were used to check the adequacy of the theoretical pressure and energy characteristics obtained during the simulation of the performance process of the concentric ejection system. The average error in the theoretical determination of the pressure and efficiency of the vortex jet does not exceed 8.65% and 6.48%, respectively.