scholarly journals The Improvement of the Mathematical Model of the Work Process of Borehole Ejection Systems

2020 ◽  
pp. 36-44
Author(s):  
Ye. І. Kryzhanivskyi ◽  
D. О. Panevnyk
Keyword(s):  
Mathematical Models ◽  
Flow Rate ◽  
Hydraulic System ◽  
Pressure Ratio ◽  
Energy Performance ◽  
Maximum Efficiency ◽  
Relative Pressure ◽  
Jet Pump ◽  
Relative Flow Rate ◽  
Relative Flow

The article presents the sequence of deriving the equations which characterize the hydraulic system of jet pumps that carry out suction and injection-suction bottom flushing while drilling the production wells. The nature of flow distribution in the borehole ejection systems of the suction and injection-suction types is analyzed. The analysis is carried out taking into consideration the peculiarities of the calculation of branched hydraulic systems. While studying the movement of the flows in the bottom circulation circuits, the authors take into account the equation of the balance of the flow-rate at nodal points and hydraulic losses in parallel parts of the system. The developed mathematical models are based on the study of the changes in hydrodynamic pressures which occur in characteristic sections of a jet pump. The pressure ratio of mixed, injected and operating flows is presented as non-dimensional relative pressure of the ejection system. The dependence of non-dimensional relative pressure on the relative flow rate determines the characteristic of the hydraulic system of a jet pump. The relative flow rate or injection ratio of a jet pump is defined as the ratio of flow rate to injected and work flow. While analyzing the developed mathematical models, the authors specify the relation between the design and operating parameters of a jet pump. These parameters ensure its operation with maximum efficiency. Based on the study of the influence of the correlation between the diameters of the jet pump nozzles and the flushing system of the bit, the authors specify parameters which are optimal in terms of energy performance. The article provides the example of graphical determination of the operating point of a pumping unit. This determination is based on a simultaneous solution of the equations of the characteristics of the jet pump and the hydraulic system in which it operates. The improved techniques allow to predict the mode parameters of ejection systems and to determine the size of flowing part of the jet pump. They provide maximum energy performance of its workflow.

scholarly journals Optimization of design and mode parameters of the well ejection system

2020 ◽  
pp. 73-80
Author(s):  
Ye. I. Kryzhanivskyy ◽  
D. O. Panevnyk
Keyword(s):  
Geometric Parameter ◽  
Energy Performance ◽  
Maximum Efficiency ◽  
Relative Pressure ◽  
Drilling Speed ◽  
Jet Pump ◽  
Mixing Chamber ◽  
Jet Pumps ◽  
Injection Ratio ◽  
Pressure Characteristics

Insufficient energy performance of ejection equipment and a high probability of non-operating modes of its operation reduce the efficiency of downhole jet pumps. The method of determining the design and operating parameters of the well ejection system, which provide the maximum efficiency of the jet pump, is presented.  The proposed algorithm for determining the optimal values of the geometric dimensions of the flowing part of the jet pump involves the construction of a series of pressure characteristics for different values of its geometric parameter, the calculation of the efficiency and the determination of the injection ratio and the relative pressure corresponding to its maximum values.  During the studies, the main geometric parameter of the jet pump varied in the range from 2 to 6, given that these geometric dimensions are used in jet devices common in the oil industry. The optimal dimensions of the current part of the jet pump are obtained in the process of studying its pressure characteristics, and the optimal dimensions of the washing system of the bit - in the process of studying the characteristics of the hydraulic system. The design of an at-bit ejection system, which allows to increase the mechanical drilling speed, the passage of the bit, to stabilize the moment on the bit, to reduce its level of vibration and to control the antiaircraft angles of the well is considered. The efficiency of using at-bit jet pumps is in the following: an increase in the mechanical drilling speed up to 18.7%, the passage of the bit up to 50.8%. The research established the optimal diameters of the working nozzle, mixing chamber and bit nozzles, the distance between the working nozzle and the mixing chamber, the injection ratio and the relative pressure of the at-bit jet pump. The obtained values ​​of design and mode parameters exclude the occurrence of cavitation modes of operation of the ejection system and allow the operation of jet pumps with maximum efficiency.

scholarly journals Increase fish protective efficiency constructions of meliorative water intake

2020 ◽  
pp. 69-73
Author(s):  
Svetlana Mikhailovna Dragunova ◽  
Yevgeniy Vladimirovich, Кuznetsov ◽  
Anna Yevgenievna Khadzhidi
Keyword(s):  
Physical Model ◽  
Water Intake ◽  
Flow Rate ◽  
Juvenile Fish ◽  
Protective Efficiency ◽  
Irrigation Systems ◽  
Relative Flow Rate ◽  
Reclamation System ◽  
Relative Flow ◽  
Fish Protection

The article solves the problem of increasing the level of protection of juvenile fish to a standard indicator by the modernization of individual elements of fish protection of ameliorative water intake of irrigation systems. The design of an integrated fish-protecting structure with a logging boom adapted to hydrology and the rhythm of migration of juvenile fish from irrigation sources has been proposed. The results of studies on a physical model, taking into account the costs of the reclamation system, show an increase in the efficiency of the combined fish protection structure with a harbor for reclamation water intakes in the range of 78,5–84,0 %, depending on the relative flow rate on the shelf of the sanctuary.

The effect of repeated cold exposure of the hand on the reactivity of digital vessels

1969 ◽  
Vol 47 (3) ◽  
pp. 261-265 ◽  
Author(s):  
Peter Gaskell ◽  
Kathleen L. Long
Keyword(s):  
Blood Flow ◽  
Flow Rate ◽  
Cold Exposure ◽  
Opening Pressure ◽  
Relative Flow Rate ◽  
Opposite Hand ◽  
Critical Opening ◽  
Before And After ◽  
Relative Change ◽  
Relative Flow

One hand of each of 10 subjects was immersed in stirred water at 4 °C for 1 h per day, 5 days per week, for 3 weeks, to produce local acclimatization to cold. The opposite hand was immersed at the same time in water at 32 °C. The reactivity of digital vessels in a finger of each hand was measured as the increase in the critical opening pressure of the vessels in response to an intravenous infusion of noradrenaline at 2 and 5 μg/min. The reactivity of digital vessels in the test hand was compared with that in the control hand both before and after the repeated cold exposure of the test hand to see whether the cold exposure altered the reactivity of vessels in the test hand relative to that in the control hand. No evidence of such a relative change was obtained. Resting blood flow at 21 and 32 °C in the test hand was compared with that in the control hand both before and after the repeated cold exposure. No change in the relative flow rate in the two hands was observed as a result of the cold exposure. Roentgen studies of the hands did not reveal any effect of the repeated cold exposure on the mineralization of the bones of the hands.

scholarly journals Investigation of Low-Temperature Lean Combustion Characteristics in Power Plants with External Heating of Components

2021 ◽  
Vol 2(50) ◽  
Author(s):  
Nikolay Bachev ◽  
◽  
Alena Shilova ◽  
Oleg Matyunin ◽  
Oksana Betinskaya ◽  
...  
Keyword(s):  
Low Temperature ◽  
Combustion Chamber ◽  
Flow Rate ◽  
Turbulent Combustion ◽  
Power Plants ◽  
Lean Combustion ◽  
Relative Flow Rate ◽  
External Heating ◽  
Low Emission ◽  
Relative Flow

An integral part of any open-type gas turbine plant is a low-emission combustion chamber, which is usually two-zone and cooled. One of the ways to reduce emission of harmful substanc-es is organizing low-emission low-temperature lean combustion with external heating of compo-nents. This paper investigates the effect of external heating of air and fuel gas on expansion of the lower combustion limit and stable flame position in a single-zone uncooled combustion chamber of a microgas turbine power plant. Stable position of the flame front in combustion chambers of this type mainly depends on the ratio between the average flow rate of the combus-tible-air mixture and the rate of turbulent combustion. This ratio depends on thermal, gas-dynamic, thermochemical and geometric factors. The purpose of this work is to substantiate the possibility of using the relative flow rate as a generalized characteristic. This goal was achieved in processing a large amount of published experimental data and numerical modeling of low-temperature combustion of lean mixtures. The most significant research result is determination of the range of relative flow rate (gk = 0.3…3.5·10-4 kg⁄s∙N), at which it is possible to ensure sta-ble flame position in a single-zone combustion chamber. Significance of the obtained results lies in the fact that using the relative flow rate makes it possible to quickly determine and analyze the geometric and gas-dynamic parameters and characteristics of turbulent combustion in com-bustion chambers of micro-gas turbine power plants.

scholarly journals Сontrol and Regulation of the Hydraulic Jet Pump Operation Mode

2020 ◽  
pp. 18-25
Author(s):  
D. O. Panevnyk ◽  
O. V. Panevnyk
Keyword(s):  
Remote Control ◽  
Flow Rate ◽  
Hydraulic System ◽  
Operation Mode ◽  
Operating Point ◽  
Jet Pump ◽  
Mixed Flow ◽  
Binary Diagram ◽  
Circulation Circuit ◽  
Pumping Unit

Permanent monitoring and remote control of the operation mode of the hydraulic jet pump allows increasing the efficiency of the hydrajet mode of oil wells operation. Based on the analysis of the workflow of the ejection system, the authors reveal the relation between the density and flow rate of the mixed flow and the operating parameters of the oil hydraulic jet pump in the form of nonlinear dependencies, which make it possible to carry out remote control over the flow rate in the bottomhole circulation circuit. In the process of modeling the hydraulic relations between the elements of the ejection system, a binary diagram is constructed. This binary diagram is created in the form of two combined quadrants and presents the obtained regularities between the parameters of the mixed flow at the well outlet and the operation mode of the jet pump. The authors present the method of remote control over the operation mode of a well ejection system by means of varying the flow-rate of power fluid directed to the well by a ground pump unit and by means of changing the dimensions of the components of the flowing part of the jet pump. The regulation of the operation mode of the hydraulic jet pump occurs by changing the position of the operating point of the pumping unit. In the process of regulating the operation mode of the jet pump by changing the operating flow rate, the authors obtain a series of characteristics of the hydraulic system which determine the coordinates of the operating point of the pumping unit. Adjusting the operation mode of the ejection system by changing the dimensions of the components of the flowing part of the jet pump involves creating a series of its own characteristics with constant characteristics of its hydraulic system. The replacement of the components of the flowing part of the jet pump is carried out in a hydraulic way and does not require round-trip operations in the well. The authors present the graphical interpretation of the proposed methods of regulating the operation mode of the well ejection system in the form of combined characteristics of the jet pump and its hydraulic system built in the single system of coordinates.

scholarly journals Biological treatment of drippers clogged by the use of treated domestic wastewater

2016 ◽  
Vol 20 (7) ◽  
pp. 595-599
Author(s):  
Danniely O. Costa ◽  
Rafael O. Batista ◽  
Hudson S. M. Vale ◽  
Amanda B. de Sousa ◽  
Solange A. G. Dombroski ◽  
...  
Keyword(s):  
Flow Rate ◽  
Biological Treatment ◽  
Statistical Difference ◽  
Domestic Wastewater ◽  
Rate Reduction ◽  
Relative Flow Rate ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
Different Doses ◽  
Relative Flow

ABSTRACT This study aimed to recover the flow rate of clogged drippers with different doses and permanence times of the product MaxBio. The experiment was conducted in a completely randomized design in split-split-plot scheme, where the plots corresponded to product doses (80, 160, 240 and 320 mg L-1), subplots to the applied treatments (T1 - without biological treatment, T2 - 1st application of the product, and T3 - 2nd application of the product) and in sub-subplots the types of emitters (Plastro Hydrodrip Super, Netafim Tiran and Netafim PCJ-CNJ), with three replicates. The four irrigation units operated with treated domestic wastewater for 400 h in order to clog the emitters. After applying the product MaxBio, the flow rate of the drippers and the relative flow rate reduction were determined to express the unclogging levels. There was significant effect of T2 and T3 on the recovery of the flow rate of the drippers, while for the reduction of relative flow rate, the doses of the product did not show statistical difference regarding the types of drippers.

scholarly journals EFFECT OF OXIDANT RELATIVE FLOW RATE ON OBTAINING RAW MATERIAL FOR PULVERIZED COAL PRODUCTION FROM HIGH-SULFURIC LOW GRADE COAL

2017 ◽  
Vol 11 (2) ◽  
pp. 236-241 ◽  
Author(s):  
Mariіa Shved ◽  
◽  
Serhiy Pyshyev ◽  
Yuriy Prysiazhnyi ◽  
◽  
...  
Keyword(s):  
Flow Rate ◽  
Pulverized Coal ◽  
Raw Material ◽  
Low Grade ◽  
Coal Production ◽  
Relative Flow Rate ◽  
Relative Flow

scholarly journals Improving the Energy Efficiency of the Use of Borehole Jet Pumps

2020 ◽  
Vol 63 (5) ◽  
pp. 462-471
Author(s):  
D. A. Panevny ◽  
A. V. Panevny
Keyword(s):  
Cross Sections ◽  
Hydraulic System ◽  
Gas Flow ◽  
Oil And Gas ◽  
Successive Approximations ◽  
Maximum Efficiency ◽  
Method Of Successive Approximations ◽  
Jet Pump ◽  
Software Environment ◽  
Installation Depth

The article presents rationales for choosing the depth of installation of an oil jet pump in the borehole that which ensures maximum efficiency of its operation. The operating parameters of the ejection system are determined by the joint solution of the characteristic equations of the high-pressure jet pump and the hydraulic system. In the process of solving the system of equations, the method of successive approximations, the Delphi software environment and PTC Mathcad resources were used. The equation of the characteristics of the jet pump hydraulic system was obtained by determining the pressures in its distinctive cross-sections and then presenting their values as the relative (dimensionless) head of the ejection system. Alteration the installation depth of the jet pump changes the characteristics of its hydraulic system, the parameters of the operating point of the pumping unit and its efficiency. In this case, the minimum permissible installation depth of the jet pump is determined by the value of the minimum pressure in the elements of the ejection system, which must exceed the value of the elastic pressure of saturated vapors of the oil and gas flow and ensure its operation in pre-cavitation mode. The probability of operation of a jet pump in cavitation mode was studied using the Bernoulli, Darcy – Weisbach and flow continity equations. The inversely dependence of the ejection coefficient and efficiency of the jet pump on the depth of its installation in the borehole has been revealed. If the jet pump is installed in the borehole at the optimal depth, its efficiency is increased by 30 %.

Investigation of Hydrodynamic Focusing in a Microfluidic Coulter Counter Device

2012 ◽  
Vol 134 (8) ◽  
Author(s):  
Muheng Zhang ◽  
Yongsheng Lian ◽  
Cindy Harnett ◽  
Ellen Brehob
Keyword(s):  
Flow Field ◽  
Flow Rate ◽  
Coulter Counter ◽  
Hydrodynamic Focusing ◽  
Relative Flow Rate ◽  
Advection Diffusion Equation ◽  
Sample Stream ◽  
Voltage Signal ◽  
The Impact ◽  
Relative Flow

The Coulter technique enables rapid analysis of particles or cells suspended in a fluid stream. In this technique, the cells are suspended in an electrically conductive solution, which is hydrodynamically focused by nonconducting sheath flows. The cells produce a characteristic voltage signal when they interrupt an electrical path. The population and size of the cells can be obtained through analyzing the voltage signal. In a microfluidic Coulter counter device, the hydrodynamic focusing technique is used to position the conducting sample stream and the cells and also to separate close cells to generate distinct signals for each cell and avoid signal jam. The performance of hydrodynamic focusing depends on the relative flow ratio between the sample stream and sheath stream. We use a numerical approach to study the hydrodynamic focusing in a microfluidic Coulter counter device. In this approach, the flow field is described by solving the incompressible Navier-Stokes equations. The sample stream concentration is modeled by an advection-diffusion equation. The motion of the cells is governed by the Newton-Euler equations of motion. Particle motion through the flow field is handled using an overlapping grid technique. A numerical model for studying a microfluidic Coulter counter has been validated. Using the model, the impact of relative flow rate on the performance of hydrodynamic focusing was studied. Our numerical results show that the position of the sample stream can be controlled by adjusting the relative flow rate. Our simulations also show that particles can be focused into the stream and initially close particles can be separated by the hydrodynamic focusing. From our study, we conclude that hydrodynamic focusing provides an effective way to control the position of the sample stream and cells and it also can be used to separate cells to avoid signal jam.

scholarly journals STUDY ON CHARACTERISTICS OF A DOWNHOLE VORTEX JET PUMP

2021 ◽  
Vol 2(73) (2) ◽  
pp. 22-32
Author(s):  
Denis Panevnyk ◽  
Keyword(s):  
Swirling Flow ◽  
Dynamic Pressure ◽  
Relative Pressure ◽  
Technological Parameters ◽  
Jet Pump ◽  
Cross Sectional ◽  
Flow Rates ◽  
Relative Flow Rate ◽  
Mixing Chamber ◽  
Jet Pumps

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.

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