scholarly journals DEVELOPMENT AND BENCH TESTS OF A PHYSICAL MODEL OF REVERSIBLE HYDRAULIC IMPACT DEVICE

2021 ◽  
Vol 2 (3) ◽  
pp. 180-188
Author(s):  
Leonid V. Gorodilov ◽  
Vitaly G. Kudryavtsev ◽  
Alexey I. Pershin
Keyword(s):  
Physical Model ◽  
Flow Rate ◽  
Test Bench ◽  
Body Movement ◽  
Bench Tests ◽  
Operating Modes ◽  
Hydraulic Impact ◽  
Impact Device

The paper presents a physical model of reversible one-way hydraulic impact device (with two striker movement limiters). The researches helped to develop the design of the device and a test bench simulating the resistance of the medium in case of possible body movement. Tests of a hydraulic impact device with a rigidly sealed body showed its efficiency in the operating modes obtained in the calculations: when changing the flow rate of the liquid, the striker strikes both in the forward and reverse directions.

Certification principles for reproduction of multiphase test bench flow-rate

2018 ◽  
pp. 13-18
Author(s):  
V.N. Petrov ◽  
◽  
F.M. Galimov ◽  
O.K. Borisova ◽  
S.V. Petrov ◽  
...  
Keyword(s):  
Flow Rate ◽  
Test Bench

Computational and theoretical research of the injector block function

2020 ◽  
pp. 123-126
Author(s):  
В.В. Кожемякин ◽  
Р.А. Иванов ◽  
Е.С. Игнатьева
Keyword(s):  
Hydraulic Resistance ◽  
Cross Section ◽  
Flow Rate ◽  
Pressure Dependence ◽  
Theoretical Study ◽  
Water Jet ◽  
Theoretical Research ◽  
Sudden Expansion ◽  
Operating Modes ◽  
Coefficient Of Hydraulic Resistance

Работа посвящена расчетно-теоретическому исследованию работы блока инжекторов. Рассмотрен пароводяной струйный аппарат, который применяется в качестве средства циркуляции теплоносителя первого контура. Подвод дополнительного потока осуществляется на цилиндрическом участке с внезапным расширением сечения через перемычку. Для достижения поставленной цели разработана программа для ЭМВ, в которой смоделирована зависимость давления от нагрузки в контуре, а также проведено расчетно-теоретическое исследование влияние гидравлического сопротивления на расход перемычки. В данной работе рассмотрены только рабочие режимы, т.е. все инжекторы работают как насосы. В ходе работы было установлено, что при нагрузке в 30% увеличиваются коэффициенты инжекции пароводяного струйного аппарата, но характер работы перемычек не меняется. Так же было установлено, что расход через перемычку меняется не пропорционально коэффициенту гидравлического сопротивления перемычки. The paper is devoted to the computational and theoretical study of the injector block operation. A steam-water jet apparatus is considered, which is used as a means of circulating the primary circle coolant. The additional flow is supplied on the cylindrical section with a sudden expansion of the cross-section through the bridge. To achieve this goal, a computer program was developed that modeled the pressure dependence on the load in the circuit, and also a theoretical study of the influence of hydraulic resistance on the flow of the jumper was conducted. In this paper, only operating modes are considered, i.e. all the injectors function as pumps. In the process of the research, it was found that at a load of 30%, the injection coefficients of the steam-water jet apparatus increase, but the nature of the work of the jumpers does not change. It was also found out that the flow rate through the jumper does not change in proportion to the coefficient of hydraulic resistance of the jumper.

Pitfalls for Accurate Steady-State Port Flow Simulations

2012 ◽  
Author(s):  
Xiaofeng Yang ◽  
Zhaohui Chen ◽  
Tang-Wei Kuo
Keyword(s):  
Steady State ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Measured Data ◽  
Steady State Flow ◽  
Bench Tests ◽  
Flow Simulations ◽  
Mesh Topology ◽  
State Flow

Steady-state port flow simulations were carried out with a commercial three dimensional (3D) Computational Fluid Dynamics (CFD) code using Cartesian mesh with cut cells to study the prediction accuracy. The accuracy is assessed by comparing predicted and measured mass-flow rate and swirl and tumble torques at various valve lifts using different boundary condition setup and mesh topology relative to port orientation. The measured data is taken from standard steady-state flow bench tests of a production intake port. The predicted mass-flow rates agree to within 1% with the measured data between the intermediate and high valve lifts. At low valve lifts, slight over prediction in mass-flow rate can be observed. The predicted swirl and tumble torques are within 25% of the flow bench measurements. Several meshing parameters were examined in this study. These include: inlet plenum shape and outlet plenum/extension size, embedded sphere with varying minimum mesh size, finer meshes on port and valve surface, orientation of valve and port centerline relative to the mesh lines. For all model orientations examined, only the mesh topology with the valve axis aligned closely with the mesh lines can capture the mass-flow rate drop for very high valve lifts due to flow separation. This study further demonstrated that it is possible to perform 3D CFD flow analyses to adequately simulate steady-state flow bench tests.

scholarly journals COMPOSIÇÃO DE PERFIS RADIAIS DE DISTRIBUIÇÃO DE ÁGUA DE ASPERSORES

Irriga ◽  
2009 ◽  
Vol 14 (1) ◽  
pp. 41-53 ◽  
Author(s):  
Giuliani Do Prado ◽  
Alberto Colombo
Keyword(s):  
Key Words ◽  
Flow Rate ◽  
Linear Relation ◽  
Water Distribution ◽  
Test Bench ◽  
Application Rate ◽  
Water Application ◽  
Irrigation Uniformity ◽  
Nozzle Configuration ◽  
Composition Process

COMPOSIÇÃO DE PERFIS RADIAIS DE DISTRIBUIÇÃO DE ÁGUA DE ASPERSORES  Giuliani do Prado; Alberto ColomboDepartamento de Engenharia, Universidade Federal de Lavras, Lavras, MG, [email protected]  1 RESUMO Este trabalho descreve um procedimento de composição do perfil radial de aspersores que operam com dois bocais. Foram determinados na bancada de ensaios de aspersores da Universidade Federal de Lavras, em Lavras/MG, os valores de vazão e perfil radial do aspersor PLONA-RL250 operando, individualmente, com os bocais principais 14 e28 mme com os bocais auxiliares 5, 6 e7 mm, e operando, nas diferentes seis combinações de bocal auxiliar e principal do aspersor, sob cinco pressões de serviço (292, 392, 490, 588 e 696 kPa). No processo de composição do perfil radial realizado, ajustando a vazão dos bocais auxiliar e principal, operando individualmente, a vazão do aspersor operando com o conjunto de bocais auxiliar e principal, verificou-se um coeficiente de determinação médio de 88,57% entre as intensidades de precipitação adimensionais dos perfis radiais compostos com os perfis radiais do conjunto. Na relação linear, ajustada, entre os valores de uniformidade de equipamentos autopropelidos de irrigação, obtidos com os perfis radiais compostos e do conjunto, a inclinação da reta foi igual a 44°12’com um erro relativo médio de 2,34%. Estes resultados mostram que o procedimento de composição do perfil radial de aspersores não influencia, de maneira significativa, na uniformidade de aplicação de água de aspersores. UNITERMOS: bocais do aspersor, vazão do aspersor, uniformidade de irrigação.  PRADO, G. DO; COLOMBO, A. SPRINKLER WATER DISTRIBUTION COMPOSITIONS  2 ABSTRACT This paper described a procedure to compose a sprinkler pattern for a sprinkler that operates with two nozzles. To compose the pattern, discharge values and patterns of the PLONA-RL250 sprinkler were determined at the sprinkler test bench of the Universidade Federal de Lavras, in Lavras/MG. The tests were conducted with all possible combinations using 14mm and28 mmmain nozzles and the 5, 6 and7 mmauxiliary nozzles as well as with each nozzle functioning individually. Five working pressures (294, 392, 490, 588 and 686 kPa) were used for each nozzle configuration. In the pattern composition process, by adjusting the main and auxiliary nozzle discharges operating individually, and by adjusting  the sprinkler discharge operating with the corresponding pair of main and auxiliary nozzles, it was verified that the average determination coefficient was 88.57% between the dimensionless water application rate of the composed and pair patterns. In the adjusted linear relation, between the uniformity values of a travel irrigation machine obtained from the composed and pair patterns, the inclination was 44° 12' with an average relative error of 2.34%. These results show that the procedure to compose a sprinkler pattern for sprinklers does not influence significantly the water application uniformity of sprinklers. KEY WORDS: sprinkler nozzles, sprinkler flow rate, irrigation uniformity

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.

Research on Powder Stream of Coaxial Powder Feeding in Laser Manufacturing Technology

2013 ◽  
Vol 423-426 ◽  
pp. 807-810
Author(s):  
Heng Quan ◽  
Yun Shan Wang ◽  
Li Feng Liu ◽  
Shao Jun Liu ◽  
Qing Ruo Meng
Keyword(s):  
Physical Model ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Concentration Field ◽  
Ccd Camera ◽  
Factors Affecting ◽  
Coaxial Nozzle ◽  
Powder Mass ◽  
Powder Feeding

Mathematical-physical model of powder stream in coaxial powder feeding was established. The concentration fields of powder stream of coaxial nozzle of different size and powder mass flow rate were analyzed. The concentration field and morphology of the powder stream were detected by CCD camera. The results show that the size of coaxial nozzle and powder mass flow rate are major factors affecting the powder stream. The mathematical-physical model and experimental data provide theoretical basis for laser cladding manufacturing.

scholarly journals Cavitation in swirling flows of hydraulic spillways

2019 ◽  
Vol 91 ◽  
pp. 07022
Author(s):  
Genrikh Orekhov
Keyword(s):  
Flow Rate ◽  
Vortex Flow ◽  
Structural Elements ◽  
Flow Energy ◽  
Operating Modes ◽  
Swirl Angle ◽  
Energy Dissipators ◽  
High Head ◽  
The Impact

During operation of high-head hydraulic spillway systems, cavitation phenomena often occur, leading to destruction of structural elements of their flow conductor portions. The article is devoted to the study of erosion due to cavitation in the circulation flows of eddy hydraulic spillways, including those equipped with counter-vortex flow energy dissipators. Cavitation destructive effects depend on many factors: intensity consisting in the rate of decrease in the volume or mass of a cavitating body per unit of time, the stage of cavitation, geometric configuration of the streamlined body, the content of air in water, the flow rate, the type of material. The objective of the study consisted in determination of cavitation impacts in circulating (swirling) water flows. The studies were conducted by a method of physical modeling using high-head research installations. Distribution of amplitudes of pulses of shock cavitation impact is obtained according to the frequency of their occurrence depending on the flow velocity, the swirl angle, the height of the cavitating drop wall and the stage of cavitation. The impact energy depending on the stage of cavitation and the flow rate is given for different operating modes of the counter-vortex flow energy dissipators of a hydraulic spillway. In the conclusions, it is noted that cavitation impacts in the circulation flows occur mainly inside the flow, which is a fundamental difference from similar processes in axial flows.

Modeling of Single Flow Zinc-Nickel Battery for System Efficiency Improvement

2014 ◽  
Vol 716-717 ◽  
pp. 94-97
Author(s):  
Yan Xue Li ◽  
Ming Chui Dong ◽  
Peng Cheng Zhao ◽  
Ying Duo Han
Keyword(s):  
Pump Power ◽  
Flow Rate ◽  
The Novel ◽  
System Efficiency ◽  
Electrolyte Flow ◽  
Battery System ◽  
Operating Modes ◽  
Power Part ◽  
Single Flow ◽  
Zinc Nickel

In operating of a flow battery, a certain flow rate should be maintained in order to guarantee its performance. But the pump consumed power may cause significant losses for the overall battery system. In this paper, a fresh electrical model is proposed for the novel single flow zinc-nickel battery. The model consists of both battery stack part and pump power part, which consequently not only predicts accurately the battery electrical output, but also estimates the pump consumed power at different electrolyte flow rate. Based on the validated model, the influence of pump power on flow battery’s system efficiency can be evaluated at different operating modes. At last, possible means to further improve the system efficiency of battery is discussed.

Establishing Mine Water Supply Network Physical Model Based on the Abnormal Similar Theory

2013 ◽  
Vol 421 ◽  
pp. 850-854
Author(s):  
Zhong An Jiang ◽  
Lei Lei Shi ◽  
Pei Wang
Keyword(s):  
Water Supply ◽  
Physical Model ◽  
Flow Rate ◽  
Mine Water ◽  
Similarity Criterion ◽  
Mine Safety ◽  
Supply Network ◽  
Water Supply Network ◽  
Safety Regulations ◽  
Similar Theory

It’s necessary to establish a perfect dust water supply system according to Coal mine safety regulations. In order to do researches on the reliability of mine dust water supply network, this paper deduces the similarity number of flow rate and pressure under the condition of abnormal similarity, and establish the physical model of mine water supply network according to the gravity similarity criterion at first in lin-nan mine as the background. Monitor the running status of the whole network, measure the flow rate and pressure of the monitoring stations, and then contrast the experiment result and EPANETH simulation result with the data of the original network. The results show that physical model meets gravity similarity under the condition of abnormal similarity, which provides the experimental basis for the follow-up research on mine water supply network.

scholarly journals Mining Linguistic Associations for Emergent Flood Prediction Adjustment

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Michal Burda ◽  
Pavel Rusnok ◽  
Martin Štěpnička
Keyword(s):  
Physical Model ◽  
Flow Rate ◽  
Water Flow Rate ◽  
Physical Models ◽  
Time Shift ◽  
Flood Prediction ◽  
Fuzzy Association Rules ◽  
Flood Peak ◽  
Expected Time ◽  
Parameter Estimations

Floods belong to the most hazardous natural disasters and their disaster management heavily relies on precise forecasts. These forecasts are provided by physical models based on differential equations. However, these models do depend on unreliable inputs such as measurements or parameter estimations which causes undesirable inaccuracies. Thus, an appropriate data-mining analysis of the physical model and its precision based on features that determine distinct situations seems to be helpful in adjusting the physical model. An application of fuzzy GUHA method in flood peak prediction is presented. Measured water flow rate data from a system for flood predictions were used in order to mine fuzzy association rules expressed in natural language. The provided data was firstly extended by a generation of artificial variables (features). The resulting variables were later on translated into fuzzy GUHA tables with help of Evaluative Linguistic Expressions in order to mine associations. The found associations were interpreted as fuzzy IF-THEN rules and used jointly with the Perception-based Logical Deduction inference method to predict expected time shift of flow rate peaks forecasted by the given physical model. Results obtained from this adjusted model were statistically evaluated and the improvement in the forecasting accuracy was confirmed.

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