scholarly journals Methods of studying the characteristics of hydraulic systems of loading machines on a laboratory hydraulic stand

2018 ◽  
Vol 239 ◽  
pp. 04006
Author(s):  
Yuri Ezhov ◽  
Igor Zub ◽  
Natalia Pizhurina ◽  
Vladimir Sidorenko
Keyword(s):  
Pressure Dependence ◽  
Hydraulic System ◽  
Laboratory Work ◽  
Hydraulic Systems ◽  
Operating Modes ◽  
Hydraulic Devices ◽  
Selection Of

The operation of loading machines requires special attention in the selection of materials for hydraulic devices and the development of recommendations for their operation. Competencies that should be obtained by a specialist operating the handling equipment, include the ability to analyze the operation of the hydraulic system on the basis of these devices and adjust the operating modes of the handling devices. In this paper, a number of experiments on the hydraulic bench. During the experiments, the characteristics of the pressure dependence in the lifting cylinder on the weight of the load and the lifting angle were removed. The considered algorithm of research can be used in the development of methods of laboratory work for the training of specialists in the field of operation and design of loading equipment.

Calculation of a closed hydraulic volumetric system

2021 ◽  
pp. 27-30
Author(s):  
Keyword(s):  
Power Plant ◽  
Wind Power ◽  
Hydraulic System ◽  
Working Fluid ◽  
Wind Power Plant ◽  
Hydraulic Systems ◽  
Hydraulic Motor ◽  
Hydraulic Pump ◽  
Oil Pump ◽  
Selection Of

An algorithm is proposed for calculating a closed volumetric hydraulic pump-hydraulic motor system using the example of the hydraulic system of a wind power plant, based on the calculation of the hydraulic systems of mobile machines. The main characteristics of the system components, the selection of initial data for the calculation, working fluid and diameters of hydraulic lines are analyzed. Keywords: hydraulic system, energy, fluid, oil, pump, motor, renewable energy source, wind power plant, machine. [email protected]

STEAM: A Mobile Hydraulic System With Engine Integration

2013 ◽  
Author(s):  
Milos Vukovic ◽  
Sebastian Sgro ◽  
Hubertus Murrenhoff
Keyword(s):  
Hydraulic System ◽  
High Efficiency ◽  
Combustion Engine ◽  
Low Cost ◽  
Total System ◽  
Hydraulic Systems ◽  
Pressure System ◽  
Operating Modes ◽  
Hydraulic Design ◽  
Displacement Pump

In recent years, research institutions worldwide have developed a number of new mobile hydraulic systems. Despite their improved energy efficiency, these systems have yet to gain market acceptance due to their related increase in component costs and decrease in robustness. At the Institute for Fluid Power Drives and Controls in Aachen, a new system for mobile machines, named STEAM (Steigerung der Energieeffizienz in der Arbeitshydraulik mobiler Arbeitsmaschinen), is being developed using inexpensive off-the-shelf components. The aim is to improve the total system efficiency by considering all the subsystems in the machine. This is done by integrating the internal combustion engine (ICE) into the hydraulic design process. By using a constant pressure system in combination with a low-cost fixed displacement pump the hydraulic system is designed to ensure the ICE experiences a constantly high load in a region of high efficiency, so-called point operation. To decrease the hydraulic losses incurred when supplying the linear actuators with flow, an additional intermediate pressure rail with independent metering edges is used. This enables various energy efficient discrete operating modes, including energy regeneration and recuperation.

scholarly journals Hybrid Control Accommodation forWater-asset Management of Hydraulic Systems Subjected to Large Operating Conditions

2007 ◽  
Vol 2 (3) ◽  
pp. 241
Author(s):  
Eric Duviella ◽  
Pascale Chiron ◽  
Philippe Charbonnaud
Keyword(s):  
Asset Management ◽  
Hydraulic System ◽  
Hybrid Control ◽  
Operating Conditions ◽  
Hydraulic Systems ◽  
Selection Technique ◽  
Operating Modes ◽  
Transfer Delay ◽  
Simulation Results

The Hybrid Control Accommodation (HCA) strategy was proposed to improve the water-asset management of hydraulic systems by resource allocation and setpoint assignment. Hydraulic system dynamics are taken into account during the setpoint assignment step which consists in controlling gates for large operating conditions. For hydraulic systems subjected to strong disturbances, transfer delays are variable, thus different operating modes must be considered. A multimodelling method, associated to a selection technique of transfer delay, allowing for the determination of the number of models, is proposed. The simulation results on the first reach of the Neste canal show the effectiveness of the HCA strategy.

scholarly journals РОЗРАХУНКОВА МОДЕЛЬ ГІДРООБПРИСКУВАЛЬНОЇ УСТАНОВКИ ТУНЕЛЬНОГО ТИПУ

2014 ◽  
pp. 96-101
Author(s):  
О. М. Іванов ◽  
В. М. Арендаренко
Keyword(s):  
High Pressure ◽  
Hydraulic System ◽  
Theoretical Studies ◽  
Hydraulic Parameters ◽  
Computational Studies ◽  
Hydraulic Systems ◽  
Chamber Studies ◽  
Main Components ◽  
The Relationship ◽  
Selection Of

Наведено результати теоретичних досліджень зіскладання розрахункової моделі гідрообприскувальноїустановки тунельного типу, призначеної для обприс-кування під високим тиском рослин у тунельній каме-рі. Дослідження проводились із залученням теоріїгідродинаміки та гідростатики для розрахунку скла-дних трубопроводів і багатокомпонентних гідравліч-них систем. За результатами розрахункових дослі-джень було складено аналітичні рівняння, що визна-чають величини гідравлічних параметрів у вузловихточках і встановлюють взаємозв’язок між основни-ми компонентами гідравлічної установки. The results of theoretical studies on the preparation of the computational model hydro spray tunnel designed for spraying high-pressure plants in the tunnel chamber. Studies were carried out using the theory of hydrodynamic and hydrostatic calculations for complex pipelines and multi-hydraulic systems. To achieve the objectives of the study were divided into components of hydraulic systems, each of which is a more simplified version of a complex pipeline. According to the results of computational studies were compiled analytical equations that determine the magnitude of hydraulic parameters at nodes and establish the relationship between the main components of the hydraulic system, and outlines the framework for the selection of a pressure pump for the amount of required pressure and flow.

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.

Soft Switching Approach to Reducing Transition Losses in an On/Off Hydraulic Valve

2009 ◽  
Author(s):  
Michael B. Rannow ◽  
Perry Y. Li
Keyword(s):  
Hydraulic System ◽  
Check Valve ◽  
Fluid Flows ◽  
Soft Switching ◽  
Total System ◽  
System Efficiency ◽  
Hydraulic Systems ◽  
Controlled Systems ◽  
Flow Through ◽  
Hydraulic Valve

A method for significantly reducing the losses associated with an on/off controlled hydraulic system is proposed. There has been a growing interest in the use of on/off valves to control hydraulic systems as a means of improving system efficiency. While on/off valves are efficient when they are fully open or fully closed, a significant amount of energy can be lost in throttling as the valve transitions between the two states. A soft switching approach is proposed as a method of eliminating the majority of these transition losses. The operating principle of soft switching is that fluid can temporarily flow through a check valve or into a small chamber while valve orifices are partially closed. The fluid can then flow out of the chamber once the valve has fully transitioned. Thus, fluid flows through the valve only when it is in its most efficient fully open state. A model of the system is derived and simulated, with results indicating that the soft switching approach can reduce transition and compressibility losses by 79%, and total system losses by 66%. Design equations are also derived. The soft switching approach has the potential to improve the efficiency of on/off controlled systems and is particularly important as switching frequencies are increased. The soft switching approach will also facilitate the use of slower on/off valves for effective on/off control; in simulation, a valve with soft switching matched the efficiency an on/off valve that was 5 times faster.

Dynamic balance analysis of contamination control for hydraulic systems based on dynamic filtration ratio

2016 ◽  
Vol 68 (1) ◽  
pp. 45-51
Author(s):  
Guangying Ma ◽  
Shurong Ning ◽  
Yunlong Hu ◽  
jun Gao
Keyword(s):  
Hydraulic System ◽  
Dynamic Balance ◽  
Contamination Level ◽  
Hydraulic Systems ◽  
Level Control ◽  
Content Type ◽  
Contamination Control ◽  
Precise Control ◽  
Dynamic Filtration ◽  
The Relationship

Purpose – The aim of this study is to establish a dynamic model of the filtration ratio. For the problem that the measured value of the filtration ratio is far less than the theoretical value in the actual hydraulic filtering system, the paper aims to find the relationship between the filtration ratio and the parameters of the hydraulic systems, such as the contamination level and the dirt-holding quantity of the filter. Design/methodology/approach – The paper opted for the method of experimental analysis and simulation to determine the relationship between the filtration ratio and the parameters of the hydraulic system, and established a dynamic filtration ratio model. Findings – The paper provides a preliminary model of dynamic filtration ratio, and the model shows that the filtration ratio is exponentially related to the contamination level and the dirt-holding quantity. Different filters have different influence coefficients. The filtering capacity for a certain particle size and the contamination level control of the filter for different hydraulic systems can be judged according to the dynamic balance equation of hydraulic systems. Originality/value – The paper is useful in the selection of filters and in the precise control of the contamination level of the hydraulic system.

Optimum Selection of Hydraulic Devices for Water Hammer Control in the Pipeline Systems Using Genetic Algorithm

2003 ◽  
Author(s):  
Bong Seong Jung ◽  
Bryan W. Karney
Keyword(s):  
Genetic Algorithm ◽  
Steady State ◽  
Optimization Problems ◽  
System Optimization ◽  
Water Hammer ◽  
Pipeline System ◽  
Optimal Size ◽  
Protection Strategy ◽  
Hydraulic Devices ◽  
Selection Of

Genetic algorithms have been used to solve many water distribution system optimization problems, but have generally been limited to steady state or quasi-steady state optimization. However, transient events within pipe system are inevitable and the effect of water hammer should not be overlooked. The purpose of this paper is to optimize the selection, sizing and placement of hydraulic devices in a pipeline system considering its transient response. A global optimal solution using genetic algorithm suggests optimal size, location and number of hydraulic devices to cope with water hammer. This study shows that the integration of a genetic algorithm code with a transient simulator can improve both the design and the response of a pipe network. This study also shows that the selection of optimum protection strategy is an integrated problem, involving consideration of loading condition, device and system characteristics, and protection strategy. Simpler transient control systems are often found to outperform more complex ones.

Synchronous Control Characteristics Analysis of Shield Propulsion Hydraulic System Based on Tracking Differentiator and Self-Adaptive Nonlinear PID

2021 ◽  
Author(s):  
Sen Li ◽  
XiaoHua Cao
Keyword(s):  
Pid Control ◽  
Hydraulic System ◽  
Control Method ◽  
Hydraulic Systems ◽  
Fuzzy Pid Control ◽  
Synchronous Control ◽  
Tracking Differentiator ◽  
Characteristics Analysis ◽  
Servo Tracking ◽  
Self Adaptive

Aiming at the low precision problem of multi-cylinder cooperative propulsion control in different regions of shield propulsion hydraulic systems under conditions of large load changes, this paper proposes a tracking differentiator and self-adaptive nonlinear PID (TD-NPID) control method to improve the synchronous control characteristics of shield propulsion hydraulic systems. First, the working principles of shield propulsion hydraulic systems were analyzed, and a mathematical model and TD-NPID controller were developed. Then, a simulation model was developed in AMESim-MATLAB environment, and the synchronous dynamic performances of fuzzy PID control, conventional PID control, and TD-NPID control were compared and analyzed. The results demonstrated that the shield propulsion hydraulic system with TD-NPID control had better servo tracking ability and steady-state performance than the systems with fuzzy or conventional PID control, which verified the feasibility of the application of TD-NPID control for the synchronous control of shield propulsion hydraulic systems.

scholarly journals The Influence of Valve-Pump Weight Ratios on the Dynamic Response of Leaking Valve-Pump Parallel Control Hydraulic Systems

2018 ◽  
Vol 8 (7) ◽  
pp. 1201 ◽  
Author(s):  
Haigang Ding ◽  
Jiyun Zhao ◽  
Gang Cheng ◽  
Steve Wright ◽  
Yufeng Yao
Keyword(s):  
Dynamic Response ◽  
Hydraulic System ◽  
Weight Ratio ◽  
Open Loop ◽  
Hydraulic Systems ◽  
Variable Speed ◽  
Weight Factors ◽  
Wide Range ◽  
Parallel Control ◽  
Valve Control

A new leaking valve-pump parallel control (LVPC) oil hydraulic system is proposed to improve the performance of dynamic response of present variable speed pump control (VSPC) system, which is an oil hydraulic control system with saving energy. In the LVPC, a control valve is operating at leaking status, together with a variable speed pump, to regulate the system flow of hydraulic oil simultaneously. Therefore, the degree of valve control and pump control can be adjusted by regulating the valve-pump weight ratio. The LVPC system design, mathematical model development, system parameter and control performance analysis are carried out systematically followed by an experimental for validation process. Results have shown that after introducing the valve control, the total leakage coefficient increases significantly over a wide range with the operating point and this further increases damping ratios and reduces the velocity stiffness. As the valve-pump weight ratio determines the flow distribution between the valve and the pump and the weight factors of the valve and/or the pump controls determines the response speed of the LVPC system, thus if the weight factors are constrained properly, the LVPC system will eventually have a large synthetic open-loop gain and it will respond faster than the VSPC system. The LVPC will enrich the control schemes of oil hydraulic system and has potential value in application requiring of fast response.

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