scholarly journals Study of Aircraft Wing Flap Hydraulic System Dynamics Under Damages Due to Operating an Aircraft

2008 ◽  
Vol 6 (3) ◽  
pp. 73-88
Author(s):  
Józef Błachnio ◽  
Andrzej Gronczewski
Keyword(s):  
Mathematical Model ◽  
System Dynamics ◽  
Simulation Study ◽  
Hydraulic System ◽  
Hydraulic Systems ◽  
Aircraft Wing ◽  
Wear And Tear

Study of Aircraft Wing Flap Hydraulic System Dynamics Under Damages Due to Operating an Aircraft The paper indicates the main reasons for faulty operation of aeroplane wing flap hydraulic systems. A mathematical model of the wing flap dynamics has been presented, allowing an analysis of a simulation study taking into account damages due to usual wear and tear during operating of a plane.

scholarly journals The study of dynamic processes in the hydraulic system of the roll clamp of a two-cone unwinder rolls pipe-welding unit 159-529

2020 ◽  
Vol 2 (127) ◽  
pp. 25-44
Author(s):  
Igor Mazur ◽  
Dmitry Sheludko ◽  
Mykhailo Petrov
Keyword(s):  
Mathematical Model ◽  
Differential Equations ◽  
Hydraulic System ◽  
High Reliability ◽  
Operating Experience ◽  
Dynamic Loads ◽  
Hydraulic Systems ◽  
Software Environment ◽  
Return Stroke ◽  
Pipe Welding

The work is devoted to the study of dynamic loads arising in the hydraulic system of the clamping mechanism of a roll of a two-cone unwinder of rolls of tubes of a pipe-welding unit 159-529. The operating experience of the two-cone unwinder has shown that one of its drawbacks is the unsatisfactory operation of the roll clamp hydraulic system, in which increased dynamic loads are observed. In the hydraulic system of the roll clamping mechanism, the executive hydraulic cylinder is located at a large distance from the pressure source, therefore, it uses long hydraulic lines. In transient modes of operation of a machine with such a hydraulic system, wave processes arise in it (unsteady fluid motion), which affect the quality of its functioning.Based on the analysis of mathematical models used in the practice of dynamic calculations of real hydraulic systems, it is shown that it is advisable to use a system of partial differential equations converted by a finite-difference method into a system as a mathematical model that takes into account the design and operation of the hydraulic system of the roll clamp mechanism of a two-cone unwinder ordinary differential equations with boundary conditions. This makes it possible to create a dynamic model that allows with high reliability to analyze the behavior of the hydraulic system of the mechanism of the clamping roll of a two-cone unwinder. During the implementation of the proposed mathematical model in the Simulink MATLAB software environment, a study was made of the operating modes of the hydraulic system of the roll clamping mechanism. As a result of the study, it was shown that in the hydraulic system of the roll clamping mechanism of a two-cone unwinder, dynamic loads occur at the end of the return stroke, which significantly exceed the permissible values.In order to reduce dynamic loads, a valve operating procedure with a response time of 0.16 seconds is proposed. This allows you to significantly reduce dynamic loads in the hydraulic system of the roll clamping mechanism by reducing the speed of movement of the hydraulic cylinders at the end of the carriage return stroke.

Simulation Analysis of Rotary Steering Pump-Control Hydraulic System

2013 ◽  
Vol 295-298 ◽  
pp. 1995-2000
Author(s):  
Guang Fu Chen ◽  
Xiao Xian Yao ◽  
Si Bao Li
Keyword(s):  
Mathematical Model ◽  
Comparative Analysis ◽  
Input Signal ◽  
Hydraulic System ◽  
Simulation Analysis ◽  
Harsh Environment ◽  
Hydraulic Systems ◽  
New Form ◽  
The Mathematical Model ◽  
Valve Control

The traditional valve control hydraulic systems have serious challenges in the harsh environment underground. The mathematical model of this new form of "motor - quantitative pump" controll system was established and simulated by using AMESIM software in this paper. According to the results of comparative analysis of the orifice parameters and the way to input signal, related parameters was determined, which can meet the characteristics of the system.

scholarly journals ALGORITHM OF CONTROLLING AN ADAPTIVE HYDRAULIC CIRCUIT FOR MOBILE MACHINES

2021 ◽  
Vol 13 (3) ◽  
pp. 79-86
Author(s):  
Leonid Kozlov ◽  
◽  
Yurii Buriennikov ◽  
Oana Rusu ◽  
Volodymyr Pyliavets ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Hydraulic System ◽  
Hydraulic Systems ◽  
Hydraulic Circuit ◽  
Nonlinear Mathematical Model ◽  
Rosenbrock Method ◽  
Soil Hardness ◽  
Loose Soil ◽  
Feed Value ◽  
The Mathematical Model

Hydraulic systems based on adjustable pumps, proportional electrohydraulic equipment and controllers are used in mobile machines. The authors propose a new scheme of the hydraulic system for mobile machines, which provides the auger drilling operation. A number of studies have shown that a certain ratio should be maintained between the frequency of auger rotation and its feed during operation, where the productivity of soil disruption should not exceed the productivity of transporting loose soil from the drilling zone. Ensuring the required ratio between the speed of the auger rotation and its feed is implemented by a controller that works according to a certain algorithm. A nonlinear mathematical model of the hydraulic system was developed to create the algorithm for controller operation and setting. The equations of the mathematical model are solved in the MATLAB-Simulink environment by the Rosenbrock method. As a result of solving the equations for the mathematical model, the dependences of variables describing the state of the hydraulic system on time are obtained. The values of the controller settings are determined at which the hydraulic system works steadily, the error of flow rate stabilization, the time for pressure adjustment and readjustment does not exceed the allowable values. The algorithm for controlling the auger feed value is formed. This algorithm provides the necessary ratio between the auger feed and speed, as well as reducing the feed rate in the case of soil hardness increases. This creates the conditions for uninterrupted pit drilling at full depth and protection of the hydraulic system from overload.

scholarly journals Transient Phenomena Generated in Emptying Operations in Large-Scale Hydraulic Pipelines

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2313
Author(s):  
Guillermo Romero ◽  
Vicente S. Fuertes-Miquel ◽  
Óscar E. Coronado-Hernández ◽  
Román Ponz-Carcelén ◽  
Francisco Biel-Sanchis
Keyword(s):  
Mathematical Model ◽  
Hydraulic System ◽  
Large Scale ◽  
Hydraulic Systems ◽  
Transient Phenomena ◽  
Pressure Drops ◽  
Pipeline Route ◽  
Air Pockets ◽  
Pressure Changes ◽  
The Mathematical Model

Air pockets generated during emptying operations in pressurized hydraulic systems cause significant pressure drops inside pipes. To avoid these sudden pressure changes, one of the most widely used methods involves the installation of air valves along the pipeline route. These elements allow air exchange between the exterior and the interior of the pipe, which alleviates the pressure drops produced and thus prevents possible breaks or failures in the structure of the installation. This study uses a mathematical model previously validated by the authors in smaller installations to simulate all hydraulic variables involved in emptying processes over time. The purpose of these simulations is the validation of the mathematical model in real large-scale installations, and to do this, the results obtained with the mathematical model are compared with actual measurements made by the partner company. The hydraulic system selected for the study is a pipeline with a nominal diameter of 400 mm and a total length of 1020 m. The results obtained from the mathematical model show great similarity with the experimental measurements, thus validating the model for emptying large pipes.

scholarly journals Simulation of parallel capacitance influence on the hydraulic system dynamics

2019 ◽  
Vol 213 ◽  
pp. 02016
Author(s):  
Dýrr Filip ◽  
Hružík Lumír ◽  
Bureček Adam ◽  
Brzezina Petr
Keyword(s):  
Mathematical Model ◽  
System Dynamics ◽  
Mathematical Simulation ◽  
Experimental Measurement ◽  
Hydraulic System ◽  
Stationary Flow ◽  
Pressure Response ◽  
Hydraulic Circuit

This paper covers with experimental measurement and mathematical simulation of parallel capacitance influence on pressure response for non-stationary flow. The hydraulic circuit for measuring required quantities, which are necessary to determine of parallel capacitance influence on the hydraulic system dynamics. A part of hydraulic system is a long pipe, in which the parallel capacitance created by hydraulic hose is connected. A non-stationary flow is caused by fast closing of the seat valve, which is situated at the end of long pipe. Mathematical model is realized and verified in Matlab SimScape Fluids software for this hydraulic system.

THE DEVELOPMENT OF THE MATHEMATICAL MODEL OF PREDICTING THE INDICATORS OF ACCREDITATION OF TECHNICAL UNIVERSITIES IN THE RUSSIAN FEDERATION

2017 ◽  
pp. 27-38
Author(s):  
Olga Mikhaylovna Tikhonova ◽  
Alexander Fedorovich Rezchikov ◽  
Vladimir Andreevich Ivashchenko ◽  
Vadim Alekseevich Kushnikov
Keyword(s):  
Mathematical Model ◽  
System Dynamics ◽  
Regression Model ◽  
Oriented Graph ◽  
Real Data ◽  
Educational Process ◽  
Proposed Model ◽  
Linear Differential ◽  
The University ◽  
The Mathematical Model

The paper presents the system of predicting the indicators of accreditation of technical universities based on J. Forrester mechanism of system dynamics. According to analysis of cause-and-effect relationships between selected variables of the system (indicators of accreditation of the university) there was built the oriented graph. The complex of mathematical models developed to control the quality of training engineers in Russian higher educational institutions is based on this graph. The article presents an algorithm for constructing a model using one of the simulated variables as an example. The model is a system of non-linear differential equations, the modelling characteristics of the educational process being determined according to the solution of this system. The proposed algorithm for calculating these indicators is based on the system dynamics model and the regression model. The mathematical model is constructed on the basis of the model of system dynamics, which is further tested for compliance with real data using the regression model. The regression model is built on the available statistical data accumulated during the period of the university's work. The proposed approach is aimed at solving complex problems of managing the educational process in universities. The structure of the proposed model repeats the structure of cause-effect relationships in the system, and also provides the person responsible for managing quality control with the ability to quickly and adequately assess the performance of the system.

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.

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]

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