scholarly journals Methodology for substantiating the design parameters of a single-tube hydropneumatic shock absorber

2020 ◽  
Vol 17 (4) ◽  
pp. 166-173
Author(s):  
A. M. Voytko ◽  
Keyword(s):  
Comparative Analysis ◽  
Energy Intensity ◽  
Shock Absorber ◽  
Design Parameters ◽  
Working Fluid ◽  
Hydraulic Shock ◽  
Single Tube ◽  
Operating Modes ◽  
Shock Absorbers ◽  
Selection Of

The article describes the developed methodology for calculating the parameters of a single-tube hydropneumatic shock absorber. The calculation procedure is presented including calculating the volume of the gas filling cavity, calculating the parameters of the gas and the working fluid, determining the energy intensity of the shock absorber, checking the possibility of cavitation in the operating modes, as well as calculating the strength of the shock absorber parts.. A comparative analysis results of the calculated characteristics and the experimental characteristics of the hydropneumatic shock absorber are presented, the absorber having been produced according to the obtained design parameters. Based on the analysis, recommendations are given to increase the running smoothness of the car by replacing the standard hydraulic shock absorbers with hydropneumatic ones, taking into account the selection of the throughput of the discharge valves.

The Effects of Fluid and Mechanical Compliance on the Performance of Hydraulic Shock Absorbers

1974 ◽  
Vol 96 (1) ◽  
pp. 101-106 ◽  
Author(s):  
R. W. Mayne
Keyword(s):  
Differential Equations ◽  
Shock Absorber ◽  
Rigid Wall ◽  
Hydraulic Shock ◽  
Orifice Area ◽  
Shock Absorbers ◽  
Constant Area ◽  
Mechanical Compliance ◽  
Hydraulic Shock Absorber ◽  
The Ideal

Dimensionless differential equations are developed which model a hydraulic shock absorber. These equations are solved numerically to determine quantitatively the effects of fluid compressibility and series and parallel springs on the shock absorber operation. Both variable and constant orifice area are considered for a system protecting a mass during impact against a rigid wall. The results show that a finely tuned variable area shock absorber is degraded by the considered forms of compliance. Performance of the constant area shock absorber can be improved by including compliance and, with an appropriate parallel spring, the ideal flat deceleration profile can be obtained without variable orifice area.

scholarly journals TURBULIZATION METHOD OF FORMATION OF HIGHLY DISPERSED DROPLETS

2020 ◽  
Vol 2020 (1) ◽  
pp. 28-33
Author(s):  
Kh Irisov ◽  
◽  
I Ashirbekov ◽  
A Kartoshkin ◽  
A Abdazimov
Keyword(s):  
Physical Properties ◽  
Design Parameters ◽  
Working Fluid ◽  
Theoretical Studies ◽  
Traditional Methods ◽  
Operating Modes ◽  
Highly Dispersed ◽  
Object Of Study ◽  
Fluid Design

The article critically analyzes traditional methods of forming drops of defoliants and liquid chemicals. As an object of study, a sprayer with a perforated turbulator was selected, which ensures the formation of fine droplets on a short spraying torch. The degree of crushing of the working fluid, design parameters and operating modes of the proposed sprayer are investigated. Based on theoretical studies, analytical dependencies that reveal the physical properties of the sprayed liquid are analyzed, a description of the device and the principle of operation of the sprayer equipped with a perforated turbulator is given. The above analytical dependencies allowed more purposefully improving the design of the proposed atomizer.

Dynamic Modeling and Fluid-Structure Interactive Analysis of an Innovative Self-Tuning Shock Absorber for the Prosthesis Knee Joint

2010 ◽  
Author(s):  
Yen-Chieh Mao ◽  
Wei-Chih Chang
Keyword(s):  
Knee Joint ◽  
Shock Absorber ◽  
Knee Prosthesis ◽  
Element Model ◽  
Heel Strike ◽  
Design Parameters ◽  
Fluid Structure ◽  
Shock Absorbers ◽  
Damper Design ◽  
The Impact

The above-knee prosthesis, as a supplement of the lost biological leg, is supposed to provide equivalent or enhanced shock absorption capability and reduce the shock waves on the amputee body when walking and running. Prosthesis knee joint with a shock absorber is a feasible solution that efficiently absorbs the impact loads during each heel-strike. Conventional shock absorbers consist of springs and dampers with constant coefficients produce excessive rigid reactions when encountering impact forces, while unreasonable weak responses for gentle loads. This study proposes an innovative viscous damper design for the prosthesis knee joint which automatically and smoothly tunes the damping coefficient without any electronic components according to the input force velocities. High order differential system of the shock absorber is constructed and simulates the system dynamics during cyclic loads. The fluid-structure interactive finite element model for key components in the absorber is established in this study. Design parameters of the damper system under certain absorbing performance requirements are determined in this paper.

Comparisons Between Dynamic Characteristics of Pneumatic, Magnetorheological, and Hydraulic Shock Absorbers

2012 ◽  
Author(s):  
A. M. Salem ◽  
S. Olutunde Oyadiji
Keyword(s):  
Dynamic Characteristics ◽  
Shock Absorber ◽  
Testing Machine ◽  
Mr Damper ◽  
Nonlinear Behaviour ◽  
Hydraulic Shock ◽  
Shock Absorbers ◽  
Wide Range ◽  
Force Velocity ◽  
Force Displacement

The dynamic performance of automotive vehicles is influenced by the suspension system design. Suspensions owing damping elements with a wide range of non-linear behaviour can provide higher mobility and better ride comfort performances. Pneumatic suspensions due to their inherent nonlinear behaviour can provide high mobility performance while suspensions with MR dampers can provide this nonlinearity through the controllable damping force produced by the control of the MR fluid. The pneumatic and MR suspension models are usually developed from experimental force-displacement and force-velocity characteristics. The purpose of this paper is to measure and compare the dynamic characteristics of pneumatic, magnetorheological, and hydraulic shock absorbers. The study is carried out through measuring the characteristics of the different types of dampers at different frequencies and amplitudes using an Electro-Servo Hydraulic (ESH) testing machine. The shock absorber is subjected to sinusoidal excitation of frequency varying from 0 to 10 Hz, and amplitude varying from 0 to 10 mm. In the case of the MR damper, the tests are also done at different current levels of between 0 and 2 amp. The input displacement and acceleration to the shock absorber were measured using an LVDT (Linear Voltage Displacement Transducer) and an accelerometer, respectively while the input velocity was derived from the measured displacement and acceleration. This dual identification of the input velocity was done in order to ensure accurate representation of the velocity. The output force response of the shock absorber was measured by means of a force transducer. The force-displacement and force-velocity characteristics of each shock absorber were subsequently derived from the measured data. The results show the tunability of the MR damper characteristics in comparison to those of the pneumatic and hydraulic dampers.

Damping force characteristics of electrorheological shock absorbers with different electrode designs

2010 ◽  
Vol 224 (2) ◽  
pp. 293-304 ◽  
Author(s):  
Y-M Han ◽  
M-S Seong ◽  
S-B Choi ◽  
N M Wereley
Keyword(s):  
Shock Absorber ◽  
Equations Of Motion ◽  
Design Parameters ◽  
Damping Force ◽  
Passenger Vehicles ◽  
Shock Absorbers ◽  
Car Suspension ◽  
Field Dependent ◽  
The Time Domain ◽  
Er Fluid

This article presents the effect of electrode design parameters on the damping force of an electrorheological (ER) shock absorber for passenger vehicles. As a first step, an ER fluid is synthesized by dispersing arabic gum particles into non-conducting oil, and its field-dependent Bingham characteristics are experimentally evaluated. The Bingham model of the ER fluid is then formulated and incorporated with the governing equations of motion of the ER shock absorber. Subsequently, several ER shock absorbers are designed and manufactured with various electrode designs, which have three different electrode gaps, lengths, and materials, respectively. The field-dependent damping force of the manufactured shock absorbers is demonstrated in the time domain and compared with simulation results. In addition, the vibration control performance of a quarter-car suspension system is presented and compared with different electrode gaps and lengths.

Analysis of vibrations for a vibrating jaw crusher when interacting with material

2021 ◽  
pp. 26-31
Author(s):  
A. E. Shokhin ◽  
G. Ya. Panovko ◽  
I. P. Lyan
Keyword(s):  
Vibration Mode ◽  
Excitation Frequency ◽  
Design Parameters ◽  
Operating Modes ◽  
Jaw Crusher ◽  
Stable Periodic ◽  
The Impact ◽  
Excitation Conditions ◽  
Main Operating ◽  
Selection Of

A model of a vibrating jaw crusher (VJC) with self-synchronizing unbalanced vibration exciters is considered with account of the impacts between the jaws and the material being processed. Numerical modeling is used to establish the influence of the initial gap between the jaws and the material and of the velocity recovery factor upon impact on the synchronization of vibration exciters rotation and jaw vibrations, on the excitation frequency ranges of stable periodic vibroimpact regimes, and on the impact velocities between the jaws. The analysis results indicate that a change in the conditions of contact between the jaws and the material being processed leads to a change in the frequency ranges of the stable antiphase synchronization of vibration exciters rotation, as well as in the excitation frequency ranges of steady single-period vibroimpact regimes for the motion of the system, considered as the main operating modes of the VJC. The impact-like nature of the interaction between the jaws and the material being processed suggests the possible multimodality of the system, which explains some of the effects observed in practice and manifested in changes in the periodicity of the vibroimpact regime and in the vibration mode of the jaws at a constant excitation frequency. Therefore, the vibroimpact-based model proposed for the VJC and its dynamics analysis results may be used to design and improve vibrating jaw crushers with the selection of reasonable design parameters and the most effective vibration excitation conditions. The work was carried out with the financial support of the RFBR, project No. 18-08-01491_a.

scholarly journals Development of Pneumatic Shock Absorber by Variable Damping

2019 ◽  
Vol 8 (6) ◽  
pp. 1355-1360
Keyword(s):  
Shock Absorber ◽  
Low Cost ◽  
Advanced Technology ◽  
Hydraulic Shock ◽  
Damping Properties ◽  
The Road ◽  
Shock Absorbers ◽  
Variable Damping ◽  
Cost Efficient ◽  
Pneumatic Shock

In commercial models and premium vehicles the damping is varied by sensing the road conditions, driver’s action etc. using ECU’s and damping properties are varied every second. This advanced technology is very costly and complicated for middle class consumers who also need some comfort with low cost. The main issue here is to vary the damping of hydraulic shock absorbers according to the shock to which it is subjected. Thus by sensing the speed of the shock absorber and changing the vibration absorbing capacity of the damper with respect to it will surely be useful. In this project we used a spring valve to sense the speed of the Shock absorber and controlling the valve which is fitted inside the damper. By Variable damping pneumatic shock absorber we can get enough comfort with a simple and cost efficient setup.

Application of the Signal Change Tracking Algorithm in the Hydraulic Shock Absorber Monitoring System

Vestnik MEI ◽  
2021 ◽  
pp. 132-136
Author(s):  
Andrey A. Shilov ◽  
◽  
Aleksey N. Chernyaev ◽  
Keyword(s):  
Monitoring System ◽  
Shock Absorber ◽  
Statistical Processing ◽  
Linear Displacement ◽  
Residual Lifetime ◽  
Hydraulic Shock ◽  
Reactor Plant ◽  
Shock Absorbers ◽  
Displacement Sensors ◽  
Hydraulic Shock Absorber

During nuclear power plant (NPP) operation, the reactor plant main equipment can show displacements when subjected to the effect of various external and internal loads. These displacements are mainly caused by thermal expansion of the metal and seismic loads. To cope with these phenomena, the reactor plant components that are most susceptible to these types of loads are fastened with hydraulic shock absorbers (HSAs) to limit their displacements under the effect of seismic or accident dynamic loads, as well as to ensure thermal displacements in increasing or decreasing the power unit output. For monitoring the HSA operation and indirectly monitoring the displacements of the reactor plant equipment items fastened with hydraulic shock absorbers, the dedicated hydraulic shock absorber monitoring system (HSAMS) is used, which is equipped with linear displacement sensors installed directly on the HSAs. If the displacements go beyond the predetermined limits, the HSAMs algorithms produce an appropriate alarm. The information from the HSAMS is also used by the automated residual lifetime monitoring system (ARLMS) to calculate the steam generator connection pipe displacement criteria parameters. However, during the operation of a number of NPP power units, a problem associated with numerous failures of the HSAMS linear displacement sensors has been faced. These failures manifested themselves in that the sensor signals went beyond the valid range or frozen under the effect of external influencing factors. As a result, the HSAMS and ARLMS operation was complicated by a large number of unreliable measurements and the functions of these systems were not performed in a proper way. To solve this problem, it has been proposed to use an algorithm for tracking signal changes, which can improve the credibility of HSAMS indications by determining unreliable data in the online mode and by performing statistical processing of the already available array of indications.

scholarly journals The influence of temperature on the damping characteristic of hydraulic shock absorbers

2021 ◽  
Vol 23 (2) ◽  
pp. 346-351
Author(s):  
Zdzisław Hryciów ◽  
Piotr Rybak ◽  
Roman Gieleta
Keyword(s):  
Shock Absorber ◽  
Rate Of Change ◽  
Operating Conditions ◽  
Temperate Climate ◽  
Hydraulic Shock ◽  
Influence Of Temperature ◽  
Shock Absorbers ◽  
Influence Of Temperature On ◽  
Energy Dissipated ◽  
Increasing Temperature

This paper presents the results of bench-tests and calculations assessing the influence of temperature on the performance of a two-pipe hydraulic shock absorber. The shock absorber prepared for the tests was cooled with dry ice to a temperature corresponding to that associated with the average winter conditions in a temperate climate. The temperature range of the shock absorber during testing was ensured via equipping it with a thermocouple and monitoring it with a thermal imaging camera. During testing, the shock absorber was subjected to kinematic forces of a selected frequency with two different, fixed displacement amplitudes. The results of the tests showed a direct correlation between the decrease of component resistance at lower temperatures. The rate of change in resistance was higher at lower temperatures. It was also found that the energy dissipated in one shock cycle decreased linearly with an increasing temperature. Finally, a method for determining the ideal use temperature of the shock absorber for the assumed operating conditions was also presented.

Sign in / Sign up

Export Citation Format

Share Document