The Inertia Force of the Vanes in the Hydraulic Vane Pump with Advanced Hypertrochoid Curve in the Inner Surface of its Stator

2013 ◽  
Vol 325-326 ◽  
pp. 1440-1444 ◽  
Author(s):  
Mojtaba Ebrahimi ◽  
Seyed Ali Jazayeri
Keyword(s):  
Inertial Force ◽  
Inertia Force ◽  
Vane Pump ◽  
Regular Motion ◽  
Sliding Motion ◽  
Radial Movement ◽  
Inner Surface

The possibility of application of the advanced hypertrochoid curve in the inner surface of the stator of fixed displacement hydraulic vane pump, theoretically was studied in the last our work. By considering the properties of this curve, sealing action between pressure and suction sides of the pump can be improved. One of the important characteristics of a new profile must be improving of the inertial reaction of the vanes in each position where these vanes have a radial movement because it causes a smooth sliding motion of the vanes, and hence, a higher performance of the pump while attaining a longer life of it. Then at this paper, the effect of the inertial force of the vanes on the performance of the pump with this curve will be studied. The regular motion of the vanes on the inner surface of the stator with smooth profile suppresses the lateral reactional force applied to the vanes and results to diminish local wear of the vanes tip and noise.

A Study of the Effect of the Inertia Force of the Vanes on the Performance of the Hydraulic Vane Pump with Hypertrochoid Curve in the Inner Surface of its Stator

2012 ◽  
Vol 463-464 ◽  
pp. 297-300
Author(s):  
M. Ebrahimi ◽  
S.A. Jazayeri
Keyword(s):  
Inertia Force ◽  
Vane Pump ◽  
Sliding Motion ◽  
Radial Movement ◽  
Inner Surface ◽  
Vibration Noise ◽  
Hydraulic Balance ◽  
Vane Tip

Performance of a fixed displacement hydraulic balance vane pump, theoretically and practically was studied by application of the hypertrochoid curve in the inner surface of its stator. In addition to improving a sealing action between pressure and suction sides of the pump, one of the important characteristics of the hypertrochoid profile is improving of the inertial reaction of the vanes in each position where these vanes have a radial movement. Then it causes a smooth sliding motion of the vanes, and hence, a higher performance of the pump while attaining a longer life of it because of decreasing vane- tip and inner surface of stator wear and decreasing of vibration, noise and high stresses.

A Theoretical Study of the Internal Forces in a Hydraulic Vane Pump with Hypertrochoid Curve in the Inner Surface of its Stator

2012 ◽  
Vol 463-464 ◽  
pp. 301-304 ◽  
Author(s):  
M. Ebrahimi ◽  
S.A. Jazayeri
Keyword(s):  
Inertia Force ◽  
Fluid Viscosity ◽  
Vane Pump ◽  
Pump Design ◽  
Inner Surface ◽  
Dynamics And Control ◽  
Internal Forces ◽  
Line Pressure ◽  
And Control ◽  
Selection Of

In the latest our works, Performance of a fixed displacement- hydraulic balance vane pump, theoretically and practically was studied by application of the basic hypertrochoid curve in the inner surface of its stator. Also the effect of the inertia force of the vanes on the performance of the pump with this curve was studied. This study presents a theoretical analysis of the internal pressure distribution in the pump, and of the resulting forces and torques applied to its components. This analysis is essential to the study of the pump dynamics and control, the pump design, and selection of the pump bearings. These forces are shown to be a function of the line pressure, the shaft rotational speed, the fluid bulk modulus, the fluid viscosity, and the design geometry. These forces are composed of two components: a continuous component due to the exposure of chambers to the line port, and an intermittent component due to a hydraulic lock phenomenon.

scholarly journals Inertial property of oscillatory flow for pulse injection in porous media

2021 ◽  
pp. 014459872199978
Author(s):  
Bingyu Ji ◽  
Yingfu He ◽  
Yongqiang Tang ◽  
Shu Yang
Keyword(s):  
Capillary Number ◽  
Pressure Pulse ◽  
Two Phase Flow ◽  
Inertial Force ◽  
Inertia Force ◽  
Phase Flow ◽  
High Permeability ◽  
Two Phase ◽  
Apparent Permeability ◽  
Inertial Property

The low-frequency pulse wave makes the velocity of the fluid in the reservoir fluctuate dramatically, which results in a remarkable inertia force. The Darcy’s law was inapplicable to the pulse flow with strong effect of inertial force. In this paper, the non-Darcy flow equation and the calculation method of capillary number of pressure pulse displacement are established. The pressure pulse experiments of single-phase and two- phase flow are carried out. The results show that the periodic change of velocity can decrease the seepage resistance and enhance apparent permeability by generating the inertial force. The higher the pulse frequency improves the apparent permeability by enhancing influence of inertial force. The increase of apparent permeability of high permeability core is larger than that of low permeability core, which indicates that inertial force is more prominent in high permeability reservoir. For the water-oil two-phase flow, inertia force makes the relative permeability curve move towards right, and the equal permeability point becomes higher. In other words, with the increase of capillary number, part of residual oil is activated, and the displacement efficiency is improved.

scholarly journals Structure Analysis and Optimization for Compacting System of Asphalt Paver

2015 ◽  
Vol 9 (1) ◽  
pp. 86-91
Author(s):  
Sun Jian
Keyword(s):  
Mass Distribution ◽  
Asphalt Concrete ◽  
Impact Force ◽  
Inertial Force ◽  
Theoretical Method ◽  
Force Balance ◽  
Simplified Model ◽  
Inertia Force ◽  
The Stability

Compound motion of double-tamper mechanism causes an impact force on the frame of flatiron-box, which affects the quality of the load when the asphalt paver is running. Different from the previous simplified model, in this paper, the double-tamper mechanism with two parallel slider-cranks is considered. According to the analysis of the structure and principle of the mechanism, and considering the size and mass distribution of each component, the inertia force balance optimization for the double vibrating mechanism is calculated. According to the results of optimization, the vibration experiments were carried out on real screed. The experimental results show that, the harmful inertial force produced by the dual tamping mechanism has been significantly reduced, and the stability of vibration can be effectively improved when screed is paving. The research could provide reliable theoretical method and basis for design, manufacturing and use of asphalt concrete paver.

Analysis of the Effect of External Factors to the Propulsion by Inertial Centrifugal Force of Rotating Mechanism

2014 ◽  
Vol 487 ◽  
pp. 343-347 ◽  
Author(s):  
Qing Ming Wang ◽  
Jia Chen Ju
Keyword(s):  
Inertial Force ◽  
Friction Condition ◽  
External Factors ◽  
Inertia Force ◽  
Support Surface ◽  
Supporting Surface ◽  
Directional Movement ◽  
Directional Motion ◽  
Rotary Speed ◽  
Internal Inertia

The idea of inertial propulsion using rotating parts is always attractive, but great controversy also exists. Some researchers even completely negate this idea in principle, they think it would never be possible to create directional movement by the inertial force. Theory and experimental results show that, in certain conditions, directional movement can be realized by the internal inertia force of the device. In this paper, the influence of the friction condition between the propulsion devices which using rotating eccentric mass to generate inertia force and the external supporting surface on the effect of propulsion has been analyzed. The results show that, when there is friction between the device and the supporting surface, the rotary of eccentric mass in the device will allow the device to produce motion in a given direction; if the parameters of propulsion device (eccentric mass and eccentricity) and the rotary speed of the eccentric mass are given, the friction condition between the device and the support surface will affect the characteristics of directional motion.

Binding Force Analysis of Multiple Pairs of Bars Space RCCR Mechanism without Inertia Force

2013 ◽  
Vol 397-400 ◽  
pp. 457-460
Author(s):  
Sen Zhuang ◽  
Chao Cui ◽  
Bo Han ◽  
Kai Ouyang
Keyword(s):  
Theoretical Analysis ◽  
Rigid Body ◽  
Multibody Dynamics ◽  
Body Condition ◽  
Tangential Force ◽  
Inertial Force ◽  
Inertia Force ◽  
Force Analysis ◽  
Simulation Data ◽  
Binding Force

In close to the rigid body condition,to solve the binding force of multiple pairs of bars space RCCR mechanism,first, starting from solving main binding force of three-pair bars space RCCR mechanism by the theoretical analysis, to have obtained the change law of the main binding force without the inertial force (extremely low speed) by using the computational multibody dynamics software ’COSMOSMotion’ and then summed up the equivalent tangential force through the investigation of the simulation data. Finally the concept of equivalent tangential binding force was expanded to 4, 5, 6 pairs of bars space RCCR mechanism.

scholarly journals Seismic damage mechanism of slope and lining in the mountain tunnel portal section

2020 ◽  
Vol 165 ◽  
pp. 04073
Author(s):  
Hua Xu ◽  
Runfang Sun ◽  
Jingsong Xu ◽  
Yinfei Tang ◽  
Peng Zhang
Keyword(s):  
Tensile Stress ◽  
Inertial Force ◽  
Axial Direction ◽  
Damage Mechanism ◽  
Seismic Damage ◽  
Inertia Force ◽  
Seismic Load ◽  
2008 Wenchuan Earthquake ◽  
Tunnel Portal ◽  
Mountain Tunnel

A series of numerical simulations were conducted to study the seismic response in the mountain tunnel portal section. The seismic damage mechanism, including slope cracking and landslide, rockfalls and collapse, and lining cracking were analyzed based on the seismic damage characteristics of the Longxi tunnel during the 2008 Wenchuan earthquake in China. The results show that slope cracking due to the huge horizontal seismic inertial force which exceeds the strength of slope; landslide is caused by the connected cracks where the oblique component of horizontal seismic inertia force exceeds the shear strength of slope; rockfalls and collapse are caused by the cumulative tensile stress in loose soil and rock which exceed the strength of slope; the transverse lining cracks due to the alternate tensile and compressive action of the seismic load along the axial direction, which makes the lining tensile strain accumulates and exceeds the concrete ultimate strength. As for the longitudinal lining cracking, the transverse seismic load makes the bending moment direction in lining alternates, leading to the strength reduction of concrete. Moreover, the circumferential penetrating rupture zone is caused by the large shear force resulting from the slope sliding, which leads to the stress concentration at vault and when the tensile stress exceeds the concrete tensile strength, the vault begins to crack, and then the cracks extend from the arch shoulder to foot.

Study on the Seismic Response of Cable Tray Considering Sliding Motion of Cable

2014 ◽  
Author(s):  
Tomohiro Ito ◽  
Yasuhiko Azuma ◽  
Atsuhiko Shintani ◽  
Chihiro Nakagawa
Keyword(s):  
Power Plants ◽  
Structural Integrity ◽  
Thermal Power ◽  
Vertical Direction ◽  
Inertia Force ◽  
System Response ◽  
Seismic Responses ◽  
Sliding Motion ◽  
Highly Nonlinear ◽  
Supporting Structures

In various industrial plants such as thermal power plants, nuclear power plants, and chemical plants, many cable trays are generally used to support cables for control signals. Cable trays are very long, and thus are supported from ceilings or walls by many supporting structures. When the cable trays are subjected to strong seismic excitations, the trays or the supporting structures vibrate with large amplitudes. In the worst cases, they can collapse, and plants can lose control of systems, which can lead to severe accidents. Therefore, it is very important to maintain the structural integrity of cable trays during seismic events including recent severe earthquakes such as the East Japan Earthquake in 2011. Cable trays are generally made of thin steel plates with sides folded in the vertical direction, and with cables simply placed on the tray. Thus, cables can slide when the inertia force on the cables exceeds the friction force between the tray and cables. The mass of the cables is relatively large compared to that of a tray, thus the natural frequency of the tray will change significantly due to the cable sliding motion. Consequently, seismic responses of cable tray will also depend on the sliding motion of cables. Therefore, cable trays are seen as highly nonlinear structural systems. In this study, seismic responses of cable trays are investigated analytically considering cable sliding motions. A cable tray is modeled by a two-degree-of-freedom system. Response acceleration, and the displacements of the tray and the cable are evaluated for both sinusoidal and seismic inputs by varying the cable mass or friction coefficient between the tray and cables. It is confirmed that the sliding motion of the cable has a very large influences on the seismic responses of the cable-tray system.

scholarly journals Research on Theoretical Modeling and Parameter Sensitivity of a Single-Rod Double-Cylinder and Double-Coil Magnetorheological Damper

2020 ◽  
Vol 2020 ◽  
pp. 1-20
Author(s):  
Suojun Hou ◽  
Gang Liu
Keyword(s):  
Inertial Force ◽  
Mr Damper ◽  
Bond Graph ◽  
Inertia Force ◽  
Force Model ◽  
Damping Force ◽  
Mr Fluid ◽  
Force Velocity ◽  
Force Displacement ◽  
Bond Graph Theory

For the single-rod double-cylinder and double-coil magnetorheological (MR) damper studied in this paper, the damping force model of the damper is established by adopting multidisciplinary domain modeling method bond graph theory. Firstly, combined with the structure of the MR damper, the bond graph model of the MR damper was established, the damping force model of the damper was derived through the bond graph theory, and the influence factors, such as the displacement, velocity, and acceleration of the damper were considered in the model. Based on the simulation of force-displacement and force-velocity characteristics of the damping force carried out by the damper theoretical model under different currents and velocities as well as the comparison with the damper bench test results, it was found that the force-displacement and force-velocity characteristic experiment curves of the damper agreed well with the simulation results. Under different working conditions, the maximum error of damping force of the MR damper was 7.2%. The damping force model of the MR damper studied in this paper was compared with that of the damper without considering the inertia force of MR fluid, and the influence of the inertia force of MR fluid on the damping force of the MR damper was analyzed. The results show that when the frequency of the damper is large, the inertial force of MR fluid has an important influence on the damping force; therefore, considering the inertial force of MR fluid in the model can greatly improve the accuracy of the model. The influence degree of key parameters on the damping force of the MR damper was studied through the theoretical model; such key parameters ranging from large to small were the channel clearance, energizing current, piston diameter, motion velocity, channel length, zero-field viscosity of MR fluid, and nitrogen pressure. This provides a basis for the adjustment of the damping force of the MR damper.

Nonlinear Inertia Forces on Slender Cylindrical Members

1984 ◽  
Vol 106 (2) ◽  
pp. 222-225
Author(s):  
A. N. Williams
Keyword(s):  
Diffraction Problem ◽  
Inertial Force ◽  
Wave Force ◽  
Inertia Force ◽  
Linear Potential ◽  
Incident Wavelength ◽  
Mass Coefficient ◽  
Linear Potential Theory ◽  
Nonlinear Wave Force ◽  
Fifth Order

An expression for the nonlinear wave force on a vertical, circular cylindrical member whose diameter is small compared to the incident wavelength is derived from an exact solution to the second-order diffraction problem. A comparison is then made with the inertial force estimates obtained using Stokes’ second and fifth-order wave theories in Morison’s equation with a mass coefficient derived from linear potential theory, as is currently recommended in the offshore design codes. Results indicate that in water depths of the order of 1/16 of a wavelength, nonlinear free-surface effects contribute significantly to the total inertia force on a slender cylindrical member.

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