scholarly journals Pressure Distribution and Bubble Formation Induced by Longitudinal Vibration of a Flexible Liquid-Filled Cylinder

1967 ◽  
Vol 89 (4) ◽  
pp. 737-747 ◽  
Author(s):  
R. J. Schoenhals ◽  
T. J. Overcamp
Keyword(s):  
Pressure Distribution ◽  
Longitudinal Vibration ◽  
Bubble Formation ◽  
Experimental Results ◽  
Experimental Measurements ◽  
Visual Observations

Analytical and experimental results are presented for a flexible liquid-filled cylinder subjected to forced longitudinal vibration. Analytical predictions are correlated with experimental measurements of pressure amplitudes and threshold acceleration levels required to produce bubble formation, as well as visual observations of the regions in which formations occur.

scholarly journals Numerical and experimental study of the dynamic factor of the dynamic load on the urban railway

2020 ◽  
Vol 29 (1) ◽  
pp. 195-202
Author(s):  
Tran Anh Dung ◽  
Mai Van Tham ◽  
Do Xuan Quy ◽  
Tran The Truyen ◽  
Pham Van Ky ◽  
...  
Keyword(s):  
Experimental Study ◽  
Dynamic Load ◽  
Dynamic Measurement ◽  
Experimental Results ◽  
Load Factor ◽  
Dynamic Factor ◽  
Experimental Measurements ◽  
Train Speed ◽  
Dynamic Load Factor

AbstractThis paper presents simulation calculations and experimental measurements to determine the dynamic load factor (DLF) of train on the urban railway in Vietnam. Simulation calculations are performed by SIMPACK software. Dynamic measurement experiments were conducted on Cat Linh – Ha Dong line. The simulation and experimental results provide the DLF values with the largest difference of 2.46% when the train speed varies from 0 km/h to 80 km/h

Non-Linear Dynamic Magneto Electric Effects in Ferromagnetic-Ferroelectric Layered Composites

2013 ◽  
Author(s):  
Satenik Harutyunyan ◽  
Davresh Hasanyan
Keyword(s):  
Vibration Frequency ◽  
Strain Distribution ◽  
Longitudinal Vibration ◽  
Three Dimensional ◽  
Low Frequency ◽  
Structure Design ◽  
Experimental Results ◽  
Physical Parameters ◽  
Wide Range ◽  
Non Linear

A non-linear theoretical model including bending and longitudinal vibration effects was developed for predicting the magneto electric (ME) effects in a laminate bar composite structure consisting of magnetostrictive and piezoelectric multi-layers. If the magnitude of the applied field increases, the deflection rapidly increases and the difference between experimental results and linear predictions becomes large. However, the nonlinear predictions based on the present model well agree with the experimental results within a wide range of applied electric field. The results of the analysis are believed to be useful for materials selection and actuator structure design of actuator in actuator fabrication. It is shown that the problem for bars of symmetrical structure is not divided into a plane problem and a bending problem. A way of simplifying the solution of the problem is found by an asymptotic method. After solving the problem for a laminated bar, formula that enable one to change from one-dimensional required quantities to three dimensional quantities are obtained. The derived analytical expression for ME coefficients depend on vibration frequency and other geometrical and physical parameters of laminated composites. Parametric studies are presented to evaluate the influences of material properties and geometries on strain distribution and the ME coefficient. Analytical expressions indicate that the vibration frequency strongly influences the strain distribution in the laminates, and that these effects strongly influence the ME coefficients. It is shown that for certain values of vibration frequency (resonance frequency), the ME coefficient becomes infinity; as a particular case, low frequency ME coefficient were derived as well.

Pressure Distribution in the Calendering of Plastic Materials

1951 ◽  
Vol 18 (1) ◽  
pp. 101-106
Author(s):  
J. T. Bergen ◽  
G. W. Scott
Keyword(s):  
Pressure Distribution ◽  
Viscous Liquid ◽  
High Speed ◽  
Plastic Material ◽  
The Body ◽  
Experimental Results ◽  
Distribution Characteristics ◽  
Flow Properties ◽  
Pressure Sensitive ◽  
Plastic Materials

Abstract In the calendering, or rolling, of a plastic material in to sheet form by passing it between parallel rolls, hydrostatic pressure is exerted against the surface of the roll throughout the region of contact with the plastic mass. This pressure has been measured by means of a pressure-sensitive cylinder, inserted in the body of a 10-in-diam roll, together with high-speed oscillographic technique. The materials which were calendered consisted of a resin which exhibited flow properties characteristic of a viscous liquid, and several filled plastic compositions of commercial interest. Pressure maxima ranging up to 8000 psi were observed. Comparison of experimental results with theoretical expressions for pressure distribution, as given by several authors, indicates that the equation derived by Gaskell quite satisfactorily predicts the results for the case of the viscous liquid. The commercial plastics were found to exhibit pressure-distribution characteristics which were perceptibly different from those of the viscous liquid. Certain limitations of Gaskell’s treatment of nonviscous materials prevent its application to these experimental results.

Torque Modelling and Experiment in Pelleting Process of Rotated Roll Forming

2012 ◽  
Vol 184-185 ◽  
pp. 609-613
Author(s):  
Kai Wu ◽  
Yu Sun ◽  
Bin Bin Peng
Keyword(s):  
Pressure Distribution ◽  
Powder Material ◽  
Structural Design ◽  
Experimental Results ◽  
Distribution Model ◽  
Roll Forming ◽  
Testing System ◽  
Force Model ◽  
Optimal Structural Design

First the extruding force model of isotropic powder material passing through the die hole in pelleting process was founded, then the pressure distribution model in the extruding areas was built. Based on the two models, the torque model in pelleting process of rotated roll forming was developed. The experiments were carried out on the special designed pellet mill and the wireless torque testing system was used to analysis the torque datum. It is shown the computing datum is very close to the experimental results. The researches are helpful to the optimal structural design, energy consume reduction and proper use of the pellet mill in practice.

Study of the Gas Combustion LP in an Atmospheric Burner

2008 ◽  
Author(s):  
Armando Gallegos-Mun˜oz ◽  
Armando Balderas-Bernal ◽  
Alejandro Rami´rez-Barro´n ◽  
J. C. Prince-Avelino
Keyword(s):  
Fluid Dynamic ◽  
Premixed Combustion ◽  
Experimental Results ◽  
Experimental Measurements ◽  
Finite Rate ◽  
Gas Combustion ◽  
Finite Speed ◽  
Computational Fluids Dynamics ◽  
Computational Fluids ◽  
Laminar Flamelet

The study of the gas combustion LP in an atmospheric burner to bake ceramics is presented. The study includes different models from combustion and turbulence to find the best interaction chemistry-turbulence, applying Computational Fluids Dynamics (CFD) through FLUENT®. For the study different models of combustion were considered, where the finite speed of the reaction is important by means of kinetic chemistry from Arrhenius. The different models of combustion were; a generalized model of speed of Finite Rate/Eddy dissipation, non-premixed combustion Laminar Flamelet and Eddy dissipation. Each one of these models represents the combustion non-premixed of gas LP, to simulate the combustion of turbulent diffusive flames. For the study of the turbulence the model k-epsilon was applied. The results obtained for each combination turbulence-chemistry were compared with experimental measurements of temperature within the furnace. This comparison allowed making adjustments in the modeling of the process of combustion, identifying the best interaction between combustion and turbulence. According to the obtained results, the k-epsilon model represents adequately the fluid-dynamic development of the flame within the furnace. The models of combustion Finite Rate/Eddy dissipation and Laminar Flamelet show the best approach to the experimental results, where the k-epsilon model is applied to modeling the turbulence-chemistry interaction.

Simulation of a Layered Resonator for a Microfluidic Ultrasonic Separator

2006 ◽  
Author(s):  
Yijun Shen ◽  
Mark A. Atherton
Keyword(s):  
Energy Density ◽  
Pressure Distribution ◽  
Standing Wave ◽  
Acoustic Pressure ◽  
Separation Performance ◽  
Experimental Measurements ◽  
Driving Frequency ◽  
Stored Energy ◽  
Acoustic Characteristics ◽  
Small Spherical Particle

This paper focuses on the simulation of a layered resonator for a microfluidic ultrasonic separator with a special emphasis on analysing the stored energy-frequency product in the microfluid chamber. Since the acoustic force acting on a small spherical particle in a standing wave in the cavity of an ultrasonic separator is proportional to the product of the energy density in the standing wave and the driving frequency, the energy-frequency product can be used as a prediction of the separation performance in an ultrasonic separator. The electro-acoustic characteristics of the resonator under different conditions are also investigated. In particular, the influence of the reflector thickness on the stored energy-frequency product of the layered resonator is examined. Furthermore, the acoustic pressure distribution in the fluid chamber of the ultrasonic separator is investigated in detail. Predicted results from simulations compare well with experimental measurements and show that the model can be used to predict the electro-acoustic characteristics and the separation performance.

scholarly journals Simulation of Percolation Threshold, Tunneling Distance, and Conductivity for Carbon Nanotube (CNT)-Reinforced Nanocomposites Assuming Effective CNT Concentration

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 114 ◽  
Author(s):  
Yasser Zare ◽  
Kyong Yop Rhee
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Percolation Threshold ◽  
Experimental Results ◽  
Filler Concentration ◽  
Experimental Measurements ◽  
Tunneling Conductivity ◽  
Tunneling Distance

This article suggests simple and new equations for the percolation threshold of nanoparticles, the tunneling distance between nanoparticles, and the tunneling conductivity of polymer carbon nanotubes (CNTs) nanocomposites (PCNT), assuming an effective filler concentration. The developed equations correlate the conductivity, tunneling distance, and percolation threshold to CNT waviness, interphase thickness, CNT dimensions, and CNT concentration. The developed model for conductivity is applied for some samples and the predictions are evaluated by experimental measurements. In addition, the impacts of various parameters on the mentioned terms are discussed to confirm the developed equations. Comparisons between the calculations and the experimental results demonstrate the validity of the developed model for tunneling conductivity. High levels of CNT concentration, CNT length, and interphase thickness, as well as the straightness and thinness of CNTs increase the nanocomposite conductivity. The developed formulations can substitute for the conventional equations for determining the conductivity and percolation threshold in CNT-reinforced nanocomposites.

A Rapidly Converging Theoretical Solution of the Elastohydrodynamic Problem for Rectangular Rubber Seals

1980 ◽  
Vol 22 (1) ◽  
pp. 9-16 ◽  
Author(s):  
L. E. C. Ruskell
Keyword(s):  
Pressure Distribution ◽  
Theoretical Approach ◽  
Theoretical Solution ◽  
Experimental Measurements ◽  
Rectangular Section ◽  
Rubber Seal

A theoretical approach is described which overcomes the problems of convergence previously associated with obtaining solutions of the elastohydrodynamic equations for a reciprocating, rectangular section rubber seal. Convergence of this method is extremely rapid. Results are presented which illustrate that it is suitable both for instrokes and outstrokes at realistic sealed pressures. Experimental measurements of pressure distribution are presented for comparison.

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