Study on the dynamic vibration characteristics of viscoelastic yarn bundles

2018 ◽  
Vol 89 (18) ◽  
pp. 3744-3751
Author(s):  
Yang Xu ◽  
Furong Cheng ◽  
Xiaowei Sheng ◽  
Li Angang ◽  
Ahmadou Bamba Sourang Thiaw
Keyword(s):  
Experimental Data ◽  
Transverse Vibration ◽  
Vibration Characteristics ◽  
Axial Motion ◽  
Vibration Equation ◽  
Dynamic Vibration ◽  
Vibration Model ◽  
Galerkin Truncation ◽  
Creep Models ◽  
Simulation Results

In order to study the influence of yarn bundle vibration characteristics on the vibration and noise of tufted carpet looms, a yarn bundle vibration model was proposed in this paper, which was based on the viscoelasticity of the yarn bundle, and the correctness of the transverse vibration equation of the yarn bundle was verified by experiments. Different creep models of the yarn bundle were fitted with the experimental data, and the transverse vibration equation of the axial motion viscoelastic yarn bundle was established by using Burgers four-element constitutive model. Then, the Galerkin truncation method was used to solve the partial differential vibration equation of the yarn bundle and solve the equation. Finally, the correctness of the vibration equation is verified by comparison between the experimental results and the numerical simulation results. The results show that the vibration equation is suitable for studying the transverse dynamic vibration characteristics of the yarn bundle.

Research on Vibration Characteristics of Barrel Considered Gas Pressure

2015 ◽  
Vol 727-728 ◽  
pp. 501-504 ◽  
Author(s):  
Da Wei Zhu ◽  
Jie Zhou ◽  
Xue Ping Zhang
Keyword(s):  
Transverse Vibration ◽  
Great Influence ◽  
Forced Response ◽  
Vibration Characteristics ◽  
Gas Pressure ◽  
Charge Weight ◽  
Considerable Influence ◽  
Analysis Method ◽  
Vibration Equation ◽  
Simulation Results

The vibration of barrel has considerable influence on accuracy when firing, for obtaining the disciplinarian of barrel vibration, barrel is considered as a cantilever in this paper, on that base, its transverse vibration equation has been established, and forced response can be figured out by using modal analysis method. The vibration characteristics of barrel were numerically simulated for different charge weight, besides, two situations that the barrel with or without gas pressure have been compared. In solving process, the displacement、velocity and acceleration of projectile are real dates. The simulation results indicate that static offset has a great influence on vibration characteristics, with the increasing of the projectile′s initializing speed, the amplitude of the barrel′s vibration is lower without static offset, and the effect of gas pressure can decrease the amplitude of vibration considerably.

Vibration characteristics of yarn in the tufted carpet machine

2018 ◽  
Vol 89 (17) ◽  
pp. 3567-3577
Author(s):  
Huang Shuang ◽  
Xu Yang
Keyword(s):  
Differential Equation ◽  
Transverse Vibration ◽  
Vibration Characteristics ◽  
Second Law ◽  
Vibration Characteristic ◽  
Vibration Equation ◽  
Runge Kutta Method ◽  
Reasonable Range ◽  
Galerkin Truncation

To control the yarn vibration in a reasonable range and to improve the quality of tufted carpet, it is very important to understand the vibration characteristics of yarn correctly. The transverse vibration equation of yarn is established using Newton’s second law in different paths, and then the yarn vibration characteristic curves in different regions are obtained. Firstly, the yarn path is divided and the optimal constitutive model of tufted carpet yarn is determined. Secondly, the transverse vibration is built by analyzing the force of yarn means. Then, the partial differential equation of yarn vibration is simplified as an ordinary differential equation by the Galerkin truncation method. The equation is solved numerically by using the Runge–Kutta method, obtaining the yarn amplitude in different regions. The vibration characteristics of the yarns after the jacquard parts are emphatically analyzed, and the effects of the speed, tension and damping coefficient on the vibration characteristics of yarns are also discussed. Finally, the results are verified by experiments.

scholarly journals Vibration Characteristics for Moving Printing Membrane with Variable Density along the Lateral Direction

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Mingyue Shao ◽  
Jimei Wu ◽  
Yan Wang ◽  
Qiumin Wu ◽  
Yuan Chen
Keyword(s):  
Density Distribution ◽  
Transverse Vibration ◽  
High Speed ◽  
Differential Quadrature Method ◽  
Variable Density ◽  
Vibration Characteristics ◽  
Lateral Direction ◽  
Vibration Model ◽  
The Stability ◽  
Density Coefficient

The vibration model of moving membrane with variable density distribution is established, and the density distribution of the moving membrane varies along the lateral direction. The transverse vibration differential equations of moving membrane are established based on D’Alembert’s principle and discretized by using the differential quadrature method (DQM). The relationships of the first three dimensionless complex frequencies between dimensionless speed, density coefficient, and tension ratio of the membrane are analyzed by numerical calculation. The effects of the density coefficient and the tension ratio on transverse vibration characteristics of the membrane are investigated. The relationship between density coefficient and critical speed is obtained. The numerical results show that the density coefficient and the tension ratio have important influence on the stability of moving membrane. So the study provides a theoretical basis for improving the working stability of the membrane in the high-speed printing process.

scholarly journals Spatial Transverse Vibration Simulation Model of Axially Moving Sucker Rod String under the Excitation of Curved Borehole

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Hongbo Wang ◽  
Shimin Dong
Keyword(s):  
Transverse Vibration ◽  
Axial Load ◽  
Simulation Models ◽  
Elastic Collision ◽  
Axial Motion ◽  
Runge Kutta Method ◽  
Sucker Rod ◽  
Simulation Results ◽  
Axially Moving ◽  
Vibration Simulation

The mechanical model of transverse vibration of sucker rod string (SRS) in directional well is simplified to the transverse vibration model of longitudinal and transverse curved beam with initial bending under borehole constraints. In this paper, besides considering the excitation of alternating axial load on the transverse vibration of SRS, it is proposed for the first time that curved borehole is also the main excitation for the transverse vibration when the SRS moves reciprocating axially in the borehole. Based on the elastic body vibration theory, the transverse vibration mathematical model of SRS with initial bending under borehole constraints is established. In this model, the curved borehole excitation caused by the axial motion and the alternating axial load excitation is considered. Besides, the elastic collision theory is applied to describe the constraint of tube on the SRS transverse vibration in this model. Then the fourth-order Runge–Kutta method is used to calculate the transverse vibration of SRS in directional wells. The simulation results show the following: (1) The simulation results of the three simulation models in this paper are different. The results indicate that the curved borehole excitation caused by the axial motion and the alternating axial load excitation is the main excitation for the SRS transverse vibration. (2) In directional wells, the rod and tube contact along the well depth, and the dangerous sections locate at the deviation section of the borehole and the compression section of the rod. On the whole, the contact force between rod and tube in deviation section of borehole is larger. The transverse vibration of the compression section of the rod is the most violent.

BEHAVIORAL MODEL OF A LINEAR VOLTAGE STABILIZER IN THE SPICE LANGUAGE

2019 ◽  
Author(s):  
Aleksey Malahanov
Keyword(s):  
Experimental Data ◽  
Behavioral Model ◽  
Voltage Stabilizer ◽  
Static Mode ◽  
Technical Description ◽  
Simulation Results ◽  
Chip Manufacturer ◽  
Linear Voltage

A variant of the implementation of the behavioral model of a linear voltage stabilizer in the Spice language is presented. The results of modeling in static mode are presented. The simulation results are compared with experimental data and technical description of the chip manufacturer.

scholarly journals Realization of a fractional-order RLC circuit via constant phase element

2021 ◽  
Author(s):  
Riccardo Caponetto ◽  
Salvatore Graziani ◽  
Emanuele Murgano
Keyword(s):  
Experimental Data ◽  
Carbon Black ◽  
Fractional Order ◽  
Constant Phase Element ◽  
Polymeric Matrix ◽  
Fractional Order Systems ◽  
New Device ◽  
Rlc Circuit ◽  
Simulation Results

AbstractIn the paper, a fractional-order RLC circuit is presented. The circuit is realized by using a fractional-order capacitor. This is realized by using carbon black dispersed in a polymeric matrix. Simulation results are compared with the experimental data, confirming the suitability of applying this new device in the circuital implementation of fractional-order systems.

scholarly journals Investigation of the Thickness Differential on the Formability of Aluminum Tailor Welded Blanks

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 875
Author(s):  
Jie Wu ◽  
Yuri Hovanski ◽  
Michael Miles
Keyword(s):  
Experimental Data ◽  
Finite Element ◽  
Numerical Model ◽  
Plastic Strain ◽  
Finite Element Model ◽  
Equivalent Plastic Strain ◽  
Element Model ◽  
Dome Height ◽  
Tailor Welded Blanks ◽  
Simulation Results

A finite element model is proposed to investigate the effect of thickness differential on Limiting Dome Height (LDH) testing of aluminum tailor-welded blanks. The numerical model is validated via comparison of the equivalent plastic strain and displacement distribution between the simulation results and the experimental data. The normalized equivalent plastic strain and normalized LDH values are proposed as a means of quantifying the influence of thickness differential for a variety of different ratios. Increasing thickness differential was found to decrease the normalized equivalent plastic strain and normalized LDH values, this providing an evaluation of blank formability.

Sheet Material Property Effects upon Dynamic Behavior in Self-Pierce Riveted Joints

2011 ◽  
Vol 675-677 ◽  
pp. 999-1002 ◽  
Author(s):  
Xiao Cong He
Keyword(s):  
Natural Frequency ◽  
Transverse Vibration ◽  
Spot Welding ◽  
Sheet Material ◽  
Vibration Characteristics ◽  
Efficient Design ◽  
Material Density ◽  
Sheet Materials ◽  
Riveted Joints ◽  
Free Transverse Vibration

Self-pierce riveting (SPR) technology offers an alternative to resistance spot welding (RSW) for joining sheet materials. It has been found that the SPR technology produced a much stronger joint than the RSW in fatigue test. For efficient design of SPR structures, the knowledge of dynamic characteristics of the SPR beams is essential. In this paper, the free transverse vibration characteristics of single lap-jointed cantilevered SPR beams are investigated in detail. The focus of the analysis is to reveal the influence on the natural frequency and natural frequency ratio of these beams caused by variations in the material properties of sheet materials to be jointed. It is shown that the transverse natural frequencies of single lap jointed cantilevered SPR beams increase significantly as the Young’s modulus of the sheet materials increases, but change slightly corresponding to the change in Poisson’s ratio. It is also found that the material density of the sheets have significant effects on the free transverse vibration characteristics of the beams.

Wear of a Tool in Double-Disk Lapping of Silicon Wafers

2010 ◽  
Author(s):  
Adam Barylski ◽  
Mariusz Deja
Keyword(s):  
Experimental Data ◽  
Integrated Circuits ◽  
Tool Wear ◽  
Silicon Wafers ◽  
Silicon Ingot ◽  
Proposed Model ◽  
Tool Wear Prediction ◽  
Simulation Results ◽  
High Degree ◽  
Kinematical Parameters

Silicon wafers are the most widely used substrates for fabricating integrated circuits. A sequence of processes is needed to turn a silicon ingot into silicon wafers. One of the processes is flattening by lapping or by grinding to achieve a high degree of flatness and parallelism of the wafer [1, 2, 3]. Lapping can effectively remove or reduce the waviness induced by preceding operations [2, 4]. The main aim of this paper is to compare the simulation results with lapping experimental data obtained from the Polish producer of silicon wafers, the company Cemat Silicon from Warsaw (www.cematsil.com). Proposed model is going to be implemented by this company for the tool wear prediction. Proposed model can be applied for lapping or grinding with single or double-disc lapping kinematics [5, 6, 7]. Geometrical and kinematical relations with the simulations are presented in the work. Generated results for given workpiece diameter and for different kinematical parameters are studied using models programmed in the Matlab environment.

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