Study on Electrical Automation with Design of the Constant-Precision Frequency Meter Based on MCU and CPLD

2013 ◽  
Vol 703 ◽  
pp. 269-272
Author(s):  
Xiao Yang ◽  
Yu Wen Zhai
Keyword(s):  
Relative Error ◽  
Frequency Measurement ◽  
Measurement Precision ◽  
Gate Time ◽  
Frequency Meter ◽  
Simulation Results ◽  
Precision Frequency ◽  
Relationship Of ◽  
The Relationship

According to the principle of constant-precision frequency measurement in the field of electrical automation, the relationship of frequency measurement precision and gate time is analyzed. And the constant-precision frequency meter based on MCU and CPLD is designed in this paper. It can keep the relative error being 0.0001% constantly when frequency measuring within the range of 0.1Hz to 1MHz. Its simulation results by MUX+PLUS is presented.

A Novel Trans-Scale Precision Positioning Stage Based on the Stick-Slip Effect

2012 ◽  
Vol 2 (2) ◽  
pp. 1-14 ◽  
Author(s):  
Bowen Zhong ◽  
Liguo Chen ◽  
Zhenhua Wang ◽  
Lining Sun
Keyword(s):  
Friction Model ◽  
Slip Effect ◽  
Precision Positioning ◽  
Stick Slip ◽  
Kinematics Model ◽  
Lugre Friction Model ◽  
Positioning Stage ◽  
Simulation Results ◽  
Relationship Of ◽  
The Relationship

This article focuses on developing a novel trans-scale precision positioning stage based on the stick-slip effect. The stick-slip effect is introduced and the rigid kinematics model of the stick-slip driving is established. The forward and return displacement equations of each step of the stick-slip driving are deduced. The relationship of return displacement and the acceleration produced by friction are obtained according to displacement equations. Combining with LuGre friction model, the flexible dynamics model of the stick-slip driving is established and simulated by using Simulink software. Simulation results show that the backward displacement will reduce with the acceleration of the slider produced by dynamic friction force, the rigid kinematics model is also verified by simulation results which are explained in further detail in the article.

Study on the Relationship of Airbag Effect and Occupant Position

2011 ◽  
Vol 299-300 ◽  
pp. 1279-1282
Author(s):  
Xiu Chunb Wu ◽  
Kun Li ◽  
Bo Wang ◽  
Xue Shenc Su
Keyword(s):  
Computer Simulation ◽  
Traffic Accident ◽  
Simulation Method ◽  
Simulation Test ◽  
Computer Simulation Method ◽  
Simulation Results ◽  
Relationship Of ◽  
The Relationship

Computer simulation method is used to study the relations of airbag effect and occupant position. By changing the position of 50% dummy model to achieve the purpose of changing the position between airbag and occupant, three kinds of simulation test are made, and the simulation results are analyzed and compared. It is shown that between the belted occupant and airbag exists such a position or distance, at which the injury to occupant is the smallest when the traffic accident happens.

Research on the Relationship of Flow Velocity and Particles’ Separation in Cyclone

2012 ◽  
Vol 479-481 ◽  
pp. 2529-2532
Author(s):  
Ying Zhang ◽  
Zhen Wei Zhang
Keyword(s):  
Numerical Simulation ◽  
Velocity Distribution ◽  
Flow Velocity ◽  
Structure Design ◽  
Rotating Flow ◽  
Separation Performance ◽  
Simulation Results ◽  
Relationship Of ◽  
The Relationship ◽  
Distribution Of Flow

This paper mainly focuses on the numerical simulation of flow velocity aiming to obtain the velocity distribution of flow in the cyclone. The authors took advantage of RSM turbulence model of software FLUENT to calculate the velocity distribution. Relationship between particles separation and double-layer rotating flow can be obtained based on the simulation results, which can also provide basis for the improvement of structure design and separation performance.

Highway Alignment Parameters Design and Capacity Analysis on Two-Lane Highway

2014 ◽  
Vol 539 ◽  
pp. 860-866
Author(s):  
Jiang Liu
Keyword(s):  
Capacity Analysis ◽  
Horizontal Curve ◽  
Mountainous Areas ◽  
Key Factors ◽  
Horizontal Curves ◽  
Percent Time ◽  
Simulation Results ◽  
Relationship Of ◽  
Highway Alignment ◽  
The Relationship

A two-lane highway is an undivided highway with only one lane of traffic in each direction. Two-lane highways are one of the most common roadways at mountainous areas in China. Due to the wider range to choose the horizontal and vertical curves in the design of two-lane highways, the combination of both leads to larger differences on two-lane highway capacities. Thus, the highway alignments are one of the key factors which affect the two-lane highway capacities. According to the empirical data and existing studies, it is regarded that there is no impacts on the capacity for horizontal curves with a radius more than 400m and vertical curves with the gradient less than 3%. Two concepts are defined as effective bending and effective gradient which represent the extent the horizontal curve bends and the steepness of vertical curve respectively. The method to calculate effective bending of horizontal curve and steepness of vertical curve is given and its relevant properties are also discussed. According to the simulation results and the principle of speed differences, the effective bending and effective gradient have been classified into 7 and 6 levels, separately. As a result, there will be 42 combinations of different highway alignments of two-lane highways based on the different combinations of the effective bending and effective gradient. Under this circumstance, the relationship of speed-volume and volume-PTSF (percent time spend following) are obtained from the simulation results. Finally, the capacity of two-lane highway is given under different highway alignments of two-lane highway at mountainous areas in China.

STUDY OF CUTTING AERIAL PMMA WITH MINIATURE DETONATION CORD

2008 ◽  
Vol 22 (31n32) ◽  
pp. 5566-5571
Author(s):  
Z.Q. LI ◽  
L.M. ZHAO ◽  
Y.G. ZHAO
Keyword(s):  
Experimental Study ◽  
Dynamic Analysis ◽  
Nonlinear Dynamic ◽  
Linear Density ◽  
Nonlinear Dynamic Analysis ◽  
Plate Versus ◽  
Cutting Depth ◽  
Simulation Results ◽  
Relationship Of ◽  
The Relationship

In order to shorten the time of through-the-canopy-ejection, and to ensure pilot safely escape and survive. The application of linear cutting technique using miniature detonation cord( MDC) in through-the-canopy-ejection-system is proposed. A series of different kinds of MDC are designed. Firstly experimental study on the cutting process of the PMMA plate wiht MDC is carried out. Material of metal cover explosive types and the range of charge quantities are determined. Consequently the phenomena of spallation is observed, and the relationship between the cutting depth and charge quantities is obtained. For the comparison, the process of explosion cutting PMMA plate is simulated by means of nonlinear dynamic analysis code LS-DYNA. Spallation phenomena which occurs in the experiment, is also observed in the simulation. Simulation results present the relationship of cutting depth of PMMA plate versus charge linear density, which well agree with experimental ones.

The Research about the Vibroacoustic Characteristics of the Surface Cracked Plate

2014 ◽  
Vol 602-605 ◽  
pp. 303-310
Author(s):  
Gui Jie Liu ◽  
Meng Meng Li ◽  
Yu Qian Wang ◽  
Yu Zhan Yuan
Keyword(s):  
Theoretical Formula ◽  
Spring Model ◽  
Cracked Plate ◽  
Structural Intensity ◽  
Line Spring Model ◽  
Simulation Results ◽  
Shell Finite Element ◽  
Vibration Parameters ◽  
Relationship Of ◽  
The Relationship

Vibration characteristics of surface cracked plate are studied from the view of structural intensity .Line-spring model of the surface crack is put forward based on fracture mechanics. The relationship of the additional angle and displacement with the crack parameters is derived. The concept of additional structural intensity is presented and the additional structural intensity’s expression of shell finite element is deduced. The change regulars between structural intensity and vibration parameters with crack’s parameters are concluded by using ANSYS and MATLAB software, the simulation results are matched with the trend of theoretical formula.

The Numerical Simulation of Air-Cooled Plate-Fin Heat Exchanger

2011 ◽  
Vol 314-316 ◽  
pp. 1472-1477 ◽  
Author(s):  
Xue Jiang ◽  
Ji Hua Bao ◽  
Yan Yu ◽  
Ming Xia Gu
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Heat Exchanger ◽  
3D Model ◽  
Fluid Velocity ◽  
Heat Transfer Characteristics ◽  
Flow And Heat Transfer ◽  
Simulation Results ◽  
Relationship Of ◽  
The Relationship

According to the periodic structure of the plate-fin heat exchanger, 3D model of the heat exchanger is established which simplifies the computation amount of the numerical simulation on flow field and temperature field. The relationship of fluid velocity, temperature, pressure drop and heat transfer coefficient is analyzed. The flow and heat transfer characteristics can be well predicted. Based on the simulation results, the conclusion makes reference to the design of plate-fin heat exchanger.

Research on LED multi-sector stable display model in variable rotational speed

2021 ◽  
pp. 1-11
Author(s):  
Luhong Lang ◽  
Dong Ma ◽  
Jun Dong ◽  
Junming He ◽  
Panpan Xu ◽  
...  
Keyword(s):  
Rotational Speed ◽  
Linear Array ◽  
Noise Pollution ◽  
Frequency Measurement ◽  
Stepping Motor ◽  
Term Operation ◽  
Speed Fluctuation ◽  
Precision Frequency ◽  
The Relationship

To solve the display distortion caused by the motor rotational speed changes in the long-term operation of the rotating LED multi-sector display system，the model for LED multi-sector stable display (MSSD) in variable rotational speed is proposed based on the principle of visual persistence. The stepping motor subdivision driving technology is applied to the rotating LED multi-sector display, and the equal precision frequency measurement method is used for accurate rotational speed measurement. Then the innovation adaptive kalman filter (IAKF) is researched to further enhance the robustness to eliminate noise pollution, and the relationship between the modification value caused by rotational speed and the LED linear array minimum refresh time is analysed. The rotating LED MSSD system based on LED linear array rotated by stepping motor is provided. The test results reveal the relationship between rotational speed and the LED linear array minimum refresh time, and show that the lighting position of the LED can be synchronized with the lighting state during the rotational speed fluctuation, and the error can be controlled to a low level via LED linear array minimum refresh time correction．The designed model can effectively eliminate the distortion of the rotating LED multi-sector display screen caused by the changes of the motor rotational speed, and has a very stable display effect.

Fast Prediction Model for Closure Pressure in Hot Isostatic Pressing

2014 ◽  
Vol 887-888 ◽  
pp. 1240-1245
Author(s):  
Dong Qiao Zhang ◽  
Jian Xin Zhou ◽  
Jun Li Tang ◽  
Hong Wang
Keyword(s):  
Prediction Model ◽  
Relative Error ◽  
Hot Isostatic Pressing ◽  
Commercial Software ◽  
Isostatic Pressing ◽  
Fast Prediction ◽  
Relationship Of ◽  
The Relationship ◽  
Complex Casting ◽  
Hip Process

Simulation of hot isostatic pressing (HIP) process with complex castings was rarely referred for its time-consuming and difficulties existed in meshing by commercial software. A fast prediction model was proposed to overcome those limitations in present work. The relationship of holes size, shape, and closure pressure was established by analysing the closed hole in ZTC4 castings with simple structures based on the software. Then the fast prediction model was applied to a complex casting. A relative error of 4.09% was obtained between this model and result calculated by the software, which verified its effectiveness in predicting ZTC4 castings with complicated structures.

Deformation Behaviors and Critical Parameters in Microscale Laser Dynamic Forming

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
Huang Gao ◽  
Chang Ye ◽  
Gary J. Cheng
Keyword(s):  
Critical Parameters ◽  
Thin Foils ◽  
Deformation Behaviors ◽  
Microfabrication Technique ◽  
Simulation Results ◽  
Relationship Of ◽  
The Relationship ◽  
Method Model ◽  
Ultrahigh Strain

Microscale laser dynamic forming (μLDF) is a novel microfabrication technique to introduce complex 3D profiles in thin films. This process utilizes pulse laser to generate plasma to induce shockwave pressure into the thin film, which is placed above a microsized mold. The strain rate in μLDF reaches 106–107 S−1. Under these ultrahigh strain rates in microscale, deformation behaviors of materials are very complicated and almost impossible to be measured in situ experimentally. In this paper, a finite element method model is built to simulate the μLDF process. An improved Johnson–Cook model was used to calculate the flow stress, and the Johnson–Cook failure criterion was employed to simulate failure during μLDF. The simulation results are validated by experiments, in which the deformation of Cu thin foils after μLDF experiments are characterized by scanning electron microscopy and compared with simulation results. With the verified model, the ultrafast μLDF process is generally discussed first. A series of numerical simulations are conducted to investigate the effects of critical parameters on deformation behaviors. These critical parameters include the ratio of the fillet radius to film thickness, the aspect ratio of mold, as well as laser intensities. The relationship of laser pulse energy and the deformation depth is also verified by a series of μLDF experiments.

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