scholarly journals ANALYSIS AND CALIBRATION OF PARAMETERS OF BUCKWHEAT GRAIN BASED ON THE STACKING EXPERIMENT

2021 ◽  
pp. 467-476
Author(s):  
Rong Fan ◽  
Qingliang Cui ◽  
Yanqing Zhang ◽  
Qi Lu
Keyword(s):  
Friction Coefficient ◽  
Static Friction ◽  
Calibration Method ◽  
Simulation Test ◽  
Physical Test ◽  
Factors Affecting ◽  
Static Friction Coefficient ◽  
Significant Difference ◽  
Simulation Parameters ◽  
Significant Factors

The stacking test based on response surface method (RSM) was carried out to calibrate the simulation parameters of buckwheat grain by discrete element method (DEM). The static friction coefficient of buckwheat-buckwheat and that of buckwheat-steel are significant factors affecting the repose angle. A quadratic polynomial model for the repose angle and the 2 significant parameters was established and optimized. The optimal combination was obtained: buckwheat-buckwheat static friction coefficient of 0.482, buckwheat-steel static friction coefficient of 0.446. It was found that there was no significant difference between the results of the simulation test and physical test (P>0.05), indicating that the parameter calibration method based on RSM is feasible. The calibrated parameters can provide reference to the simulation of buckwheat production process and machineries design.

scholarly journals Calibration and Verification of Dynamic Particle Flow Parameters by the Back-Propagation Neural Network Based on the Genetic Algorithm: Recycled Polyurethane Powder

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3350
Author(s):  
Ping He ◽  
Yiwei Fan ◽  
Banglong Pan ◽  
Yinfeng Zhu ◽  
Jing Liu ◽  
...  
Keyword(s):  
Neural Network ◽  
Genetic Algorithm ◽  
Friction Coefficient ◽  
Back Propagation ◽  
Static Friction ◽  
Discrete Element ◽  
Calibration Method ◽  
Angle Of Repose ◽  
Recovery Coefficient ◽  
Static Friction Coefficient

The discrete element method (DEM) is commonly used to study various powders in motion during transportation, screening, mixing, etc.; this requires several microscopic parameters to characterize the complex mechanical behavior of the particles. Herein, a new discrete element parameter calibration method is proposed to calibrate the ultrafine agglomerated powder (recycled polyurethane powder). Optimal Latin hypercube sampling and virtual simulation experiments were conducted using the commercial DEM software; the microscopic variables included the static friction coefficient between the particles, collision recovery coefficient, Johnson–Kendall–Roberts surface energy, static friction coefficient between the particles and wall, and collision recovery coefficient. A predictive model based on genetic-algorithm-optimized feedforward neural network (back propagation) was developed to calibrate the microscopic DEM simulation parameters. The cycle search algorithm and mean-shift cluster analysis were used to confirm the input parameters’ range by comparing the mean value of the dynamic angle of repose measured via the batch accumulation test. These parameters were verified by the baffle lifting method and the rotating drum method. This calibration method, once successfully developed, will be suitable for use in a variety of fine viscous powder dynamic flow conditions.

scholarly journals Calibration and Tests for the Discrete Element Simulation Parameters of Fallen Jujube Fruit

Agriculture ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 38
Author(s):  
Gaokun Shi ◽  
Jingbin Li ◽  
Longpeng Ding ◽  
Zhiyuan Zhang ◽  
Huizhe Ding ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Simulation Model ◽  
Static Friction ◽  
Discrete Element ◽  
Angle Of Repose ◽  
Average Error ◽  
Dem Simulation ◽  
Static Friction Coefficient ◽  
Jujube Fruit ◽  
Simulation Parameters

Discrete element method (DEM) simulation is an important method to analyze the interaction relationship between materials and equipment, and to develop machinery and/or equipment. However, it is necessary to input specific simulation parameters when establishing a DEM simulation model. In this study, the interval values were measured through angle of repose tests of fallen jujube fruit (FJF), and the simulation angle of repose tests for FJF were established with EDEM software (DEM Solutions Ltd. Edinburgh, Scotland, UK). Then, the Plackett-Burman design, steepest ascent search experiment, and center composite design experimental methods were utilized to obtain the specific values of the simulation parameters from the interval values. The results showed that significant influencing factors in the simulation angle of repose include the Poisson’s ratio, the static friction coefficient between FJF, and the static friction coefficient between FJF and the steel plate, for which the optimal values were 0.248, 0.480, and 0.309, respectively. The angle of repose tests’ results showed that the error was 0.53% between the simulation angle of repose (29.69°) and the angle of repose (29.85°). In addition, the flow rate test results showed that the average error was 5.84% between the physical and simulation tests. This indicated that the calibrated parameters were accurate and reliable, and that the simulation model can accurately represent the physical tests. Consequently, this study provides an EDEM model of FJF that was essential in designing machinery and equipment through the EDEM simulation method.

The Research of Static Friction Coefficient Measure Technology and Calibration Method for Traffic Engineering

2011 ◽  
Vol 128-129 ◽  
pp. 1493-1496 ◽  
Author(s):  
Xue Feng Ma ◽  
Dong Hua Guo ◽  
Yu Hong Lu
Keyword(s):  
Friction Coefficient ◽  
Traffic Engineering ◽  
Static Friction ◽  
Calibration Method ◽  
Inclined Plane ◽  
Plane Method ◽  
Engineering Communication ◽  
Static Friction Coefficient ◽  
Equipment System

The measure technology of static friction coefficient of traffic engineering communication and cable ducts by using inclined plane method is introduced in this paper. The calibrated method for that equipment system of static friction coefficient is discussed, furthermore.

Measurements of the Static Friction Coefficient Between Tin Surfaces and Comparison to a Theoretical Model

2011 ◽  
Vol 133 (3) ◽  
Author(s):  
Rebecca D. Ibrahim Dickey ◽  
Robert L. Jackson ◽  
George T. Flowers
Keyword(s):  
Theoretical Model ◽  
Friction Coefficient ◽  
Human Error ◽  
Surface Profile ◽  
Static Friction ◽  
Quantitative Agreement ◽  
High Plasticity ◽  
Static Friction Coefficient ◽  
Experimental Apparatus ◽  
Rough Surface Contact

A new experimental apparatus is used to measure the static friction between tin surfaces under various loads. After the data is collected it is then compared to an existing theoretical model. The experiment uses the classical physics technique of increasing the incline of a plane and block until the block slides. The angle at the initiation of sliding is used to find the static friction coefficient. The experiment utilizes an automated apparatus to minimize human error. The finite element based statistical rough surface contact model for static friction under full stick by Li, Etsion, and Talke (2010, “Contact Area and Static Friction of Rough Surfaces with High Plasticity Index,” ASME Journal of Tribology, 132(3), p. 031401) is used to make predictions of the friction coefficient using surface profile data from the experiment. Comparison of the computational and experimental methods shows similar qualitative trends, and even some quantitative agreement. After adjusting the results for the possible effect of the native tin oxide film, the theoretical and experimental results can be brought into reasonable qualitative and quantitative agreement.

scholarly journals Brittle Fracture Theory Describes the Onset of Frictional Motion

2019 ◽  
Vol 10 (1) ◽  
pp. 253-273 ◽  
Author(s):  
Ilya Svetlizky ◽  
Elsa Bayart ◽  
Jay Fineberg
Keyword(s):  
Friction Coefficient ◽  
Brittle Fracture ◽  
Static Friction ◽  
Quantitative Agreement ◽  
Interface Fracture ◽  
Earthquake Dynamics ◽  
Rupture Dynamics ◽  
Static Friction Coefficient ◽  
Fracture Theory ◽  
Macroscopic Motion

Contacting bodies subjected to sufficiently large applied shear will undergo frictional sliding. The onset of this motion is mediated by dynamically propagating fronts, akin to earthquakes, that rupture the discrete contacts that form the interface separating the bodies. Macroscopic motion commences only after these ruptures have traversed the entire interface. Comparison of measured rupture dynamics with the detailed predictions of fracture mechanics reveals that the propagation dynamics, dissipative properties, radiation, and arrest of these “laboratory earthquakes” are in excellent quantitative agreement with the predictions of the theory of brittle fracture. Thus, interface fracture replaces the idea of a characteristic static friction coefficient as a description of the onset of friction. This fracture-based description of friction additionally provides a fundamental description of earthquake dynamics and arrest.

scholarly journals A Novel Process for Manufacturing High-Friction Rings with a Closely Defined Coefficient of Static Friction (Relative Standard Deviation 3.5%) for Application in Ship Engine Components

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 448
Author(s):  
Wojciech S. Gora ◽  
Jesper V. Carstensen ◽  
Krystian L. Wlodarczyk ◽  
Mads B. Laursen ◽  
Erica B. Hansen ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Friction Coefficient ◽  
Relative Standard Deviation ◽  
Static Friction ◽  
Laser Surface ◽  
Laser Surface Texturing ◽  
Textured Surface ◽  
Fibre Lasers ◽  
Static Friction Coefficient ◽  
Relative Standard

In recent years, there has been an increased uptake for surface functionalization through the means of laser surface processing. The constant evolution of low-cost, easily automatable, and highly repeatable nanosecond fibre lasers has significantly aided this. In this paper, we present a laser surface-texturing technique to manufacture a surface with a tailored high static friction coefficient for application within driveshafts of large marine engines. The requirement in this application is not only a high friction coefficient, but a friction coefficient kept within a narrow range. This is obtained by using nanosecond-pulsed fibre lasers to generate a hexagonal pattern of craters on the surface. To provide a suitable friction coefficient, after laser processing the surface was hardened using a chromium-based hardening process, so that the textured surface would embed into its counterpart when the normal force was applied in the engine application. Using the combination of the laser texturing and surface hardening, it is possible to tailor the surface properties to achieve a static friction coefficient of ≥0.7 with ~3–4% relative standard deviation. The laser-textured and hardened parts were installed in driveshafts for ship testing. After successfully performing in 1500 h of operation, it is planned to adopt the solution into production.

scholarly journals Active Sensing of Static Friction Coefficient ^|^mu; for Controlling Grasping Force

1994 ◽  
Vol 30 (10) ◽  
pp. 1188-1194 ◽  
Author(s):  
Youji YAMADA ◽  
Kenji SANDA ◽  
Kazuhide FUJITA ◽  
Nuio TSUCHIDA ◽  
Kouji IMAI
Keyword(s):  
Friction Coefficient ◽  
Static Friction ◽  
Active Sensing ◽  
Static Friction Coefficient ◽  
Grasping Force
Sign in / Sign up

Export Citation Format

Share Document