Thermische Simulation von Vorschubachskomponenten*/Thermal simulation of feed axis components

2015 ◽  
Vol 105 (03) ◽  
pp. 156-160
Author(s):  
C. Brecher ◽  
K. Bakarinow ◽  
S. Neus ◽  
M. Wennemer ◽  
M. Fey
Keyword(s):  
Simulation Models ◽  
Thermal Simulation ◽  
Friction Model ◽  
Wird Eine ◽  
Friction Characteristics ◽  
Feed Axis ◽  
Elastic Simulation ◽  
High Degree ◽  
Experimental Effort

Eine präzise simulative Abbildung des komplexen thermo-elastischen Maschinenverhaltens ist derzeit nur mit hohem experimentellen Aufwand möglich. Daher wird eine Methodik auf Basis analytischer Reibmodelle am Beispiel von Vorschubachskomponenten vorgestellt, welche lastabhängige Reibungskennlinien für effiziente thermo-elastische Simulationsmodelle parametriert.   An accurate simulation of the complex thermo-elastic machine behavior requires a high degree of experimental effort. Therefore, an analytical friction model is presented, which parameterizes load-dependent friction characteristics to enable efficient thermo-elastic simulation models.

Werkzeuge der ultraschallunterstützten Bearbeitung*/Modelling of an Actorsystem - Development of a tool for ultrasonic assisted machining with an axial-tangential vibration vector

2018 ◽  
Vol 108 (01-02) ◽  
pp. 53-57
Author(s):  
K. Drewle ◽  
T. Stehle ◽  
H: Möhring
Keyword(s):  
Contact Zone ◽  
Brittle Materials ◽  
Wird Eine ◽  
Alternative Method ◽  
Ultrasonic Assisted ◽  
Ultrasonic Assisted Machining ◽  
Hard And Brittle Materials ◽  
Feed Axis

Die schwingungsunterstützte Bearbeitung hat sich bereits bei der Zerspanung von hartspröden Werkstoffen mit einer einachsigen Schwingung in der Kontaktzone bewährt. Untersuchungen zu schwingungsunterstützten Bohrprozessen beschränken sich bisher auf eine Schwingungserzeugung, die entlang der Vorschubachse ausgerichtet ist. Für alternative Schwingungsrichtungen fehlt in erster Linie die geeignete Aktorik. In diesem Beitrag wird eine alternative Methode zur Erzeugung einer axial-tangentialen Schwingung in der Kontaktzone untersucht.   Ultrasonic assisted machining with uniaxial vibration is a well-proven process for machining hard and brittle materials. Existing investigations of vibration assisted drilling and boring processes so far are limited to an oscillation along the feed axis, which primarily due to nonexistent actuators. This contribution will present investigations into an alternative method for creating axial-tangential vibrations in the tool contact zone.

Quantum Approximation for Josephson's Tunneling in Thx DUO2 Nano Material for 535 Tesla at Muon Cyclotron

2013 ◽  
Vol 789 ◽  
pp. 157-160
Author(s):  
Moh. Hardiyanto
Keyword(s):  
Magnetic Field ◽  
Hadron Collider ◽  
Mathematical Formulation ◽  
Nuclear Research ◽  
Josephson Tunneling ◽  
Nuclear Research Reactor ◽  
Covariant Equation ◽  
High Degree ◽  
Quantum Condition ◽  
Experimental Effort

The convergence quantum states of free covariant equation in Einsteins space with quantum condition is studied using the ABR (Abrikosov-Balseiro-Russell) formulation in convergence approximation for Josephson tunneling is important role for determine of neutrino particle existing, especially after Cerenkovs effect for 517 tesla super magnetic at Large Hadron Collider (LHC) Cyclotron in CERN, Lyon, France based on ThxDUO2nanomaterial. This approaching will be solved the problem for determine the value of interstellar Electrical Conductivity (EC) on DUO2chain reaction, then the post condition of muon has been known exactly. In this research shown the value of EC is 4.32 μeV at 378 tesla magnetic field for 2.1 x 104ci/mm fast thermal neutron floating in 45.7 megawatts adjusted power of CERNs Cyclotron. The resulted by special Electron-Scanning-Nuclear-Absorbtion (ESNA) shown any possibilities of Josephsons tunneling must be boundary by muon particles without neutrino particle existing for 350 456 tesla magnetic field on UO2more enrichment nuclear fuel at CERN, whereas this research has purpose for provide the mathematical formulation to boundary of muons moving at nuclear research reactor to a high degree of accuracy and with Catch-Nuc, one of nuclear beam equipment has a few important value of experimental effort.

Study on Friction Characteristics of Energizing Pneumatic Cylinders

2014 ◽  
Vol 904 ◽  
pp. 306-310 ◽  
Author(s):  
Yan Jia Zhan ◽  
Tao Wang ◽  
Bo Wang
Keyword(s):  
Special Kind ◽  
Friction Model ◽  
Pneumatic Cylinder ◽  
Working Pressure ◽  
Friction Characteristics ◽  
Factors Affecting ◽  
Output Force ◽  
Experimental Apparatus ◽  
Depth Study ◽  
Pneumatic Cylinders

As a special kind of pneumatic cylinder, energizing pneumatic cylinder can increase the output force without changing diameter by a series of two or more piston on a piston rod. Since the friction characteristics of pneumatic cylinders is one of the most important factors affecting the nonlinearity, a new experimental apparatus is designed to have an in-depth study, base on exhaust throttle. The friction of energizing pneumatic cylinder was tested under different working pressure and velocity to ascertain the parameters of stribeck model. The results show that friction model of the energizing pneumatic cylinder can be the superposition of the models of each piston.

scholarly journals Analyzing Atrium Volume Designs for Hot and Humid Climates

2019 ◽  
Vol 11 (22) ◽  
pp. 6213
Author(s):  
Aram ◽  
Alibaba
Keyword(s):  
Thermal Comfort ◽  
User Satisfaction ◽  
Simulation Models ◽  
Thermal Simulation ◽  
Simulation Software ◽  
Humid Climate ◽  
High Rise ◽  
North East ◽  
Software Models ◽  
Hot And Humid Climates

The objective of this research was to determine the proper thermal comfort in an atrium design for single-floor, medium-rise, and high-rise buildings based on different proportions, placements, window opening ratios, and internal condition systems. EDSL Tas software was used for the dynamic thermal simulation software models, and all were analyzed based on ASHRAE 55, ISO 7730, and EN 15251 standards to determine which dynamic thermal simulation models had thermal comfort in a hot and humid climate throughout the year. This research found that for naturally conditioned single-floor and medium-rise buildings, when the atrium proportion was 1/2 of the office proportion at the southeast and center atrium location, respectively, had maximum user satisfaction. When the building’s internal spaces were mechanically conditioned with a 1/3 and 1/4 atrium proportion of the office proportion in single-floor and medium-rise buildings, respectively, thermal comfort was acceptable, especially when the atrium was located in the center for single-floor and in the northeast for medium-rise buildings. However, the naturally conditioned high-rise building with a north-east atrium that was 1/4 of the office proportion and a mechanically conditioned high-rise with a center atrium 1/3 of the office proportion had the minimum dissatisfaction throughout the year.

Experimental Validation of a 2D Bristle Friction Force Model

2010 ◽  
Author(s):  
Steven Fillmore ◽  
Jianxun Liang ◽  
Ou Ma
Keyword(s):  
Friction Model ◽  
Contact Friction ◽  
Force Model ◽  
Tangential Plane ◽  
Stick Slip ◽  
Friction Forces ◽  
Body Contact ◽  
Point Of Interest ◽  
Experimental Effort ◽  
Sliding Regimes

This paper describes an experimental effort designed to validate a general 2D bristle contact friction model. The model extends the 1D integrated bristle friction model to a 2D space by allowing the “bristle spring” to not only stretch along the direction of the bristle displacement but also rotate due to the instantaneous direction change of the velocity or motion trend in the common tangential plane of the contacting surfaces involved at the point of interest. The model is capable of simulating frictional behaviour in both sliding and sticking regimes occurring in general 3D rigid-body contact. With such an extension, the resulting friction model can be readily used to compute 3D contact friction forces in both sticking and sliding regimes. Two experiments were designed and implemented to validate the new 2D bristle model. The experiments were able to passively produce common frictional phenomena such as sliding, sticking, and stick-slip.

Model-Based Investigation of Friction During Start-Up of Hydrodynamic Journal Bearings

1995 ◽  
Vol 117 (4) ◽  
pp. 667-673 ◽  
Author(s):  
A. Harnoy
Keyword(s):  
Friction Model ◽  
Journal Bearings ◽  
Time Variable ◽  
Stribeck Curve ◽  
Dynamic Friction ◽  
Stick Slip ◽  
Friction Characteristics ◽  
Start Up ◽  
Variable Friction ◽  
Steady Velocity

An analysis is developed for the time-variable friction during the start-up of a rotor system. The analysis is based on a dynamic friction model that has been developed from the theory of unsteady lubrication and can describe the observed friction characteristics. The model reduces to the Stribeck curve of friction versus steady velocity, and shows hysteresis curves in oscillating velocity. The “Dahl effect” of a presliding displacement before the breakaway is also included. The results indicate that the friction characteristics and energy friction losses, during the start-up, depend on a set of dimensionless parameters that represent the bearing as well as the dynamic system. The study shows that appropriate design and operation can prevent stick-slip friction and minimize wear during start-up.

IDENTIFICATION OF THE NONLINEAR FRICTION CHARACTERISTICS IN A HYDRAULIC ACTUATOR USING THE EXTENDED KALMAN FILTER

2008 ◽  
Vol 32 (2) ◽  
pp. 121-136 ◽  
Author(s):  
Yuvin Chinniah ◽  
Richard Burton ◽  
Saeid Habibi ◽  
Eric Sampson
Keyword(s):  
Kalman Filter ◽  
Extended Kalman Filter ◽  
Quadratic Function ◽  
Friction Model ◽  
Nonlinear Friction ◽  
Hydraulic Actuator ◽  
Friction Characteristic ◽  
Piston Velocity ◽  
Friction Characteristics ◽  
Custom Made

In this paper, the nonlinear friction characteristic of a custom made symmetrical linear hydraulic actuator is investigated using the Extended Kalman Filter (EKF). A new and very accurate characterization of friction is made by using a quadratic function of the piston velocity. Further to this proposed empirical friction model, the EKF is used to estimate the function coefficients. In this paper, an iterative approach is used to maintain system observability and render the estimation process more reliable. The study is conducted in simulation and by using measured experimental data. The estimated states and parameters by the EKF are found to be convergent to their known values in simulation and, further to experimental results, unique and repeatable. In addition, changes in the friction characteristics, which can occur in the physical system due to wear in the piston seals or degradation in the oil properties, are detected and accurately estimated by the EKF in simulation. This study presents an accurate nonlinear model for the representation of friction in a hydraulic actuator. It paves the way for the implementation of strategies for early fault detection in hydraulic systems.

Friction characteristics of piston rings in a free-piston engine generator

2016 ◽  
Vol 18 (9) ◽  
pp. 871-885 ◽  
Author(s):  
Chenheng Yuan ◽  
Jing Xu ◽  
Huihua Feng ◽  
Yituan He
Keyword(s):  
Friction Model ◽  
Piston Engine ◽  
Piston Rings ◽  
Coupled Models ◽  
Free Piston ◽  
Friction Characteristics ◽  
Friction Power ◽  
Reciprocating Engine ◽  
Free Piston Engine ◽  
Insight Into

Free-piston engine generator is a new alternative to traditional reciprocating engine, which moves without mechanical restriction of crankshaft system. This article investigated numerically the friction characteristics of piston rings in a free-piston diesel engine generator by adopting coupled models of dynamic and friction. The development of the dynamic model and friction model was described, and an iterative calculation method was presented, giving insight into the coupled parameters of these two models. The detailed effects of the dynamic on friction and lubrication were investigated compared with a corresponding traditional crank engine. The friction characteristics of the free-piston engine generator were found to differ clearly from those of the traditional engine due to its special piston motion. Compared with the traditional engine, the minimum lubricant film thickness of piston rings in the free-piston engine generator is thicker and lasts shorter at the dead center regions, but it is generally thinner at other positions. The average friction force, friction power, and friction work of the piston rings in the free-piston engine generator are less than the traditional engine due to the better lubrication in endpoints region. Meanwhile, the friction power of the free-piston engine generator increases with the increase in fuel mass or decrease in load. The friction efficiency varies in correlation with the generator load; the optimum friction efficiency can be obtained by either increasing or decreasing from a certain generator load.

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