Mathematical model and experimental validation of surface profile of a workpiece in round–oval–round pass sequence

2000 ◽  
Vol 108 (1) ◽  
pp. 87-96 ◽  
Author(s):  
Y Lee ◽  
S Choi ◽  
Y.H Kim
Keyword(s):  
Mathematical Model ◽  
Experimental Validation ◽  
Surface Profile ◽  
Round Pass

scholarly journals Wave-Based Attitude Control of Spacecraft with Fuel Sloshing Dynamics

2016 ◽  
Vol 63 (2) ◽  
pp. 263-275 ◽  
Author(s):  
Joseph William Thompson ◽  
William O’Connor
Keyword(s):  
Mathematical Model ◽  
Attitude Control ◽  
Experimental Validation ◽  
Uniform Structure ◽  
Structural Flexibility ◽  
Control Laws ◽  
Single Plane ◽  
Pendulum Model ◽  
Sloshing Dynamics ◽  
Upper Stage

Abstract Wave-Based Control has been previously applied successfully to simple under-actuated flexible mechanical systems. Spacecraft and rockets with structural flexibility and sloshing are examples of such systems but have added difficulties due to non-uniform structure, external disturbing forces and non-ideal actuators and sensors. The aim of this paper is to extend the application of WBC to spacecraft systems, to compare the performance of WBC to other popular controllers and to carry out experimental validation of the designed control laws. A mathematical model is developed for an upper stage accelerating rocket moving in a single plane. Fuel sloshing is represented by an equivalent mechanical pendulum model. A wave-based controller is designed for the upper stage AVUM of the European launcher Vega. In numerical simulations the controller successfully suppresses the sloshing motion. A major advantage of the strategy is that no measurement of the pendulum states (sloshing motion) is required.

scholarly journals A Simple Model to Predict Machined Depth and Surface Profile for Picosecond Laser Surface Texturing

2018 ◽  
Vol 8 (11) ◽  
pp. 2111 ◽  
Author(s):  
Jieyu Xian ◽  
Xingsheng Wang ◽  
Xiuqing Fu ◽  
Zhengwei Zhang ◽  
Lu Liu ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Surface Texturing ◽  
Surface Profile ◽  
Picosecond Laser ◽  
Scanning Speed ◽  
Laser Surface ◽  
Laser Surface Texturing ◽  
Micro Channels ◽  
Surface Profiles ◽  
Simulation Parameters

A simple mathematical model was developed to predict the machined depth and surface profile in laser surface texturing of micro-channels using a picosecond laser. Fabrication of micro-craters with pulse trains of different numbers was initially performed. Two baseline values from the created micro-craters were used to calculate the estimated simulation parameters. Thereafter, the depths and profiles with various scanning speeds or adjacent intervals were simulated using the developed model and calculated parameters. Corresponding experiments were conducted to validate the developed mathematical model. An excellent agreement was obtained for the predicted and experimental depths and surface profiles. The machined depth decreased with the increase of scanning speed or adjacent interval.

A Study on Exhaust Muffler Using Counter-Phase Counteract

2014 ◽  
Vol 986-987 ◽  
pp. 810-813
Author(s):  
Ying Li Shao
Keyword(s):  
Mathematical Model ◽  
Experimental Validation ◽  
Noise Source ◽  
Low Frequency ◽  
Frequency Noise ◽  
Expansion Chamber ◽  
Band Noise ◽  
Exhaust Noise ◽  
Perforated Pipe ◽  
The Mathematical Model

The exhaust noise, which falls into low-frequency noise, is the dominant noise source of a diesel engines and tractors. The traditional exhaust silencers, which are normally constructed by combination of expansion chamber, and perforated pipe or perforated board, are with high exhaust resistance, but poor noise reduction especially for the low-frequency band noise. For this reason, a new theory of exhaust muffler of diesel engine based on counter-phase counteracts has been proposed. The mathematical model and the corresponding experimental validation for the new exhaust muffler based on this theory were performed.

Experimental Validation of a Dynamic Model for Flexible Link Mechanisms

2001 ◽  
Author(s):  
R. Caracciolo ◽  
A. Gasparetto ◽  
A. Trevisani
Keyword(s):  
Mathematical Model ◽  
Experimental Validation ◽  
Numerical Results ◽  
Test Case ◽  
Planar Mechanisms ◽  
Transient Period ◽  
Element Approach ◽  
Multi Body ◽  
The Mathematical Model ◽  
Good Agreement

Abstract This paper presents an experimental validation of a finite element approach for the dynamic analysis of flexible multi-body planar mechanisms. The mathematical model employed accounts for mechanism geometric and inertial non-linearities and considers coupling effects among rigid-body and elastic motion. A flexible five-bar linkage actuated by two electric motors is employed as a test case. Experimentally determined link absolute deformations are compared with the numerical results obtained simulating the system dynamic behavior through the mathematical model. The experimental and numerical results are in good agreement especially after the very first transient period.

Prestressing Steel Reinforcement Wire Bond Index Number

2013 ◽  
Author(s):  
Mark Haynes ◽  
Chih-Hang John Wu ◽  
B. Terry Beck ◽  
Naga Narendra B. Bodapati ◽  
Robert J. Peterman
Keyword(s):  
Mathematical Model ◽  
Bond Strength ◽  
Surface Profile ◽  
Steel Reinforcement ◽  
Index Number ◽  
Transfer Length ◽  
Bond Index ◽  
Prestressing Steel ◽  
Geometrical Features ◽  
The Wire

The purpose of this research project is to develop a mathematical model that predicts the bond strength of a prestressing steel reinforcement wire given the known geometrical features of the wire. The geometrical features of the reinforcement wire were measured by a precision non-contact profilometer. With this mathematical model, prestressing reinforcement wires can now be analyzed for their bond strength without destructive testing. This mathematical model has the potential to serve as a quality control assessment in reinforcement wire production. In addition this mathematical model will provide insight into which reinforcement wires provide the greatest bond strength and which combinations of geometrical features of the reinforcement wire are responsible for providing the bond strength. A precision non-contact profilometer has been developed to measure the important geometrical features of the reinforcement wire. The profilometer is capable of sub-micron resolution measurements to provide an extremely high quality three-dimensional rendering of the reinforcement wire surface profile. From this detailed profile data it is then possible to extract all of the relevant geometrical features of the reinforcement wire. A mathematical model has been created by testing a variety of different reinforcement wires available in the market. By correlating the transfer length of concrete prisms made with the reinforcement wires to various geometrical features, several different levels of mathematical correlation complexity have been investigated. The current empirical correlation models under development are first order and combine three to four unique geometrical features of the reinforcement wire which then act as predictors of the concrete prism transfer length. The resulting mathematical model relating the wire geometrical features to transfer length is referred to as the Bond Index Number (BIN). The BIN is shown to provide a numerical measure of the bond strength of prestressing steel reinforcement wire, without the need for performing destructive tests with the reinforcement wire.

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