Study on oscillation modes of weld pool in stationary GTA welding using structure laser method

Abstract To study the oscillation mode of GTA weld pool, the oscillation mode of weld pool was analyzed based on Bessel equation, and the laser dot matrix images of (0, 1), (1, 1), (2, 1), (0, 2) oscillation modes at different times are obtained by structured laser optical measurement simulation. The oscillation mode of stationary GTA weld pool was analyzed based on the laser dot matrix images obtained by structure laser experiment. The result shows the simulated laser dot matrix images matches up to the experiment result. The oscillation mode of the weld pool can be recognized based on laser dot matrix image. This study can not only provide conditions for judging the penetrating state of weld pool, but also help to further understand the oscillation mode of the weld pool and develop more effective observation methods and measurement tools, so as to effectively control and improve the welding quality.

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Oscillation Modes of Weld Pool in Stationary GTA Welding Using Structure Laser Method

Chinese Journal of Mechanical Engineering ◽

10.1186/s10033-021-00609-9 ◽

2021 ◽

Vol 34 (1) ◽

Author(s):

Xingpei Wu ◽

Jiankang Huang ◽

Jing He ◽

Shien Liu ◽

Guangyin Liu ◽

...

Keyword(s):

Weld Pool ◽

Optical Measurement ◽

Capital Expenditure ◽

Three Dimensional ◽

Oscillation Mode ◽

Gta Welding ◽

Simulation Software ◽

Laser Method ◽

Oscillation Modes ◽

Structure Laser

AbstractResearchers have recently attempted to monitor pool oscillations using the three-dimensional laser vision method. However, the deficiency of simulation software will result in significant capital expenditure. Both simulations and experiments are performed in this study, and the Bessel equation is used to analyze the oscillation mode of a weld pool. The laser dot matrix images of (0, 1), (1, 1), (2, 1), and (0, 2) oscillation modes at different times are obtained via structured laser optical measurement simulation. The oscillation mode of a stationary gas tungsten arc weld pool is analyzed based on laser dot matrix images obtained from a structure laser experiment. Results show that the simulated laser dot matrix images are consistent with the experiment results. The oscillation mode of the weld pool can be recognized based on the laser dot matrix image. This study not only provides conditions for assessing the penetrating state of a weld pool, but also enable a further understanding of the oscillation mode of a weld pool and the development of more effective observation methods and measurement tools to effectively control and improve welding quality.

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The oscillation of stationary weld pool surface in the GTA welding

Journal of Materials Processing Technology ◽

10.1016/j.jmatprotec.2018.01.018 ◽

2018 ◽

Vol 256 ◽

pp. 57-68 ◽

Cited By ~ 15

Author(s):

J.K. Huang ◽

M.H. Yang ◽

J.S. Chen ◽

F.Q. Yang ◽

Y.M. Zhang ◽

...

Keyword(s):

Weld Pool ◽

Gta Welding ◽

Pool Surface ◽

Weld Pool Surface

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Optical Measurement of Surface Temperature Distribution of Weld Pool in AC Tungsten Inert Gas Welding of Aluminum A1050

Journal of Smart Processing ◽

10.7791/jspmee.8.213 ◽

2019 ◽

Vol 8 (5) ◽

pp. 213-218

Author(s):

Quang Ngoc TRINH ◽

Huy Le PHAN ◽

Shinichi TASHIRO ◽

Van Hanh BUI ◽

Manabu TANAKA

Keyword(s):

Temperature Distribution ◽

Surface Temperature ◽

Weld Pool ◽

Optical Measurement ◽

Inert Gas ◽

Tungsten Inert Gas Welding ◽

Surface Temperature Distribution

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Effect of Large-Scale Wind Power Integration on Inter-Area Oscillation of Power System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.672-674.227 ◽

2014 ◽

Vol 672-674 ◽

pp. 227-232

Author(s):

Xu Zhi Luo ◽

Hai Feng Li ◽

Hua Dong Sun ◽

An Si Wang ◽

De Zhi Chen

Keyword(s):

Power Systems ◽

Power System ◽

Wind Power ◽

Large Scale ◽

Oscillation Mode ◽

Equivalent Model ◽

Synchronous Generators ◽

Actual System ◽

Oscillation Modes ◽

The Impact

With the fast development of the wind power, security constraints of power systems have become the bottleneck of the acceptable capacity for wind power. The underdamping oscillation modes of the inter-area is an important aspect of the constraints. In this paper, an equivalent model of a power system with wind plants has been established, and the impact of the integration of the large-scale wind power on the inter-area oscillation modes has been studied based on the frequency-domain and time-domain simulations. The results indicate that the damping of inter-area oscillation mode can be enhanced by the replacement of synchronous generators (SGs) with the wind generators. The enhancing degree is up to the participation value of the SGs replaced. The conclusion has been verified by the actual system example of Xinjiang-Northwest grid. It can provide a reference for system programming and operation.

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Power System Oscillation Modes Identifications: Guidelines for Applying TLS-ESPRIT Method

International Journal of Emerging Electric Power Systems ◽

10.1515/ijeeps-2013-0023 ◽

2013 ◽

Vol 14 (1) ◽

pp. 57-66 ◽

Cited By ~ 6

Author(s):

Gopal R. Gajjar ◽

Shreevardhan Soman

Keyword(s):

Power System ◽

Oscillation Mode ◽

Area Measurement ◽

Wide Area ◽

Mode Identification ◽

Measurement Systems ◽

Electromechanical Oscillations ◽

Direct Observations ◽

Oscillation Modes ◽

Selection Of

Abstract Fast measurements of power system quantities available through wide-area measurement systems enables direct observations for power system electromechanical oscillations. But the raw observations data need to be processed to obtain the quantitative measures required to make any inference regarding the power system state. A detailed discussion is presented for the theory behind the general problem of oscillatory mode indentification. This paper presents some results on oscillation mode identification applied to a wide-area frequency measurements system. Guidelines for selection of parametes for obtaining most reliable results from the applied method are provided. Finally, some results on real measurements are presented with our inference on them.

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Heat Transfer Modelling and Investigation of the Effect of Pulse Frequency and Current in Pulsed Current Gas Tungsten Arc Welding

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.592-594.395 ◽

2014 ◽

Vol 592-594 ◽

pp. 395-399

Author(s):

A. Prabakaran ◽

R. Sellamuthu ◽

Sanjivi Arul

Keyword(s):

Heat Transfer ◽

Weld Pool ◽

Arc Welding ◽

Gta Welding ◽

Gas Tungsten Arc Welding ◽

Transfer Model ◽

Pulsed Current ◽

Current Frequency ◽

Gas Tungsten Arc ◽

Gas Tungsten

Gas Tungsten Arc Welding (GTAW) involves several process parameters. In Pulsed Current GTAW frequency of pulse and pulse to time ratio differentiates the characteristics of weld pool geometry of from GTAW. In the present work a simple heat transfer model for Pulsed Current GTA welding was developed and the weld pool dimensions were experimentally verified with AISI 1020 steel. Relationship between speed and pulsed current frequency on weld pool dimension was studied. Weld pool dimension of pulsed and non-pulsed GTAW is studied.

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Quadratic and Cubic Couplings of Oscillation Modes of Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100037131 ◽

1995 ◽

Vol 155 ◽

pp. 287-288

Author(s):

T. Van Hoolst

Keyword(s):

Main Sequence ◽

Oscillation Mode ◽

The Self ◽

Nonlinear Interactions ◽

Nonlinear Coupling ◽

Coupling Coefficients ◽

Main Sequence Stars ◽

Evolved Stars ◽

Oscillation Modes ◽

Nonradial Oscillation

The strength of nonlinear interactions of oscillation modes of stars is determined by the amplitudes as well as by the eigenfunctions of the oscillation modes. The intrinsic couplings of modes through their eigenfunctions can be described by coupling coefficients. Here, we concentrate on quadratic and cubic coupling coefficients that describe the nonlinear coupling of modes with itself and are called self-coupling coefficients.We considered radial and nonradial oscillation modes of polytropic models with degrees of central condensation that correspond to central condensations of main sequence stars to highly condensed evolved stars. We study the influence of the radial order and the degree of the oscillation mode on the self- coupling coefficients.

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Validity of Kinect for Assessment of Joint Motion during Gait

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.660.921 ◽

2014 ◽

Vol 660 ◽

pp. 921-926

Author(s):

Muhammad Rijal Abdurrahman ◽

Tatacipta Dirgantara ◽

Sandro Mihradi ◽

Andi Isra Mahyuddin

Keyword(s):

Gait Analysis ◽

Optical Measurement ◽

High Mobility ◽

Microsoft Kinect ◽

Joint Motion ◽

Camera System ◽

Gait Parameters ◽

Walking Motion ◽

Measurement Tools ◽

3D Camera

One of the most common methods employed in gait analysis is the optical measurement method. While many analyzer systems are available commercially, the prices of those systems are rather prohibitive. In this work, an alternative method to obtain gait data using Microsoft KinectTM(Kinect) is investigated. Kinect, a 3D camera system created for gaming purposes, offers an ability which may be suitable for application in gait analysis. It has high mobility, needs no marker, is easy to use, and its price is relatively affordable. However, the performance of Kinect as a measurement tools in gait analysis must be first evaluated. In this work, Kinect is utilized to obtain joint movements of human walking motion to evaluate its suitability as an alternative motion analyzer in gait analyses. The data generated by Kinect are then processed to obtain gait parameters. The resulting parameters are compared to those obtained by 3D Motion Analyzer System that uses multi-camera previously developed. The results show promising prospect for Kinect application in gait analysis.

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Numerical Validation of the Ethanol Spray Produced by a Direct Injection Injector for Different Pressure Conditions

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.798.213 ◽

2015 ◽

Vol 798 ◽

pp. 213-218

Author(s):

Felipe Grossi L. Amorim ◽

Marcio E. Guzzo ◽

Leonardo Mayer Reis ◽

R.O. Coelho ◽

Ramon Molina Valle

Keyword(s):

Numerical Model ◽

Internal Combustion Engines ◽

Dynamic Models ◽

Fuel Injection ◽

Optical Measurement ◽

Penetration Rate ◽

Direct Injection ◽

Combustion Engines ◽

Physical Test ◽

Measurement Tools

This study presents a methodology to validate CFD simulations of the spray fuel injection using an experimental bench and optical measurement tools along with the Shadowgraph Technique. The parameter used for validating the experiments is the penetration rate, under situations of 6 bar and 100 bar injection pressures. The results show a penetration rate difference lower than 3% between the numerical model and the physical test. The visual plots, considering the shape and angles of the spray, also matched. Once validated, the numerical model could be applied to dynamic models of internal combustion engines and used to elaborate injection strategies for future projects.

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