A Numerical Model with arc length variation of welding arc with constant voltage power source

Abstract Robotic Wire Arc Additive Manufacturing (WAAM) is the layer-by-layer deposition of molten metal to build a three-dimensional part. In this process, the fed metal wire is melted using an electric arc as a heat source. The process is sensitive to the arc conditions, such as arc length. While building WAAM parts, the metal beads overlap at corners causing material accumulation. Material accumulation is undesirable as it leads to uneven build height and process failures caused by arc length variation. This paper introduces a deposition speed regulation scheme to avoid the corner accumulation problem and build parts with uniform build height. The regulated speed has a complex relationship with the corner angle, bead geometry, and molten metal dynamics. So we need to train a model that can predict suitable speed regulations for corner angles encountered while building the part. We develop an unsupervised learning technique to characterize the uniformity of the bead profile of a WAAM built layer and check for anomalous bead profiles. We train a model using these results that can predict suitable speed regulation parameters for different corner angles. We test this model by building a WAAM part using our speed regulation scheme and validate if the built part has uniform build height and reduced corner defects.

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The arc-length variation of analytic capacity and a conformal geometry

Nagoya Mathematical Journal ◽

10.1017/s0027763000003950 ◽

1992 ◽

Vol 125 ◽

pp. 151-216

Author(s):

Takafumi Murai

Keyword(s):

Banach Space ◽

Complex Plane ◽

Analytic Functions ◽

Conformal Geometry ◽

Supremum Norm ◽

Length Variation ◽

Analytic Capacity ◽

Arc Length ◽

Bounded Analytic Functions ◽

Extended Complex

For a domain Ω in the extended complex plane C ∪{∞}, H∞(Ω) denotes the Banach space of bounded analytic functions in Ω with supremum norm ∥ · ∥H∞ For ζ ∈ Ω, we putwhere f′(∞) = lim,z→∞z{f (∞) = f(z)} if ζ = ∞.

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Development of a New Bi-Arc Dynamic Numerical Model for Modeling AC Flashover Processes of EHV Ice-Covered Insulators

Energies ◽

10.3390/en11102792 ◽

2018 ◽

Vol 11 (10) ◽

pp. 2792

Author(s):

Marouane Jabbari ◽

Christophe Volat ◽

Issouf Fofana

Keyword(s):

Numerical Model ◽

High Accuracy ◽

Arc Length ◽

Calculation Algorithm ◽

Water Conductivity ◽

Arc Model ◽

Proposed Model ◽

Flashover Voltage ◽

Extra High Voltage ◽

Future Work

This paper presents the development of a new bi-arc dynamic numerical model for predicting AC critical flashover voltage (FOV) of ice-covered extra-high voltage (EHV) insulators. The proposed model is based on a generic calculation algorithm coupled with commercial finite element method software designed to solve the Obenaus/Rizk model. The proposed model allows one to implement the Nottingham and Mayr approaches and compare the results obtained as a function of the arcing distance, the freezing water conductivity, and the initial arc length. The validation of the model demonstrated high accuracy in predicting the FOV of ice-covered post-type insulators and its capability to simulate the interaction of the two partial arcs during the flashover process. In particular, the results showed that the Nottingham approach is sensibly more accurate than the Mayr one, especially in simulating the dynamic behavior of the partial arcs during the flashover process. Based on the encouraging results obtained, a multi-arc calculation algorithm was proposed using the bi-arc dynamic numerical model as a basis. The basic idea, which consists in dividing the multi-arc model in several bi-arc modules, was not implemented and validated but will serve as a promising concept for future work.

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Energy characteristics of the power source‐welding arc system

Welding International ◽

10.1080/09507110209549645 ◽

2002 ◽

Vol 16 (12) ◽

pp. 966-969 ◽

Cited By ~ 2

Author(s):

A V Agunov ◽

M V Agunov ◽

G M Korotkova ◽

V I Stolbov ◽

A A Shevtsov

Keyword(s):

Power Source ◽

Energy Characteristics ◽

Welding Arc

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The Behaviour of Nitrogen on the Welding Parameters of the Dissimilar Weld Joints between AISI 304 and AISI 316L Austenitic Stainless Steels Produced by Gas Tungsten Arc Welding

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.248.395 ◽

2012 ◽

Vol 248 ◽

pp. 395-401 ◽

Cited By ~ 2

Author(s):

Wichan Chuaiphan ◽

Loeshpahn Srijaroenpramong

Keyword(s):

Weld Metal ◽

Nitrogen Content ◽

Welding Current ◽

Welding Parameters ◽

Aisi 316L ◽

Arc Length ◽

Aisi 304 ◽

Dissimilar Weld ◽

Weld Metals ◽

Welding Arc

The behavior of nitrogen into the dissimilar joining metal between AISI 304 and AISI 316L Austenitic stainless steel during gas tungsten are welding process was investigated. Studied by using an arc nitrogen atmosphere – controlling in chamber. The relations between nitrogen content of the dissimilar weld metal and the welding parameters, such as the welding current, welding speed, welding arc length and penetration area of weld metals were also evaluated. The results show that the nitrogen content of the weld metals decreased with an increasing welding current, and increasing penetration areas of weld metal, but scarcely depends on the welding arc length. The nitrogen content of the weld metals increased with the welding speed, but decreased penetration areas of weld metals. The role of nitrogen content on the dissimilar weld metals stainless steel is further confirmed by the experimental microstructure, mechanical and corrosion behaviour of the weld metal.

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Pulse MIG welding of aluminium using constant voltage characteristic power source

Welding International ◽

10.1080/09507110209549514 ◽

2002 ◽

Vol 16 (3) ◽

pp. 173-182 ◽

Cited By ~ 1

Author(s):

T Mita

Keyword(s):

Power Source ◽

Voltage Characteristic ◽

Constant Voltage ◽

Mig Welding

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The Design of Current Carrying Mechanisms Operating in a Magnetic Field

Journal of Mechanical Design ◽

10.1115/1.3453970 ◽

1978 ◽

Vol 100 (3) ◽

pp. 574-582

Author(s):

W. S. Reed ◽

W. D. Smith

Keyword(s):

Magnetic Field ◽

Numerical Model ◽

Angular Velocity ◽

Experimental Work ◽

Equations Of Motion ◽

Constant Angular Velocity ◽

Constant Voltage ◽

Constant Torque ◽

Parametric Studies ◽

Velocity Input

Extensions to earlier work presented on the electrodynamics of a planar mechanism moving in a magnetic field are considered in this paper. The effects of damping and self-fields are added to the equations of motion. These equations are then integrated numerically for an example design having a constant torque input, a constant angular velocity input, and a constant voltage input. The results of numerous parametric studies are then presented as a basis for design of these devices. Finally the results of experimental work are presented in order to verify the numerical model.

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Design and Fabrication of MEMS-Based Solid Propellant Microthrusters Array

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.490-491.1042 ◽

2014 ◽

Vol 490-491 ◽

pp. 1042-1046 ◽

Cited By ~ 7

Author(s):

Cheng Bo Ru ◽

Ying Hua Ye ◽

Cheng Ling Wang ◽

Peng Zhu ◽

Rui Qi Shen ◽

...

Keyword(s):

Solid Propellant ◽

High Speed ◽

Adhesive Bonding ◽

Power Source ◽

Test Stand ◽

Propulsion System ◽

Constant Voltage ◽

Initial Test ◽

Video System ◽

High Speed Video

A solid propellant microthruster array consists of three parts (five layers) was designed to form propulsion system of nanosatellite. The layers of the array were fabricated by different MEMS technique respectively. Then the array was assembled by adhesive bonding (H70E thermal epoxy). An initial test was operated with the ignition test stand composed of high speed video system, electronic power source, and oscilloscope. A constant voltage was applied to the igniters through two probes contact with the pad of ignition circuitry. The test indicates that the microthruster array can be ignited under 15V.

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