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Article
Publication date: 2 January 2018

Dmytro Svyetlichnyy, Michal Krzyzanowski, Robert Straka, Lukasz Lach and W. Mark Rainforth

The holistic numerical model based on cellular automata (CA) and lattice Boltzmann method (LBM) are being developed as part of an integrated modelling approach applied to…

Abstract

Purpose

The holistic numerical model based on cellular automata (CA) and lattice Boltzmann method (LBM) are being developed as part of an integrated modelling approach applied to study the interaction of different physical mechanisms in laser-assisted additive layer manufacturing (ALM) of orthopaedic implants. Several physical events occurring in sequence or simultaneously are considered in the holistic model. They include a powder bed deposition, laser energy absorption and heating of the powder bed by the moving laser beam, leading to powder melting or sintering, fluid flow in the melted pool and flow through partly or not melted material, and solidification. The purpose of this study is to develop a structure of the holistic numerical model based on CA and LBM applicable for studying the interaction of the different physical mechanisms in ALM of orthopaedic implants. The model supposed to be compatible with the earlier developed CA-based model for the generation of the powder bed.

Design/methodology/approach

The mentioned physical events are accompanied by heat transfer in solid and liquid phases including interface heat transfer at the boundaries. The sintering/melting model is being developed using LBM as an independent numerical method for hydrodynamic simulations originated from lattice gas cellular automata. It is going to be coupled with the CA-based model of powder bed generation.

Findings

The entire laser-assisted ALM process has been analysed and divided on several stages considering the relevant physical phenomena. The entire holistic model consisting of four interrelated submodels has currently been developed to a different extent. The submodels include the CA-based model of powder bed generation, the LBM-CA-based model of heat exchange and transfer, the thermal solid-liquid interface model and the mechanical solid-liquid interface model for continuous liquid flow.

Practical implications

The results obtained can be used to explain the interaction of the different physical mechanisms in ALM, which is an intensively developing field of advanced manufacturing of metal, non-metal and composite structural parts, for instance, in bio-engineering. The proposed holistic model is considered to be a part of the integrated modelling approach being developed as a numerical tool for investigation of the co-operative relationships between multiphysical phenomena occurring in sequence or simultaneously during heating of the powder bed by the moving high energy heat source, leading to selective powder sintering or melting, fluid flow in the melted pool and through partly (or not) melted material, as well as solidification. The model is compatible with the earlier developed CA-based model for the generation of the powder bed, allowing for decrease in the numerical noise.

Originality/value

The present results are original and new for the study of the complex relationships between multiphysical phenomena occurring during ALM process based on selective laser sintering or melting, including fluid flow and heat transfer, identified as crucial for obtaining the desirable properties.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 6 February 2017

Bartlomiej Guzowski, Roman Gozdur, Mateusz Lakomski and Lukasz Bernacki

The purpose of this paper is to develop identification system for fiber optic connectors in passive distribution cabinets. The system should have alternative power supply…

Abstract

Purpose

The purpose of this paper is to develop identification system for fiber optic connectors in passive distribution cabinets. The system should have alternative power supply and wireless communication unlike the identification systems commercially available, which will make the system fully autonomous.

Design/methodology/approach

Detailed project and realization of real demonstrator of fully autonomous identification system. After the realization of the demonstrator, its optimization was performed.

Findings

It is possible to build fully autonomous identification system which requires 15.6 mJ energy to perform one cycle of identification process. Moreover, it is possible to use the alternative power method to supply this system.

Originality/value

Fully autonomous identification system of fiber optic connectors with alternative power supply and wireless communication.

Details

Circuit World, vol. 43 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

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