Anna Firych-Nowacka, Krzysztof Smolka and Sławomir Wiak
Electrospinning is a method of the polymer super thin fibres formation by the electrostatic field. The distribution of electrostatic field affects the effectiveness of the…
Abstract
Purpose
Electrospinning is a method of the polymer super thin fibres formation by the electrostatic field. The distribution of electrostatic field affects the effectiveness of the electrospinning.
Design/methodology/approach
This paper presents various computer models that can improve the electrospinning process. The possibilities of modelling the electrostatic field in the design of electrospinning equipment are presented.
Findings
In the research part, the one focussed on finding a cylinder-shaped collector structure to limit the adverse effect of an uneven distribution of the electric field intensity on the collector.
Originality/value
The paper concerns the improvement of the electrospinning process with the use of electrostatic field modelling. In the first part, several possible applications of electrostatic models have been indicated, thanks to which the efficiency of the process has been improved. The original solution of the collector geometry was presented, which according to the authors, in comparison with previous models, gives the most promising results. In this solution, it was possible to obtain an even distribution of the electric field intensity while removing the unfavourable effect of the field strength increase on the outer edges of the collector. The most important aspect in this paper is electric field strength analysis.
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Slawomir Wiak and Krzysztof Smółka
This paper aims to focus on the hybrid numerical method for effective design of silicon micromotor.
Abstract
Purpose
This paper aims to focus on the hybrid numerical method for effective design of silicon micromotor.
Design/methodology/approach
In this work, the authors introduced finite element methods combined with LUA and Matlab. The paper focuses on analysis of electrostatic micromotor and uses computer simulation procedure leading to new structure design.
Findings
This strategy enables changing of all parameters of the micromotors MEMS. Moreover, this strategy allows for taking advantage of FEM, namely possibility of calculations of complicated geometries (different electromagnetic devices too) without additional operations.
Originality/value
A novel strategy in computer modeling of micromotor MEMS, based on the fast and very efficient hybrid method for analysis and design, is proposed.
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Andrzej J Nowak, Michal Palacz, Jacek Smolka, Krzysztof Banasiak, Zbigniew Bulinski, Adam Fic and Armin Hafner
The purpose of this paper is to overview successful approaches to the computational simulation of real fluid (R744 – carbon dioxide (CO2)) flow within an ejector is presented…
Abstract
Purpose
The purpose of this paper is to overview successful approaches to the computational simulation of real fluid (R744 – carbon dioxide (CO2)) flow within an ejector is presented. Important issues such as the ejector geometry and its optimisation, the adapted equations of state and the proposed models of the process, fluid parameters, etc., are examined and critically discussed. Whenever possible, the discussed models are experimentally validated. In the conclusion, some trends in future research are pointed out.
Design/methodology/approach
Flow within CO2 ejector is generally transcritical and compressible. Models existing in the literature are shortly described and critically compared. Whenever possible, those models were validated against the experimental data. In a model validation process, the primary and secondary mass flow rates as well as the pressures at the selected points in the mixing section and diffuser were compared, showing a satisfactory agreement between experimental and computational results.
Findings
Developed CO2 ejector flow models are tested in few industrial applications. All these initiatives bring solutions which are interesting and very promising from technological point of view.
Originality/value
This is an extensive overview of successful approaches to computational simulation of the real fluid (R744 – CO2) flow within ejector. It brings many useful information.
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Sławomir Wiak, Anna Firych‐Nowacka and Krzysztof Smółka
The purpose of this paper is to discuss the idea of designing and manufacturing intelligent clothes with magnetic fibres. The main goal of the research is to create the universal…
Abstract
Purpose
The purpose of this paper is to discuss the idea of designing and manufacturing intelligent clothes with magnetic fibres. The main goal of the research is to create the universal generator of computer structural models for whole bundles of magnetic microfibres.
Design/methodology/approach
The paper presents the algorithm of magnetic microfibers computer modelling. It covers both finite element method (FEM) and reluctance network method. This paper deals with creating 3D computer structural models of magnetic microfibres, which could be introduced as the textile magnetic sensors or actuators. Because of very complicated 3D microfibres structure, it is hoped that the quickest possible method can be found to solve the problem.
Findings
The results focus on the methodology presented in the paper which can be implemented in building 3D equivalent B/H curve of the microfibers set by using the field method – combining reluctance network method and FEM. Defining the proper magnetic B/H curves of magnetic fibres will enable the production of smart and resistant clothes.
Originality/value
First, the paper presents the original idea of modelling magnetic microfibres by use of the reluctance network method. So far, there are only measurements characteristics of B/H curve of magnetic microfibres. The paper proposes an innovatory way of determining magnetic microfibres parameters. This universal computer models allows for evaluation of a limiting value of magnetization (magnetic permeability, etc.).
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Sławomir Wiak, Anna Firych‐Nowacka and Krzysztof Smółka
The purpose of this paper is to describe research into the problem of creating computer structural models of magnetic microfibres. The main goal of the research is to create the…
Abstract
Purpose
The purpose of this paper is to describe research into the problem of creating computer structural models of magnetic microfibres. The main goal of the research is to create the universal generator of computer structural models for whole bundles of magnetic microfibres.
Design/methodology/approach
The paper presents the algorithm of magnetic microfibres computer modelling. It covers both finite element method (FEM) and reluctance network method. Because microfibres with ferromagnetic grains have very complicated 3D structure, the quickest possible method was chosen.
Findings
The results focus on the methodology presented in the paper which can be implemented in building 3D equivalent B/H curve of the microfibres set by use of field method – combining reluctance network method and FEM. Defining the proper magnetic B/H curves of magnetic fibres will enable the production of smart and resistant clothes.
Originality/value
To date there are only measurements characteristics of B/H curve of magnetic microfibres. This paper proposes an innovatory way of determining magnetic microfibres parameters. This universal computer model allows the evaluation of the limiting value of magnetization (magnetic permeability, etc.).