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Article
Publication date: 7 February 2024

Andrzej Wojciech Nowak

This study aims to demonstrate what myths of and about science are reproduced in this popular cultural work (movie – “Oppenheimer”). This is done by examining the unconscious…

Abstract

Purpose

This study aims to demonstrate what myths of and about science are reproduced in this popular cultural work (movie – “Oppenheimer”). This is done by examining the unconscious hegemonic positions supported by the reproduction of stereotypical and mythical images of science.

Design/methodology/approach

Content/Text Analysis: The conceptual analysis of a cultural text – a film (“Oppenheimer”) – through a theoretical apparatus (B. Latour’s theory).

Findings

The film demonstrates its reproduction of three distinct elements. Firstly, it exhibits classic scientistic clichés pertaining to technoscience. Secondly, it highlights the replication of the individualized monomyth about the (super) hero, leading to the exclusion of the intricate conditions of technoscience’s existence. Lastly, the film aligns with the Californian ideology, as proposed by Barbrook.

Originality/value

The value of the text is twofold: (1) To show that the classical approaches of Bruno Latour are still relevant. (2) To show what hidden premises and myths about technoscience are being propagated through a work of pop culture (the film “Oppenheimer”) and, in effect, to show what kind of influence of cultural hegemony is at work here.

Details

Qualitative Research in Organizations and Management: An International Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1746-5648

Keywords

Article
Publication date: 29 April 2014

Wojciech P. Adamczyk, Pawel Kozolub, Gabriel Węcel and Arkadiusz Ryfa

The purpose of this paper is to show possible approaches which can be used for modeling complex flow phenomena caused by swirl burners combined with simulating coal combustion…

Abstract

Purpose

The purpose of this paper is to show possible approaches which can be used for modeling complex flow phenomena caused by swirl burners combined with simulating coal combustion process using air- and oxy-combustion technologies. Additionally, the response of exist boiler working parameter on changing the oxidizer composition from air to a mixture of the oxygen and recirculated flue gases is investigated. Moreover, the heat transfer in the superheaters section of the boiler was taken into account by modeling of the heat exchange process between continuum phase and three stages of the steam superheaters.

Design/methodology/approach

An accurate solution of the flow field is required in order to predict combustion phenomena correctly for numerical simulations of the industrial pulverized coal (PC) boilers. Nevertheless, it is a very demanding task due to the complicated swirl burner construction and complex character of the flow. The presented simulations were performed using the discrete phase model for tracking particles and combustion phenomena in a dispersed phase, whereas the Eulerian approach was applied for the volatile combustion process modeling in a gaseous phase.

Findings

Applying the air- to oxy-combustion technology the temperature in the combustion chamber, decreased for investigated oxidizer compositions. This was caused by the higher heat capacity of flue gases which also influences on the level of the heat flux at the boiler walls. Simulations shows that increasing the O2 concentration to 30 percent of volume base in the oxidizer mixture provided the similar combustion conditions as those for the conventional air firing. Moreover, the evaluated results give a good overview of differences between approaches used for complex swirl burners simulations.

Practical implications

Nowadays, the numerical techniques such as computational fluid dynamic (CFD) can be seen as an useful engineering tool for design and processes optimization purposes. The application of the CFD gives a possibility to predict the combustion phenomena in a large industrial PC boiler and investigate the impact of changing the combustion technology from a conventional air firing to oxy-fuel combustion.

Originality/value

This paper gives good overview on existing technique, approaches used for modeling PC boiler equipped with complex swirl burners. Additionally, the novelty of this work is application of the heat exchanger model for predicting heat loses in convective section of the boiler. This usually is not taken into account during simulations. The reader can also find basic concept of oxy-combustion technology, and their impact on boiler working conditions.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 24 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 7 November 2019

Bartlomiej Melka, Wojciech P. Adamczyk, Marek Rojczyk, Marcin L. Nowak, Maria Gracka, Andrzej J. Nowak, Adam Golda, Ryszard A. Bialecki and Ziemowit Ostrowski

The purpose of this paper is the application of the computational fluid dynamics model simulating the blood flow within the aorta of an eight-year-old patient with Coarctation of…

Abstract

Purpose

The purpose of this paper is the application of the computational fluid dynamics model simulating the blood flow within the aorta of an eight-year-old patient with Coarctation of Aorta.

Design/methodology/approach

The numerical model, based on commercial code ANSYS Fluent, was built using the multifluid Euler–Euler approach with the interaction between the phases described by the kinetic theory of granular flow (KTGF).

Findings

A model of the blood flow in the arches of the main aorta branches has been presented. The model was built using the multifluid Euler–Euler approach with the interaction between the phases described by the KTGF. The flow and pressure patterns, as well as the volumetric concentration of the blood components, were calculated. The lumped parameter model was implemented to couple the interaction of the computational domain with the remaining portion of the vascular bed.

Originality/value

The multiphase model based on the Euler–Euler approach describing blood flow in the branched large vessel with a three-element Windkessel model in the coarcted geometry was not previously described in the literature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 April 1995

Wojciech Szelag, Andrzej Demenko and Lech Nowak

The time‐stepping finite method of transient analysis in permanent magnet synchronous machines has been presented. This method has been used for determining the steady‐state and…

Abstract

The time‐stepping finite method of transient analysis in permanent magnet synchronous machines has been presented. This method has been used for determining the steady‐state and dynamic performance of the permanent magnet self‐starting synchronous motor. The movement of the rotor, the saturation of the ferromagnetic core, the properties of permanent magnet and eddy currents in the solid bars of the cage winding have been taken into account.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 14 no. 4
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 10 May 2011

Mariusz Baranski, Andrzej Demenko, Wieslaw Lyskawinski and Wojciech Szelag

The purpose of this paper is to elaborate the method and algorithm for the analysis of electromagnetic and thermal transients in a squirrel cage induction motor.

Abstract

Purpose

The purpose of this paper is to elaborate the method and algorithm for the analysis of electromagnetic and thermal transients in a squirrel cage induction motor.

Design/methodology/approach

The paper presents the special software for transient finite element (FE) analysis of coupled electromagnetic‐thermal problems in a squirrel cage induction motor. The software has been prepared and is successfully applied in the design of special squirrel cage motors, e.g. the motors working in cryogenic conditions. A time‐stepping FE method and transients analysis of an induction motor has been applied. The nonlinearity of the magnetic circuit, the movement of the rotor and the skewed slots have been taken into account. The results of computations have been compared with measurements.

Findings

The method presented and the elaborated specialised software for FE analysis of electromagnetic and thermal transients are used to determine the dynamic performance of the squirrel‐cage induction motor. The results of simulations compared with measurements confirm the adequacy of this approach to the analysis of coupled electromagnetic‐thermal problems.

Research limitations/implications

3D effects have only been taken into account by quasi‐3D techniques (e.g. the multi‐slice for the skewed rotor slots).

Practical implications

The software developed can be useful in the analysis and design of squirrel cage motor, especially motors working in cryogenic conditions.

Originality/value

The paper offers appropriate software for transient analysis of coupled electromagnetic and thermal problems in squirrel cage motors with skewed slots.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 30 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 29 April 2014

Joanna Łaszczyk, Anna Maczko, Wojciech Walas and Andrzej J. Nowak

This paper aims to test the inverse analysis, based on the standard least-square method, which will finally lead to find the appropriate parameters of modelling of the brain…

Abstract

Purpose

This paper aims to test the inverse analysis, based on the standard least-square method, which will finally lead to find the appropriate parameters of modelling of the brain cooling process.

Design/methodology/approach

To test the presented in this paper method of inverse analysis the numerical simulations of the bioheat transfer process in the neonatal body were performed. To model the bioheat transfer the Pennes bioheat equation and the modified Fiala model were applied.

Findings

The performed tests of the inverse analysis proved that it is possible to estimate the proper parameters of the process using this tool, but always with the small mistake.

Research limitations/implications

The presented method still requires a lot of tests. The test with the data from real measurements can be very valuable.

Practical implications

The determination of the proper parameters of the bioheat transfer in the neonatal body can finally be used to perform the numerical simulations of the brain cooling process.

Social implications

The performance of the numerical simulations of the brain cooling process in the proper way can finally helps protect newborns’ health and life.

Originality/value

In the paper the attempt of the inverse analysis in order to determine the parameters of bioheat transfer in the newborn's body is made.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 24 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Content available
Article
Publication date: 10 May 2011

Andrzej Demenko, Kay Hameyer, Stefan Kulig, Lech Nowak, Krzysztof Zawirski and Wojciech Pietrowski

341

Abstract

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 30 no. 3
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 1 December 2004

Lech Nowak, Andrzej Demenko and Wojciech Szeląg

This paper deals with a coupled field‐circuit simulation of transients in a three‐phase, three‐limb power transformer taking non‐linearity into consideration. A comparative…

Abstract

This paper deals with a coupled field‐circuit simulation of transients in a three‐phase, three‐limb power transformer taking non‐linearity into consideration. A comparative analysis of the results obtained from the application of 3D and 2D field models has been carried out. Owing to core saturation and the non‐periodic components of the magnetic fluxes, the magnetic field exists also within the space surrounding the core. Hence, three‐dimensional description is necessary. It has been proved that assuming the 2D model significantly overstated peak values of currents are obtained.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 23 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 14 August 2007

Jerzy Kołowrotkiewicz, Mariusz Barański, Wojciech Szelęg and Lech Długiewicz

The paper aims to elaborate the method and algorithm of analysis of induction motor working in cryogenic temperature.

Abstract

Purpose

The paper aims to elaborate the method and algorithm of analysis of induction motor working in cryogenic temperature.

Design/methodology/approach

This paper presents the design and investigation of performance characteristics of three‐phase high voltage squirrel‐cage submerged motor. The motor is intended to work at cryogenic temperature −161°C in liquefied natural gas (LNG). The time‐stepping finite element method of transients analysis in induction motor working in cryogenic temperature has been presented. The nonlinearity of the magnetic circuit, the movement of the rotor and skewed slots have been taken into account.

Findings

The study finds that presented method and elaborated software are used to determine the steady state and dynamic performance of the high voltage squirrel‐cage submerged motor. The results of simulations and measurements of constructed model motor have been presented.

Research limitations/implications

The problem has been considered as the 2D one. In order to take into account the skewed slots of the rotor the multi‐slice finite element method has been used.

Practical implications

Investigation presented in the paper has been performed in order to study the influence of the temperature on motor characteristics and to verify design calculations. No‐load current, starting torque and short‐circuit current during short‐circuit test, obtained on the basis of measurements and received from calculations, are in good concordance.

Originality/value

The paper proposes a method to determine the steady state and dynamic performance of the high voltage squirrel‐cage submerged motor working in cryogenic temperature.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 26 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 January 2006

Andrzej Demenko, Ernest Mendrela and Wojciech Szeląg

The aim of the paper is to find the simple and accurate model for the analysis of a drive with a tubular linear permanent magnet machine (TLPMM). Attention is paid to the models…

Abstract

Purpose

The aim of the paper is to find the simple and accurate model for the analysis of a drive with a tubular linear permanent magnet machine (TLPMM). Attention is paid to the models that take into account the saturation effects and is useful in the calculations of electromagnetic forces.

Design/methodology/approach

A circuit model and a field‐circuit model (FCM) are considered. The FCM includes finite element (FE) formulation for the axisymmetric electromagnetic field, equations which define the connections of windings and converter elements, and expressions that describe the control system. The FE method is used to determine the parameters of the circuit model. In order to simplify the circuit model, saturation effects caused by armature reaction are ignored. The electromagnetic force calculation is based on the virtual work principle and uses an approximate expression for the derivative of system co‐energy. The results obtained for the proposed models have been compared.

Findings

The proposed FE method of force calculation conforms with the applied method of movement simulation. For the rotor position when the cogging force is equal to zero the calculated cogging force is “almost” zero within seven‐decimal‐place accuracy. The effects of armature reaction on the performance of a TLPMM machine are similar to those which occur in a classical DC machine; in particular the demagnetising effect caused by saturation is observed.

Originality/value

The paper shows the influence of the saturation effects on the electromagnetic force of a TLPMM. In the case of “strong saturation”, the classical circuit model may be inappropriate for engineering calculations.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 25 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

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