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Article
Publication date: 16 November 2021

Krzysztof Posobkiewicz and Krzysztof Górecki

The purpose of this study is to investigate the validation of the usefulness of cooling systems containing Peltier modules for cooling power devices based on measurements…

Abstract

Purpose

The purpose of this study is to investigate the validation of the usefulness of cooling systems containing Peltier modules for cooling power devices based on measurements of the influence of selected factors on the value of thermal resistance of such a cooling system.

Design/methodology/approach

A cooling system containing a heat-sink, a Peltier module and a fan was built by the authors and the measurements of temperatures and thermal resistance in various supply conditions of the Peltier module and the fan were carried out and discussed.

Findings

Conclusions from the research carried out answer the question if the use of Peltier modules in active cooling systems provides any benefits comparing with cooling systems containing just passive heat-sinks or conventional active heat-sinks constructed of a heat-sink and a fan.

Research limitations/implications

The research carried out is the preliminary stage to asses if a compact thermal model of the investigated cooling system can be formulated.

Originality/value

In the paper, the original results of measurements and calculations of parameters of a cooling system containing a Peltier module and an active heat-sink are presented and discussed. An influence of power dissipated in the components of the cooling system on its efficiency is investigated.

Details

Microelectronics International, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 1 February 2002

J.E. Ruckman, S.G. Hayes and J.H. Cho

Based upon numerous assertions that a garment should be developed to maximise athletes' muscle performance while maintaining freedom of movement, this paper initially…

Abstract

Based upon numerous assertions that a garment should be developed to maximise athletes' muscle performance while maintaining freedom of movement, this paper initially discusses the development of a perfusion suit that utilises a flexible single layer cooling system, with a view to the development of a cooling garment that does not employ a conventional tubing system which can restrict movement. The stages of the development have been described in detail, and an appropriate evaluation completed for both the initially developed perfusion suit and the subsequently developed cooling garment (modified perfusion suit). From results obtained from experiments conducted using the cooling garment, which incorporates super absorbent sodium polyacrylate pads as the cooling component, the following conclusions were drawn. First, anterior thigh temperature was reduced by 4–5°C at the end of the cooling period confirming that the developed cooling garment provides effective cooling. Second, although the difference between the skin temperature of the anterior thigh when cooling is applied to that when cooling is not applied decreased during the exercise period, the difference is still significant confirming that cooling of the anterior thigh by wearing the developed cooling garment persists throughout the duration of exercise.

Details

International Journal of Clothing Science and Technology, vol. 14 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 3 October 2008

Kai Yang, Ming‐Li Jiao, Yi‐Song Chen, Jun Li and Wei‐Yuan Zhang

The purpose of this paper is to explore the heat transfer and establish a heat transfer model of an extravehicular liquid cooling garment based on a thermal manikin…

Abstract

Purpose

The purpose of this paper is to explore the heat transfer and establish a heat transfer model of an extravehicular liquid cooling garment based on a thermal manikin covered with soft simulated skin.

Design/methodology/approach

The thermal manikin applied in this study was a copper manikin, typical of which was its soft simulated skin – a newly thermoplastic elastomer material. Based on this novel thermal manikin, the heat transfer analysis of an extravehicular liquid cooling garment was performed. To satisfy the practical engineering application and simplify analysis, the hypotheses were proposed, and then the heat transfer model was established by heat transfer theory, in which the heat exchange equation of the liquid cooling garment with the thermal manikin and with the air layer, and the garment's total heat dissipating capacity were derived.

Findings

The verification experiments performed in a climatic chamber by a thermal manikin wearing a liquid cooling garment at different surface temperatures of the thermal manikin show that the modeling value fits well with the experimental value, and the heat transfer model of the liquid cooling garment has a high accuracy. Meanwhile, the relationship between the heat‐dissipating capacity of the liquid cooling garment and its design parameters – inlet temperature and liquid velocity – is suggested as being based on the heat transfer model.

Originality/value

The paper shows that it is an effective method to control the heat‐dissipating capacity of a liquid cooling garment by changing the inlet temperature to some degree, but not by changing the liquid velocity.

Details

International Journal of Clothing Science and Technology, vol. 20 no. 5
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 7 June 2013

Khurram Altaf, Ahmad Majdi Abdul Rani and Vijay R. Raghavan

The purpose of this paper is to present a technique of fabricating profiled conformal cooling channels (PCCC) in an aluminium filled epoxy mould using rapid prototyping…

1033

Abstract

Purpose

The purpose of this paper is to present a technique of fabricating profiled conformal cooling channels (PCCC) in an aluminium filled epoxy mould using rapid prototyping (RP) and rapid tooling (RT) techniques and to compare the cooling times for the moulds with circular and profiled channels experimentally. The cooling channels in injection mould tools have a circular cross section. In a PCCC, the cross sectional shape is so designed that the flat face surface of the channel facing the cavity follows the profile of the cavity. These types of channels can be manufactured through RP and RT techniques.

Design/methodology/approach

A part to be moulded was designed and modelled. Two moulds were then designed with the part cavity, one having a circular channel and the second with a profiled channel, both having the same cross sectional area for coolant flow. The channel patterns were designed with supports according to their position regarding height and distance from the cavity as designed earlier. Both channels have the same distance from the cavity wall. RP patterns were produced for both channels and part using the Thermojet 3D printer. The cooling channel and the moulded part patterns were then assembled as designed in the moulds. Moulding frames were fabricated with aluminium plates and the pattern was placed in the frames. Epoxy was poured on the pattern and then cured. The moulded part and the channel patterns embedded inside epoxy were melted out during the final curing cycle, leaving behind the circular‐ and profiled‐cooling channels in the moulds. For the cooling time measurement, injection moulding was done with moulds with circular and profiled channels. Moulded part temperature will be recorded by embedding thermocouples within the mould cavities.

Findings

A technique for the manufacture of cooling channels of different profiles in epoxy moulds was presented. Experimental analysis for temperature measurement for the moulded part with injection moulding process showed that PCCC mould has less cooling time then mould with circular channels.

Research limitations/implications

The technique presented is based on the metal‐filled epoxy materials used in RT and was obtained using a specific test part. Epoxy tooling can be a useful alternative of metallic mould to produce injection mould tools. A limitation for the epoxy moulds is that they have a limited life as compared with metallic moulds.

Originality/value

This is a new technique of manufacturing moulds with cooling channels using RP/RT techniques. Moulds with different channel cross sections can be manufactured using this technique.

Article
Publication date: 17 May 2011

Sheng‐hong Chen, Peifang Su and Isam Shahrour

Pipe cooling is an important measure for controlling the temperature in mass concrete. Since the temperature field in mass concrete containing cooling pipes is unsteady…

Abstract

Purpose

Pipe cooling is an important measure for controlling the temperature in mass concrete. Since the temperature field in mass concrete containing cooling pipes is unsteady and three‐dimensional, and there are huge quantities of the cooling pipes in the concrete, the study of efficient and reliable algorithm is crucial. The purpose of this paper is to develop the composite element method (CEM) for the temperature field in mass concrete containing cooling pipes.

Design/methodology/approach

Each cooling pipe segment is looked at as a special sub‐element having definite thermal characteristics, which is located explicitly within the composite element. By the variational principle, the governing equation for the composite element containing cooling pipes is established.

Findings

One of the remarkable advantages of the method proposed is that each cooling pipe can be simulated explicitly while the difficulty of mesh generation around cooling pipes can be avoided.

Originality/value

The paper demonstrates how composite elements containing cooling pipes are degenerated to the conventional finite elements automatically when the first stage artificial cooling finished, and conversely, the conventional finite elements can also be transformed to the composite elements automatically when the second stage artificial cooling started. The comparison of the numerical example using FEM and CEM shows the rationality of the proposed method.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 21 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 13 February 2017

Muhammad Usman, Qazi Shehzad Ali and Muhammed Bilal

Decreasing sources of fossil fuels has caused an increase in importance of the renewable energy resources and systems that directly utilize renewable energy are even more…

Abstract

Purpose

Decreasing sources of fossil fuels has caused an increase in importance of the renewable energy resources and systems that directly utilize renewable energy are even more important. The purpose of the paper is to compare the most common solar cooling technologies against the most important requirements.

Design/methodology/approach

A multi-criteria decision methodology, analytical hierarchical process, has been used to prioritize these technologies with respect to each other.

Findings

The findings of this study are the priorities of selected solar cooling concepts against performance affecting criteria. The solar vapour adsorption cooling system has been found to be the optimum solar cooling concept with practically the highest performance number compared with the other cooling systems.

Originality/value

This study can be used in the future development of solar cooling technologies to benefit from the best collective features of the specific technologies.

Details

World Journal of Engineering, vol. 14 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 7 August 2017

Tao Yan, Liang Ma, Shuo Zhao and Enlin Yu

This study aims to focus on numerical simulation investigations of phase transformation during cooling of 55SiMnMo steel, which is commonly applied to improve mechanical…

Abstract

Purpose

This study aims to focus on numerical simulation investigations of phase transformation during cooling of 55SiMnMo steel, which is commonly applied to improve mechanical properties.

Design/methodology/approach

A mathematical model based on the finite element method (FEM) and the phase transformation kinetics model has been proposed to predict microstructure changes during continuous cooling of 55SiMnMo steel. This model can be employed to analyze the variation of austenite, special upper bainite and lump-like composite structure with cooling time at different cooling rates.

Finding

According to the continuous cooling experiments, when the cooling rate is lower than 0.1°C/s, the special upper bainite is the only transformation product which decreases with increasing cooling rate; when the cooling rate is above 0.5°C/s, the transformation products include special upper bainite and lump-like composite structure. Meanwhile, the results of continuous cooling experiment verified the correctness of this finite element model.

Originality/value

This model has a great value for proper controlling of the cooling process which can improve the quality of hollow drill steel and increase the service life of the final product.

Details

World Journal of Engineering, vol. 14 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 5 September 2018

Byung-Hyun Shin, Junghyun Park, Jongbae Jeon, Sung-bo Heo and Wonsub Chung

In this study, super duplex stainless steel (SDSS) was heat-treated. The purpose of this study is to assess the effect of the cooling rate after heat treatment on the…

Abstract

Purpose

In this study, super duplex stainless steel (SDSS) was heat-treated. The purpose of this study is to assess the effect of the cooling rate after heat treatment on the pitting corrosion of SDSS.

Design/methodology/approach

The heat treatment from 1,000°C to 1,300°C was applied to SDSS to check the effect of the cooling rate.

Findings

The heat treatment temperature produced a different SDSS microstructure, and the cooling rate led to the growth of austenite. The casted SDSS indicated the presence of heterogeneous austenite, and the precipitation secondary phase under 1.6 per cent precipitated to bare metal. By applying heat treatment and cooling SDSS, its corrosion resistance changes because of the change in the chemical composition. The cooling rate at 5,600 J/s has the highest critical pitting temperature (CPT) at 1,100°C, and the cooling rate at 1.6 J/s has the highest CPT at 1,200°C. Low cooling rate (0.4 J/s) made the secondary phase at all temperature range.

Research limitations/implications

The effect of secondary phase not consider because that is well known to decreasing corrosion resistance.

Practical implications

Solution annealing is taken into account to optimize the corrosion resistance. But that is not consider the cooling rate at each temperature. This study assessed the effect of the cooling rate at each temperature point.

Social implications

Manufacturers need to know the effect of the cooling rate to optimize the corrosion resistance, and this study can be applied in the industrial scene.

Originality/value

SDSS is hard the optimization because SDSS is a dual-phase stainless steel. Corrosion resistance can be optimized by controlling heat treatment temperature and the cooling rate. Anyone not studied the effect of the cooling rate at each temperature. The effect of the cooling rate should be considered to optimize the corrosion resistance.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 12 October 2018

Xiaopeng Li, Brecht Van Hooreweder, Wout Lauwers, Bavo Follon, Ann Witvrouw, Kurt Geebelen and Jean-Pierre Kruth

The cooling process of polymer components fabricated by selective laser sintering (SLS) plays a vital role in determining the crystallinity, density and the resultant…

Abstract

Purpose

The cooling process of polymer components fabricated by selective laser sintering (SLS) plays a vital role in determining the crystallinity, density and the resultant properties of the produced parts. However, the control and optimization of the cooling process remains challenging. The purpose of this paper is to therefore investigate the cooling process of the SLS fabricated polyamide 12 (PA12) components through simulations. This work provides necessary fundamental insights into the possibilities for optimization and control of this cooling process for achieving desired properties.

Design/methodology/approach

The thermal properties of the PA12 powder and SLS fabricated PA12 components including density, specific heat and thermal conductivity were first determined experimentally. Then, the finite element method was used to optimize a container (a cuboid aluminum box where PA12 parts are built by the SLS) geometry in which the SLS parts can cool down in a controlled manner. Also, the cooling parameters required for maximum temperature homogeneity and minimum cooling time were determined.

Findings

Two different approximations in the finite element (FE) model were used and compared. It was found that the approximation which considers powder as a solid medium with porous material properties gives better results as compared to the approximation which treats powder as a collection of air and particles with solid material properties. The results also showed that the geometry of the containers has an important influence on the cooling process of the SLS fabricated PA12 components regarding temperature homogeneity and cooling time required. A container with a small width, long length and high height tends to result in a more homogenous temperature distribution during the cooling process.

Originality/value

Thermal constants of PA12 powder and parts were accurately determined as a starting point for numerical simulations. The FE model developed in this work provides useful and necessary information for the optimization and control of the cooling process of the SLS fabricated PA12 components and can thus be used for ensuring high-quality products with desired component properties.

Details

Rapid Prototyping Journal, vol. 24 no. 7
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 14 July 2022

Mohamed Ouni, Fatih Selimefendigil, Besbes Hatem, Lioua Kolsi and Mohamed Omri

The purpose of this study is to analyze the impacts of combined utilization of multi-jet impinging cooling of nanofluids with magnetic field and porous layer on the cooling

Abstract

Purpose

The purpose of this study is to analyze the impacts of combined utilization of multi-jet impinging cooling of nanofluids with magnetic field and porous layer on the cooling performance, as effective cooling with impinging jets are obtained for various energy systems, including photovoltaic panels, electronic cooling and many other convective heat transfer applications.

Design/methodology/approach

Finite element method is used to explore the magnetic field effects with the inclusion of porous layer on the cooling performance efficiency of slot nanojet impingement system. Impacts of pertinent parameters such as Reynolds number (Re between 250 and 1,000), strength of magnetic field (Ha between 0 and 30), permeability of the porous layer (Da between 0.001 and 0.1) on the cooling performance for flat and wavy surface configurations are explored.

Findings

It is observed that the average Nusselt number (Nu) rises by about 17% and 20.4% for flat and wavy configuration while temperature drop of 4 K is obtained when Re is increased to 1,000 from 250. By using magnetic field at the highest strength, the average Nu rises by about 29% and 7% for flat and wavy cases. Porous layer permeability is an effective way of controlling the cooling performance while up to 44.5% variations in the average Nu is obtained by varying its value. An optimization routine is used to achieve the highest cooling rate while the optimum parameter set is obtained as (Re, Ha, Da, γ, sx) = (1,000, 30, 0.07558, 86.28, 2.585) for flat surface and (Re, Ha, Da, γ, sx) = (1,000, 30, 0.07558, 71.85, 2.329) for wavy surface configurations.

Originality/value

In thermal systems, cooling system design is important for thermal management of various energy systems, including fuel cells, photovoltaic panels, electronic cooling and many others. Impinging jets are considered as effective way of cooling because of its ability to give higher local heat transfer coefficients. This paper offers novel control tools, such as magnetic field, installation of porous layer and hybrid nano-liquid utilization for control of cooling performance with multiple impinging jets.

Details

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

Keywords

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