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Article
Publication date: 15 October 2020

Bishwajeet Pandey, Geetam Singh Tomar, Robin Singh Bhadoria, Dil Muhammad Akbar Hussain and Ciro Rodriguez Rodriguez

The Purpose of this research is to make an energy efficient finite state machine (FSM) in order to achieve the core objective of green computing because FSM is an…

Abstract

Purpose

The Purpose of this research is to make an energy efficient finite state machine (FSM) in order to achieve the core objective of green computing because FSM is an indispensable part of multiple computer hardware.

Design/methodology/approach

This study uses ultra-scale plus FPGA architecture in place of seven-series field-programmable gate array (FPGA) for the implementation of the FSM design and also uses output load scaling for the design of environment-friendly FSM. This design study is done using Verilog Hardware description language and Vivado integrated system environment design tools and implemented on 16 nm ultra-scale FPGA architecture.

Findings

There is up to 98.57% reduction in dynamic power when operating frequency is managed as per smart job scheduling. There is up to a 21.97% reduction in static power with proper management of output load capacitance. There is up to 98.43% saving in dynamic power with the proposed management of output load capacitance.

Originality/value

The proposed design will be environment friendly that eventually leads to the green earth. This is the main motive of the research area i.e. green computing.

Details

World Journal of Engineering, vol. 18 no. 4
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 4 September 2018

Evangelos Bellos, Ilias Daniil and Christos Tzivanidis

The purpose of this paper is to investigate a cylindrical flow insert for a parabolic trough solar collector. Centrally placed and eccentric placed inserts are…

Abstract

Purpose

The purpose of this paper is to investigate a cylindrical flow insert for a parabolic trough solar collector. Centrally placed and eccentric placed inserts are investigated in a systematic way to determine which configuration leads to the maximum thermal enhancement.

Design/methodology/approach

The analysis is performed in SolidWorks Flow Simulation with a validated computational fluid dynamics model. Moreover, the useful heat production and the pumping work demand increase are evaluated using the exergy and the overall efficiency criteria. The different scenarios are compared for inlet temperature of 600 K, flow rate of 100 L/min and Syltherm 800 as the working fluid. Moreover, the inlet temperature is examined from 450 to 650 K, and the diameter of the insert is investigated up to 50 mm.

Findings

According to the final results, the use of a cylindrical insert of 30 mm diameter is the most sustainable choice which leads to 0.56 per cent thermal efficiency enhancement. This insert was examined in various eccentric positions, and it is found that the optimum location is 10 mm over the initial position in the vertical direction. The thermal enhancement, in this case, is about 0.69 per cent. The pumping work demand was increased about three times with the insert of 30 mm, but the absolute values of this parameter are too low compared to the useful heat production. So, it is proved that the increase in the pumping work is not able to eliminate the useful heat production increase. Moreover, the thermal enhancement is found to be greater at higher temperature levels and can reach up to 1 per cent for an inlet temperature of r650 K.

Originality/value

The present work is a systematic investigation of the cylindrical flow insert in a parabolic trough collector. Different diameters of this insert, as well as different positions in two dimensions, are examined using a parametrization of angle-radius. To the authors’ knowledge, there is no other study in the literature that investigates the presented many cases systematically with the followed methodology on parabolic trough collectors. Moreover, the results of this work are evaluated with various criteria (thermal, exergy and overall efficiency), something which is not found in the literature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 18 March 2020

Muhammad Sohail and Rabeeah Raza

The current determination is committed to characterize the boundary layer flow of Williamson nanofluid prompted by nonlinear strained superficial under heat and mass…

Abstract

Purpose

The current determination is committed to characterize the boundary layer flow of Williamson nanofluid prompted by nonlinear strained superficial under heat and mass transport mechanisms. Buongiorno model is presented to view the influence of nanoparticles in fluid flow. Scrutiny has been conceded under the action of the transversely smeared magnetic field. Heat and mass relocation exploration are conducted in the companionship of radiation effects and actinic compensation.

Design/methodology/approach

Similarity variable is designated to transmute nonlinear partial differential equations of conservation laws of mass, momentum, energy and species into ordinary dimensional expressions. These constitutive and complicated ordinary differential expressions assessing the flow situation are handled efficaciously by manipulating Runge–Kutta–Fehlberg procedure (RK-5) with shooting routine.

Findings

The graphical demonstration is deliberated to scrutinize the variation in velocity, temperature and concentration profiles with respect to flow regulating parameters. Numerical data are displayed through tables in order to surmise variation in skin friction coefficient and Nusselt number. The augmenting values of fluid parameter and magnetic parameter reduces the horizontal fluid velocity, whereas normal velocity upsurges for mounting values of stretching ratio parameter. Moreover, mounting values of radiation parameter and thermophoresis parameter upsurges the temperature profile, whereas, growing values of Prandtl number lessen the temperature field.

Practical implications

The current exploration is used in many industrial and engineering applications in order to discuss the transport phenomenon.

Originality/value

Flow over a nonlinear stretched surface has numerous applications in the industry. The present attempt examines the combined influence of various physical characteristics for the flow of Williamson fluid and no such attempt exist in the available literature.

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 5
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 8 May 2018

Hugo Rodriguez-Ignacio, Xose M. Lopez-Fernandez and Casimiro Álvarez-Mariño

The purpose of this paper is to present a methodology based on an optimizer linked with electric finite element method (FEM) for automating the optimized design of power…

Abstract

Purpose

The purpose of this paper is to present a methodology based on an optimizer linked with electric finite element method (FEM) for automating the optimized design of power transformer insulation system structures.

Design/methodology/approach

The proposed methodology combines two stages to obtain the optimized design of transformer insulation system structures. First, an analytical calculation is carried out with the optimizer to search a candidate solution. Then, the candidate solution is numerically checked in detail to validate its consistency. Otherwise, these two steps are iteratively repeated until the optimizer finds a candidate solution according to the objective function.

Findings

The solutions found applying the proposed methodology reduce the inter-electrode distances compared to those insulation designs referenced in the literature for the same value of safety margin.

Originality/value

The proposed methodology explores a wide range of insulation system structures in an automated way which is not possible to do with the classical trial-and-error approach based on personal expertise.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 37 no. 3
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 February 1983

D. Boswell

This paper reviews the need for a more realistic and professional approach by UK OEM circuit designers and hybrid engineers to the philosophy and practice of long…

Abstract

This paper reviews the need for a more realistic and professional approach by UK OEM circuit designers and hybrid engineers to the philosophy and practice of long life—‘total excursion’—tolerancing. It offers simple methods, including offset calculations, for both thick film resistors and multilayer ceramic chip capacitors (X7R), e.g., in B/T Class 1 and Class 2 applications. Acceptance of these principles enables improved product life for the same initial setting (selection) tolerance and width.

Details

Microelectronics International, vol. 1 no. 2
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 3 May 2016

Amos Madhlopa

The purpose of this paper is to investigate a wall-integrated solar chimney for passive ventilation of a building cavity. Ventilation is required to improve the…

Abstract

Purpose

The purpose of this paper is to investigate a wall-integrated solar chimney for passive ventilation of a building cavity. Ventilation is required to improve the circulation of air in the built environment. This can be achieved through natural or forced convection. Natural circulation can be driven by renewable energy, and so it promotes sustainable exploitation of energy resources. Solar energy is one of the promising renewable energy resources.

Design/methodology/approach

The chimney was designed to face the Equator on the wall of a room which required ventilation. Mean monthly daily heating and cooling loads of the room were computed with and without a solar chimney by using hourly meteorological data from nine different weather sites at low, medium and high latitudes. The chimney was implemented with and without airflow control, and simulated by using the ESP-r software.

Findings

Results show that the solar chimney with airflow control marginally reduced the heating load in the building envelope, with a similar effect being exhibited by the chimney with uncontrolled airflow. The cooling load was reduced by the controlled airflow at all the nine sites. In contrast, the uncontrolled airflow increased the cooling load at some sites. In addition, the chimney with airflow control reduced the annual total thermal load at all the sites, while the chimney with uncontrolled airflow raised the total thermal load at some locations.

Originality/value

The performance of solar chimneys designed with and without airflow control systems has been investigated under the same prevailing meteorological conditions at a given site. Findings show that controlling airflow in a solar chimney reduces the total thermal load in the built environment. This information can be applied in different parts of the world.

Details

Journal of Engineering, Design and Technology, vol. 14 no. 2
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 26 February 2021

Subhasree Dutta, Somnath Bhattacharyya and Ioan Pop

The purpose of this study is to analyze the heat transfer and flow enhancement of an Al2O3-water nanofluid filling an inclined channel whose lower wall is embedded with…

Abstract

Purpose

The purpose of this study is to analyze the heat transfer and flow enhancement of an Al2O3-water nanofluid filling an inclined channel whose lower wall is embedded with periodically placed discrete hydrophobic heat sources. Formation of a thin depletion layer of low viscosity over each hydrophobic heated patch leads to the velocity slip and temperature jump condition at the interface of the hydrophobic patch.

Design/methodology/approach

The mixed convection of the nanofluid is analysed based on the two-phase non-homogeneous model. The governing equations are solved numerically through a control volume approach. A periodic boundary condition is adopted along the longitudinal direction of the modulated channel. A velocity slip and temperature jump condition are imposed along with the hydrophobic heated stripes. The paper has validated the present non-homogeneous model with existing experimental and numerical results for particular cases. The impact of temperature jump condition and slip velocity on the flow and thermal field of the nanofluid in mixed convection is analysed for a wide range of governing parameters, namely, Reynolds number (50 ≤ Re ≤ 150), Grashof number ( 103Gr5×104), nanoparticle bulk volume fraction ( 0.01φb0.05), nanoparticle diameter ( 30dp60) and the angle of inclination ( 60°σ60°).

Findings

The presence of the thin depletion layer above the heated stripes reduces the heat transfer and augments the volume flow rate. Consideration of the nanofluid as a coolant enhances the rate of heat transfer, as well as the entropy generation and friction factor compared to the clear fluid. However, the rate of increment in heat transfer suppresses by a significant margin of the loss due to enhanced entropy generation and friction factor. Heat transfer performance of the channel diminishes as the channel inclination angle with the horizontal is increased. The paper has also compared the non-homogeneous model with the corresponding homogeneous model. In the non-homogeneous formulation, the nanoparticle distribution is directly affected by the slip conditions by virtue of the no-normal flux of nanoparticles on the slip planes. For this, the slip stripes augment the impact of nanoparticle volume fraction compared to the no-slip case.

Originality/value

This paper finds that the periodically arranged hydrophobic heat sources on the lower wall of the channel create a significant augmentation in the volume flow rate, which may be crucial to augment the transport process in mini- or micro-channels. This type of configuration has not been addressed in the existing literature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 9
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 2 February 2015

Shuo Xiao , Yang Zhao , Yuan Cao, Haifeng Jiang and Wenliang Zhu

– This paper aims to deduce a set of theory computational formula, and optimize and improve the heat conductivity of vias in printed circuit boards of electrical power apparatus.

Abstract

Purpose

This paper aims to deduce a set of theory computational formula, and optimize and improve the heat conductivity of vias in printed circuit boards of electrical power apparatus.

Design/methodology/approach

The authors adopted numerical simulation and experimental measurement to verify the reliability of this formula.

Findings

Research result showed that 0.45 mm was the optimal bore diameter of vias; the conductivity had no obvious improvement when filling material was FR4 or Rogers, but if it was filled with texture of high thermal conductivity like soldering tine, the conductivity would improve a lot; the plating thickness of vias had a greater influence on thermal conductivity.

Originality/value

Through the theory computational formula, this paper studied the influence of aperture of vias, filled materials and thickness of copper plated on vias on thermal conductivity.

Details

Circuit World, vol. 41 no. 1
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 25 January 2008

Gilbert Justin Jose Nesamani, Sunil Chandrakant Joshi, Zhanli Jin, Poh Keong Chan and Soon Cheng Lee

This paper seeks to provide an insight into the design and development of the thermal test model (TTM) of X‐Sat, a 120 kg class micro‐satellite, being developed at the…

Abstract

Purpose

This paper seeks to provide an insight into the design and development of the thermal test model (TTM) of X‐Sat, a 120 kg class micro‐satellite, being developed at the Centre. This model was specifically constructed for carrying out a thermal balance test (TBT) in a 4 m diameter vertical thermal vacuum chamber.

Design/methodology/approach

The construction of the thermal model followed a structural mock‐up model which was modified thermally to suit the purpose. Specific and careful consideration was given to the geometry and, more importantly, thermal characteristics such as thermal mass, surface properties, etc. to mimic the actual satellite configuration as closely as possible. Test plans were devised to qualify the fabricated components to meet the out‐gassing and other thermal requirements for the model. Design and qualification of supporting frame and linkages for TBT are also covered.

Findings

It is possible to simulate the thermal characteristics of a micro‐satellite in orbit under a different mission scenario through proper scaling and using alternative material options while developing TTM.

Originality/value

The paper discusses in detail the simplified cost‐effective approach of constructing TTM and also outlines the various issues to be considered for a TBT. It provides valuable information needed for micro‐satellite designers.

Details

Aircraft Engineering and Aerospace Technology, vol. 80 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

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Article
Publication date: 5 September 2016

Åsa Grytli Tveten, Jon Gustav Kirkerud and Torjus Folsland Bolkesjø

This study aims to investigate the effects of thermal–hydro interconnection on the revenues, market value and curtailment of variable renewable energy (VRE). The…

Abstract

Purpose

This study aims to investigate the effects of thermal–hydro interconnection on the revenues, market value and curtailment of variable renewable energy (VRE). The increasing market shares of VRE sources in the Northern European power system cause declining revenues for VRE producers, because of the merit-order effect. A sparsely studied flexibility measure for mitigating the drop in the VRE market value is increased interconnection between thermal- and hydropower-dominated regions.

Design/methodology/approach

A comprehensive partial equilibrium model with a high spatial and temporal resolution is applied for the analysis.

Findings

Model simulation results for 2030 show that thermal–hydro interconnection will cause exchange patterns that to a larger extent follow VRE production patterns, causing significantly reduced VRE curtailment. Wind value factors are found to decrease in the hydropower-dominated regions and increase in thermal power-dominated regions. Because of increased average electricity prices in most regions, the revenues are, however, found to increase for all VRE technologies. By only assuming the planned increases in transmission capacity, total VRE revenues are found to increase by 3.3 per cent and VRE electricity generation increases by 3.7 TWh.

Originality/value

The current study is, to the authors' knowledge, the first to analyze the effect of interconnection between thermal- and hydropower-dominated regions on the VRE market value, and the authors conclude that this is a promising flexibility measure for mitigating the value-drop of VRE caused by the merit-order effect. The study results demonstrate the importance of taking the whole power system into consideration when planning future transmission capacity expansions.

Details

International Journal of Energy Sector Management, vol. 10 no. 3
Type: Research Article
ISSN: 1750-6220

Keywords

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