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Jan Stentoft, Ram Narasimhan and Thomas Poulsen
To support ongoing industry efforts to reduce the cost of energy (CoE) of offshore wind compared to other types of energy sources, researchers are applying scientific models and…
Abstract
Purpose
To support ongoing industry efforts to reduce the cost of energy (CoE) of offshore wind compared to other types of energy sources, researchers are applying scientific models and thought processes to identify potential areas of improvement and optimization. This paper aims to introduce a conceptual framework from a supply chain management (SCM) perspective, aimed at promoting the reduction of CoE in the offshore wind energy industry.
Design/methodology/approach
Using conceptual arguments from current academic literature in SCM, a comprehensive framework is presented that clarifies how SCM practices can be used by offshore wind energy industry to reduce CoE.
Findings
The offshore wind energy sector is a young industry that must reduce CoE to compete with other forms of energy. Applying a supply chain perspective in the offshore wind industry has hitherto been limited to the academic community. This paper offers a SCM framework that includes three interdependent aspects of reducing CoE – innovation, industrialization and supplier partnering – to guide the industry towards sources to reduce CoE.
Research limitations/implications
SCM is a broad research area; thus, the presented framework to reduce the CoE is open for further development.
Practical implications
The paper provides insights into how the CoE can be reduced through innovation, industrialization and partnering in the offshore wind energy supply chain.
Originality/value
The paper offers a seminal contribution by introducing a SCM framework to understand sources and approaches to reduce CoE in the offshore wind energy industry.
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Behnam Rajabzadeh, Mohammad Hojaji and Arash Karimipour
Porous medium has always been introduced as an environment for increasing heat transfer in cooling systems. However, increase in heat transfer and resolving pressure drop in the…
Abstract
Purpose
Porous medium has always been introduced as an environment for increasing heat transfer in cooling systems. However, increase in heat transfer and resolving pressure drop in the fluid flow have been focused on by researchers.The purpose of this paper is to study the effects of creating porous micro-channels inside porous macro-blocks to optimize system performance in channels.
Design/methodology/approach
To simulate flow field, a developed numerical code that solves Navier–Stokes equations by finite volume method and semi-implicit method for pressure linked equations (SIMPLE) algorithm will be used together with bi-disperse porous medium (BDPM) method. Working fluid is air with Pr = 0.7 in laminar state. Influence of permeability changes by creation of micro-channels containing porous medium in vertical, horizontal and cross-shape patterns will be investigated.
Findings
By creating porous micro-channels inside macro-blocks, not only does the heat transfer increase significantly but the pressure also drops remarkably. Increase in performance evaluation criteria (PEC) is more evident in lower Reynolds numbers that can increase the PEC to 75 per cent by creating cross-shape micro-channels. By changing the permeability of micro-channels, PEC will increase by reducing the pressure drop but it has minor changes in Nu.
Research limitations/implications
The current work is applicable to optimizing system performance by decreasing the pressure drop and increasing the heat transfer.
Practical implications
The developed patterns are useful in increasing the system performance including the increase in heat transfer and decrease in pressure drop in systems such as air coolers required in electrical circuits.
Originality/value
Development and optimization of system performance by new patterns using BDPM in comparison to the previous patterns.
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Keyur D. Vaghela, Bhavesh N. Chaudhary, Bhavbhuti Manojbhai Mehta, V.B. Darji and K.D. Aparnathi
There are various Kreis tests reported in the literature with wide variations in the procedure. The purpose of this paper is to select the most suitable and reliable method for…
Abstract
Purpose
There are various Kreis tests reported in the literature with wide variations in the procedure. The purpose of this paper is to select the most suitable and reliable method for the rancidity evaluation in ghee.
Design/methodology/approach
Ghee samples were prepared from butter by the direct cream method. They were assessed for early-stage oxidative deterioration by four Kreis tests in an accelerated storage trial at intervals of 48 h. The amount of ghee samples, amount of reagents (chloroform, 30 percent trichloroacetic acid, 1 percent phloroglucinol, and ethanol), incubation temperature and duration were different in the four tests. For each method, the ghee samples were also monitored for changes in flavor at intervals of 48 h by sensory evaluation. Relationships among the Kreis values determined by the four different Kreis tests and flavor scores were established using a correlation analysis.
Findings
The correlation coefficient of the Kreis values determined by different Kreis tests was in decreasing order of: Kreis test-2 (−0.904) > Kreis test-4 (−0.792) > Kreis test-3 (−0.648) > Kreis test-1 (−0.469). Thus, among the four different Kreis tests, Kreis Test-2 reported by Pool and Prater (1945) was found to be more sensitive and more consistent, and have the highest coefficient of correlation (−0.904) with flavor score of ghee during storage at 80±2°C.
Practical implications
The finding of this study will be useful for the selection of an appropriate and reliable Kreis test that can be used for detecting rancidity in ghee at an incipient stage. The development of rancidity in the ghee leads to formation of off-flavor and such an oxidized product is not accepted by the consumer; this leads to economic loss to the manufacturer. Detection of traces of rancidity at an early stage provides an opportunity for industry personnel to take suitable control measures and/or make decisions regarding utilization of the product.
Originality/value
The use of a reliable Kreis test that detects traces of rancidity in a ghee can be very useful for enabling suitable measures to be taken to prevent further oxidative deterioration or to dispose of the ghee as early as possible.
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