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Article
Publication date: 30 December 2020

Amruta Joglekar-Athavale, Ganapati Shankarling, Satishchandra Dubey, Vinita Deshpande, Bikashkumar Jaiswal and Arun Nayak

The spectrally selective solar absorption paint is prepared from spinel-based mixed metal oxides with inorganic binder as a key component. Inorganic binder (furnace cement) is…

Abstract

Purpose

The spectrally selective solar absorption paint is prepared from spinel-based mixed metal oxides with inorganic binder as a key component. Inorganic binder (furnace cement) is blended with mixed metal oxide pigment during synthesis. High temperature stability upto 1,100ºC is achieved by the use of this modified coating system. The purpose of this paper is to work on solar selective coating synthesis, and application of a coating as a water-borne paint is the additive key feature that helps in reduction of solvent use.

Design/methodology/approach

The paint was formulated using water-based system, and the main component of colorant was made by mixed metal oxide–based spinel pigment and highly temperature stable inorganic binder.

Findings

The paint formed shows excellent absorptive power with low emittance even at high temperature. Optical and thermal properties were determined along with adhesion, abrasion and other properties. The solar absorptance for these samples were as = 0.93–0.95 with corresponding thermal emittance of eT = 0.096 (at room temperature) and 0.2–0.22 (at elevated temperature 100°C).

Originality/value

The paint formed shows excellent absorptive power with low emittance even at high temperature. The paint can be applied in solar absorptive tower system. The obtained results indicated excellent thermal stability of prepared paint coatings. As inorganic binder was used, the paint has reduction in solvent use, and being water as a base, it is environment friendly, easy to apply and durable at high temperatures, as the binder itself is stable up to 1,500ºC.

Details

Pigment & Resin Technology, vol. 50 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 13 January 2021

Amruta Joglekar-Athavale and Ganapti S. Shankarling

A mixed metal oxide-based spinel ceramic pigment has been successfully synthesized incorporating inorganic, high-temperature stable furnace cement as an inbuilt binder. Step by…

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Abstract

Purpose

A mixed metal oxide-based spinel ceramic pigment has been successfully synthesized incorporating inorganic, high-temperature stable furnace cement as an inbuilt binder. Step by step synthesis was done for the spinel and cement mix formulations.

Design/methodology/approach

The pigment mix was synthesized by a solid-solid method where the inorganic binder was incorporated in the mix. The results suggested that CoCuMn-based spinel ceramic pigment with cement mix could be obtained at an annealing temperature of 1,100ºC for 1 h and the size, morphology and crystallinity of spinel mix were greatly influenced by the calcination temperature.

Findings

The pigment mix synthesized was applied as a coating to different substrates such as aluminum, glass and Mild steel. The results revealed that spectral selectivity of TSSS paint coatings based on the CoMnCu spinel ceramic mix was much better than that of solvent-based coatings for high-temperature applications. The presence of cement as an inorganic binder makes the functioning and application of paint easy as it becomes that of a waterborne type.

Originality/value

Ease of application, stability at high temperatures, best absorptivity at the solar selective spectrum and excellent adhesion properties for the selected surface are the key features of the designed pigment system. The applied pigment mix was studied as a coating to get the results for solar selective system.

Details

Pigment & Resin Technology, vol. 50 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 28 June 2013

Fawzia Fahim Abdel‐Mohsen and Hassan Salah Aly Emira

This work aimed to prepare black transition metal oxide pigments to be used as solar absorbers in the solar selective and other industrial paints.

Abstract

Purpose

This work aimed to prepare black transition metal oxide pigments to be used as solar absorbers in the solar selective and other industrial paints.

Design/methodology/approach

Mixed metal oxide CoCuMnOx spinel pigments were synthesised via the sol‐gel route. These oxides, namely (I‐Co0.50Cu0.25Mn0.25)Ox, (II‐Co0.25Cu0.50Mn0.25)Ox and (III‐Co0.25Cu0.25Mn0.50)Ox, were prepared with different molar ratios and annealed at 600, 800 and 900°C, respectively. The prepared oxides were characterised by infrared spectrometer (IS), differential scanning calorimetry analysis (DSC), X‐ray diffraction (XRD) and transmission electron microscope (TEM).

Findings

The prepared pigments have a spinel structure with the composition CoCuMnOx. All synthesised pigments consisted of nano particles ranged from 10 to 80 nm. The optical properties showed high absorption and moderately low reflectance in the solar wavelength range.

Research limitations/implications

The prepared samples, used in the present work, were synthesized from cobalt sulphate, copper chloride and manganese chloride. The salts were dispersed in polyacrylamide as a precursor.

Practical implications

The prepared samples were thermally stable and had good optical properties. They could be used as absorber materials in the painting of solar collectors.

Originality/value

These thermally stable mixed metal oxides could be used in the painting of solar collectors. The three mixed metal oxides could be used as absorber materials for heating solar collectors due to their high absorption and moderately low reflectance in the solar wavelength range.

Details

Pigment & Resin Technology, vol. 42 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 2 November 2015

Fawzia Fahim Abdel-Mohsen and Hassan Salah Aly Emira

– The purpose of this study was to prepare colour pigments for use as spectrally selective coatings for solar absorbers.

Abstract

Purpose

The purpose of this study was to prepare colour pigments for use as spectrally selective coatings for solar absorbers.

Design/methodology/approach

Nano-particles cobalt and nickel oxides were prepared by sol–gel techniques. These oxides were prepared with its molar ratios and annealed at 200, 400, 600 and 800°C. The structure of the pigments was characterized by infrared spectrometer, differential scanning calorimetry analysis, X-ray diffraction, transmission electron microscope and scanning electron microscope.

Findings

Encapsulated cobalt and nickel oxides were completely formed at 800 and 600°C, and its colour was black and dark green, respectively. The results confirmed that black and green pigments combined selectivity with colour. Optical properties such as absorption and reflection were affected by the firing temperatures on cobalt and nickel oxides–gel polymers. All synthesized pigments consisted of nano-particles.

Research limitations/implications

The prepared samples used in the present work were synthesized from cobalt chloride and nickel acetate. The salts were dispersed in polyacrylamide as a precursor.

Practical implications

The prepared metal oxides had good solar properties.

Originality/value

Colour becomes more important for thermal solar collectors, and it has attracted interest. This might be related to a generally growing attention towards architectural integration of solar energy systems into building. Architects would prefer different colours besides black, even if lower efficiency would have to be accepted.

Article
Publication date: 23 March 2020

Majid Mazhar, Majid Abdouss, Farhad Zarifi and Mojdeh Zargaran

The purpose of this study is to investigate the performance of eight perylene diimide pigments as a hypothetical building facades using EnergyPlus.

Abstract

Purpose

The purpose of this study is to investigate the performance of eight perylene diimide pigments as a hypothetical building facades using EnergyPlus.

Design/methodology/approach

A hypothetical building located in Tehran is modeled using EnergyPlus, and the effectiveness of the pigments was examined. Furthermore, the performance of the pigments was compared with those of common commercial black (carbon black) and red (iron oxide) pigments.

Findings

The results show that the studied black pigments reduce the cooling energy demand up to 37 per cent in comparison with carbon black paint and the red ones, which reduce the value by as much as 32 per cent in comparison to iron oxide.

Originality/value

This study demonstrates that the application of cool paints rather than common paints will significantly reduce the cooling energy demand and subsequent costs.

Details

Pigment & Resin Technology, vol. 49 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 29 August 2018

Nwakaego Chikaodinaka Onyenokporo and Ekele Thompson Ochedi

The purpose of this paper is to develop a set of affordable retrofit packages that can be applied to existing residential buildings in hot-humid regions to improve occupants’…

Abstract

Purpose

The purpose of this paper is to develop a set of affordable retrofit packages that can be applied to existing residential buildings in hot-humid regions to improve occupants’ thermal comfort and reduce energy consumption.

Design/methodology/approach

A critical review of relevant literature to identify passive design strategies for improving thermal comfort and reducing energy consumption in hot-humid climates with focus on the building envelope was conducted in addition to a simulation study of an existing building typology in study area.

Findings

There is enormous potential to reduce energy costs and improve thermal comfort through building retrofit packages which is a recent concept in developing countries, such as Nigeria. Analysing the results of the retrofit interventions using building energy simulation helped in developing affordable retrofit packages which had optimum effect in improving indoor comfort temperature to the neutral temperature specified for hot humid Nigeria and further down to 3°C less than that of the reference building used. The use of passive design strategies to retrofit the building might help homeowners reduce their annual energy consumption by up to 46.3 per cent just by improving the indoor thermal comfort.

Originality/value

In addition to improving thermal comfort and reducing energy consumption, this research identified affordable retrofit packages and considered its cost implications especially to low-income earners who form a larger population of Lagos, Nigeria, as this was not considered by many previous researchers.

Details

International Journal of Building Pathology and Adaptation, vol. 37 no. 3
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 18 April 2008

This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting‐edge research and case studies.

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Abstract

Purpose

This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting‐edge research and case studies.

Design/methodology/approach

This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context.

Findings

The paper finds that increasing concerns about the effects of climate change have accelerated the search for less harmful energy sources. One of the outcomes has been renewed consideration of nuclear power as a serious alternative to fossil fuels. Shortage in the supplies of gas and oil has increased the appeal in some quarters. In every decade since the 1970s, nuclear energy has been the fastest growing major source of electricity. It produces 30 percent of the power used by the European Union (EU), with France taking over three‐fourths of its electricity supply from nuclear reactors. Nuclear also generates 20 percent of US energy, despite the country's recognized partiality to oil. Not surprisingly, however, this form of energy still struggles to gain universal approval and the mere mention of the “N” word still sends shivers down many spines.

Practical implications

The paper provides strategic insights and practical thinking that have influenced some of the world's leading organizations.

Originality/value

The briefing saves busy executives and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy‐to‐digest format.

Details

Strategic Direction, vol. 24 no. 6
Type: Research Article
ISSN: 0258-0543

Keywords

Article
Publication date: 1 March 1986

Walker Son and Packman

In accordance with instructions received through — we have carried out a detailed inspection of the subject property in order to advise you in connection with your proposed…

Abstract

In accordance with instructions received through — we have carried out a detailed inspection of the subject property in order to advise you in connection with your proposed purchase of a leasehold interest for an unexpired term of 12 years.

Details

Structural Survey, vol. 4 no. 3
Type: Research Article
ISSN: 0263-080X

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 Centre…

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

Article
Publication date: 23 December 2015

Sudhir Chitrapady Vishweshwara and Jalal Marhoon AL. Dhali

Sultanate of Oman witness a long summer with mostly clear blue skies and typically higher ambient temperatures as seen in other GCC countries. This type of environment warrants…

Abstract

Sultanate of Oman witness a long summer with mostly clear blue skies and typically higher ambient temperatures as seen in other GCC countries. This type of environment warrants the use of high capacity and reliable air conditioning systems, both at resident buildings and vehicles. During summer, cars parked directly under the sun, experience a very high temperature rise inside its cabin in the range of near to 50 °C. This high cabin air temperature often causes thermal discomfort to passengers entering the parked car and also has a serious impact on the cars air-conditioning systems, as it takes longer time to bring back the thermal comfort inside the cabin. The studies also revealed that the high cabin temperature often causes health hazards to occupants, especially to infants. Current research paper, reports an experimental study carried out on a parked car, with instrumentation to identify the various the temperature zones inside the car cabin. This experiential study is aimed to improve the thermal comfort inside the cabin through solar powered cabin air ventilator for effective management of cabin air temperature. The study was carried on a chosen vehicle parked at a set direction and location exposed to day long sunlight at Muscat for considerable period of time. Firstly, the study identified the various temperature zones inside the car cabin and ventilation driven with a 10 Wp solar panel was developed to accomplish the required air exchange inside the cabin, along with continues instantaneous heat rejection through steady air exchange between inside and outside environment. A simple ventilator was developed by means of two fans which drove out the hot trapped air and a secondary fan to cool down the temperature inside the car by providing fresh air for limited time. The experimental investigation showed that the vehicle cabin temperature was typically 10 °C lower when ventilator was turned on. On a typical day on month of May, the cabin air temperatures was approximately 21 °C higher than the ambient air temperature, while with the developed ventilator the difference between the cabin and outside air temperature was reduced by 50% approximately. With the ventilator in operation, it was observed that time taken to reduce the cabin air temperature through vehicle air conditioning system to a satisfactory level was much quicker; typically it took less than the half of the time compared to those values tested without ventilator. Thus indicating, the power saving potential of the developed system as the desired level of thermal comfort can be achieved within the shorter period of time. The reduction in time taken to cool down the cabin temperature to the acceptable limits has direct two fold effects; firstly, the fuel consumption for cooling purpose is reduced and secondly, increased thermal comfort level inside the cars cabin. However, the temperature drop pattern was not similar all around the cabin, due to the varied level of cabin sunlight exposure. Temperature drop at the front of the car was lower than in middle and rear of the car. From the study it can be concluded that, with solar powered ventilator, the temperature inside the car was nearly 10 °C lesser compared to cabin without ventilator and it also helps in to bring back the thermal comfort inside the cabin nearly within half time vis-à-vis cabin without ventilation.

Details

World Journal of Engineering, vol. 12 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

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