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The shrinking size and increasing power consumption of electronic products also make their thermal management challenging. Poor thermal management results in increased temperature of the electronic component, ultimately leading to the failure of the element. Thermal management of electronic devices is assisted by-passive techniques such as heat sinks. Phase change material-filled heat sinks attract industries, as they are compact and do not require frequent maintenance. In this study, heat sinks with internal surface modifications, i.e., engraving and grit blasting, are developed. The heat sinks are provided with heat storage mediums like paraffin wax and nanoparticles to analyse their effect on thermal management. This study employed two different nanoparticles, i.e., silver titanium dioxide and graphene. A simple heat sink without surface modification and a heat storage medium was used as a reference. It was found that using graphene-mixed PCM in the smooth heat sink increased the charging time by about 8%. Adding graphene nanoparticles to the phase change material decreases the discharging time by about 29%. Grit-blasted heat sinks took the most time to discharge, followed by base-engraved heat sinks. This is because the internal surface roughened heat sinks stored more heat energy during the charging process. Adding graphene nanoparticles to the PCM increases the duty cycle by about 40%. When used with paraffin wax, base engraved heatsinks and grit-blasted heat sinks have increased the duty cycle by 11% and 36%, respectively. [ABSTRACT FROM AUTHOR]

The textile industry now produces thousands of tons of waste worldwide, and the total amount of discarded material waste increases yearly. Hygrothermal aging of cotton/E-glass (hybrid) fiber reinforced with various proportions of graphene oxide (0%, 1%, 3%, 5%, 7%, and 9%) was performed. Epoxy and vinyl ester (50:50) have been chosen because of the Interpenetrating Polymer Networks (IPNs) concept. Laminates were subjected to 50, 60, and 70°C temperatures for 180 days. Further, Tg and the degree of cross-linking have been determined by using differential scanning calorimetry (DSC). DSC analysis proves that a hot water bath enhances the cross-linking of the polymer. IPN laminates were also intermittently weighed for water uptake, and their consecutive mechanical properties like tensile, flexural, and impact strength were obtained. From this work, it was observed that the addition of 5 w.t% graphene oxide in cotton/E glass fiber vinyl ester/epoxy resin hybrid IPN composites showed a tensile strength of 375.61 MPa, flexural strength of 393.54 MPa, Interlaminar shear strength (ILSS) of 49 MPa and the impact strength of 22.54 MPa. Moreover, the lowest inclusion of particulate addition exhibits better mechanical properties than (up to 5% of GO) the highest particulate loading into the matrix. SEM study was conducted on the broken specimens to know the impact of diffusion characteristics on the physical properties of the IPN composites. Highlights • Natural and synthetic fibers are used as reinforcements. • Waste cotton/E glass fiber vinyl epoxy composites are fabricated. • Laminates were subjected to diverse temperatures for 180 days. • The moisture diffusion coefficient is proportional to water temperature. • Bathtub temperature affects the tensile strength of the laminate. [ABSTRACT FROM AUTHOR]

The increased durability and performance features of polymer concrete panels have led to their widespread application in construction. The manufacturing of precise and effective techniques for identifying forms and flaws is vital to guarantee the high quality of these panels. To increase the accuracy of structure and defect-recognition in polymer concrete panels, this study presents a new Stochastic raven roosting optimization enhanced artificial neural network (SRRO-EANN) forecasting technique. The data sample used to assess the completed model fits the training dataset is referred to the test dataset. The Gaussian filter (GF) is a tool used in the pre-processing and Principal Component Analysis (PCA) feature extraction, leading to more effective utilization and understanding the defect capturing. The findings of the research indicate the effectiveness for the future development of forecasting technologies in the realm of quality control and building material inspection. [ABSTRACT FROM AUTHOR]

This study is aimed at reducing NOx, Smoke, HC, CO emissions from single-cylinder, four-stroke, and water cooled diesel engine. The research engine is fueled with diesel and two blends of butanol and diesel at atmospheric conditions. Neat diesel is termed as D100, 10%, and 20% Volume of butanol dispersed in D100 is termed as D90B10 and D80B20 respectively. The chemical and physical properties of D100, D90B10 and D80B20 fall within the limits of ASTM standards. Results revealed that enhanced chemical properties and higher latent heat of vaporization of butanol lowered the CO, HC, smoke, and NOX emissions of diesel fueled research diesel engine. [ABSTRACT FROM AUTHOR]

This study examines the effect of concentration and flow-rate of CeO2 nano-fluid to reduce smoke emissions from a diesel engine. Taguchi-Grey relational-based multi-response optimization method was employed for test-plan. Results revealed that nano-fluid flow-rate and its concentration have a positive impact on smoke emissions reduction in a diesel engine. It is confirmed that the results obtained in the experimentations are in line with the calculated values obtained Taguchi technique. The usage of nano-fluid in the tailpipe is an effective way of reducing Smoke emissions from a diesel engine. [ABSTRACT FROM AUTHOR]

Ever increasing energy demand ever encourage for new energy production and conservation. In the present work, the cascaded latent heat solar thermal energy storage system has been developed to deliver the heat at different temperature limits and its performance on the improvement of heat transfer characteristics are studied with the use of multiple phase change material (PCM) with various encapsulation arrangements. The storage system consists of three different PCM which have different melting temperatures such as D-mannitol, D-sorbitol, and paraffin wax. Each PCM is encapsulated in different materials of spherical balls like copper, aluminum, and brass. Permanent welding of fins, inside the encapsulated balls of type rectangular, annular and pin is done for enhanced heat transfer. This work investigates for the best combination of fins which may allow the highest heat transfer rate for the least cost. It has been concluded that the transfer of energy is the highest in the use of copper balls for encapsulation of PCM with the attachment of annular fin inside the balls. With respect to energy cost per kJ of heat transfer, the PCM encapsulated in aluminum balls with annular fins may be preferred. However, in all the combinations, to gain higher efficiency of the system proper arrangements of all system components very close to each other is essential to the provision of perfect insulated storage tanks and the components of the piping circuit. [ABSTRACT FROM AUTHOR]

Alcohol will be an exceptional alternative fuel for existing diesel engines because of its built-in fuel-improving properties (high cetane number and high energy content). Biosynthesis of N-heptanol by means of engineered microbes, such as the Clostridium species and Escherichia coli, is an active area of research. Hence, extensive investigation on the compatibility of N-heptanol in existing diesel engines is necessary. This study examined the effect of heptanol mustard oil biodiesel blends of varying proportions on the emission and performance patterns in a 1,800 r/min constant-speed immobile diesel engine. The main objective of this investigation was to investigate the reduction in all the emissions and increase the performance characteristics associated with neat mustard oil biodiesel when deploying three different fuels. Base catalyzed transesterification process was employed to convert the mustard oil into mustard oil biodiesel. Heptanol with 98.4 % purity was used as an oxygenated additive. The experimental results revealed that converting heptanol to mustard oil biodiesel caused a significant reduction in hydrocarbons, carbon monoxide, nitrogen oxides, and smoke emissions when compared to mustard oil biodiesel in naturally aspirated conditions. [ABSTRACT FROM AUTHOR]

This study represents the exergy analysis of the evacuated tube parabolic trough collector and the cascaded latent heat storage system using multi-temperature phase change material (PCMs) during the charging process. The objective of the work is to control the losses and increase the efficiency of the system. The exergy analysis has been conducted on the basis of the first and second laws of thermodynamics in a parabolic trough collector with various mass flow rates of the heat transfer fluid (HTF). The overall variation of exergy efficiency of the collector with varying mass flow rate of the HTF is 5.9 %. The thermodynamic analysis of the cascaded latent heat storage system has been done during the charging process in which the PCM absorbs energy from the HTF and undergoes a phase transformation from the solid to the liquid state. The exergy analysis is conducted by varying the mass flow rate of the HTF in the storage system for both insulated and non-insulated systems. It is noticed that the variation of exergy stored for 5 and 10 liters per minute is 24.609 kW and 40.48 kW, respectively. It is concluded that the high range of energy and exergy stored in the system is achieved by the high flow rate of the HTF. [ABSTRACT FROM AUTHOR]

The present experimental work investigates the use of ethyne gas in biodiesel-fueled diesel engine at different flow rate of 1, 2, and 3 L/min and is compared with diesel operation. This work is aimed to examine the outcome of ethyne gas by dual-fuel operation on emission characteristics of neat biodiesel-fueled stationary diesel engine. The oil derived from mustard seeds are employed as a source for biodiesel. The work was carried out at 2100 rpm (speed) and at an optimal compression ratio of 17. Based on the outcome of this investigation, the maximum reduction in hydrocarbon (25.1%), carbon monoxide (17.24%), and smoke emission (24.8%) was observed for biodiesel-ethyne at 3 L/min than the neat biodiesel. However, NOx emissions were found to be 15.8% higher for ethyne-biodiesel fueling at 3 L/min owing to increase in combustion gas temperature than neat biodiesel. [ABSTRACT FROM AUTHOR]

This work investigates the effect of urea injection parameters on the reduction of NOxemissions from a 4-stroke twin-cylinder diesel engine fueled with neat biodiesel. The test plan was designed by employing L9(34) Taguchi orthogonal array. It has been experimentally found that the concentration of urea, the flow rate of urea and increase in spray angle has a significant effect on reducing in NOxemissions of the diesel engine when fuelled with neat biodiesel. Further, ANOVA results reveal that the concentration and flow rate of urea are the major parameters in reducing NOxemissions whereas, mixing length and spray angle have minimal effect on reduction in NOxemissions. Since the predicted value derived from Taguchi technique is in accordance with the test results from the confirmation test, the predictive capability of this technique in the study shall be inferred. [ABSTRACT FROM PUBLISHER]

In this study, neat biodiesel with octanol additive was employed in a diesel engine and its effects on engine emission were studied. The five fuels evaluated were neat palm kernal oil biodiesel, octanol blended with biodiesel by 10%, 20%, and 30% volume, and diesel. All the emissions are reduced by the addition of octanol in biodiesel in all loads owing to the higher oxygen concentration of air/fuel mixtures and improved atomization. Hence, it is concluded that the neat biodiesel and octanol blends can be employed as an alternative fuel for existing unmodified diesel engines owing to its lesser emission characteristics. [ABSTRACT FROM PUBLISHER]

The present work is intended to investigate the emission characteristics of neat cashew nut shell methyl ester (CNSME100) by adding pentanol at two different proportions and compared with the baseline diesel. CNSME100 is prepared by the conventional transesterification process. CNSME100 is chosen due to its non-edible nature. Pentanol is chosen as an additive because of its higher inbuilt oxygen content and surface to volume ratio which reduces the drawbacks of neat CNSME100. Emission characteristics were carried out in single cylinder naturally aspirated CI engine fuelled with neat cashew nut shell methyl ester (CNSME), cashew nut shell methyl ester and pentanol by 10% volume (CNSME90P10), cashew nut shell methyl ester and pentanol by 20% volume (CNSME80P20), and diesel. This work also aims to investigate the feasibility of operating an engine fuelled with neat methyl ester and alcohol blends. Experimental results showed that by blending higher alcohol to neat cashew nut shell methyl ester reduces the emissions significantly. It is also found that the emission from neat methyl ester and pentanol blends is lesser than diesel at all loads. [ABSTRACT FROM AUTHOR]