Solar air heaters(SAHs)are widely used solar thermal systems with applications in diverse ***,its effectiveness is re-strained by low convective heat transfer(HT)coefficients at the absorber plate,leading to inefficie...
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Solar air heaters(SAHs)are widely used solar thermal systems with applications in diverse ***,its effectiveness is re-strained by low convective heat transfer(HT)coefficients at the absorber plate,leading to inefficient HT,and the elevated temperature of the absorber plate causes significant heat losses,reducing thermal *** study addresses these challenges by introducing ribs or roughness on the absorber plate creating turbulence in the airflow,resulting in significant *** research inves-tigates various rib configurations,the influence of rib parameters,performance methods,and arrangements to evaluate their HT and friction *** these rib configurations,a comparative analysis is done on various factors such as the Nusselt number ratio,thermal enhancement factor,friction factor ratio,and thermal efficiency to optimize distinct roughness parameters and rib ar-rangement *** study also provides valuable recommendations from existing literature,offering insights into the effective design,prospects,and implementation of SAH systems.
This study delves into the theoretical exploration of the effects of injector and orifice arrangement,spray angle,and orifice size on combustion and emission characteristics of horizontal opposed two-stroke *** employ...
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This study delves into the theoretical exploration of the effects of injector and orifice arrangement,spray angle,and orifice size on combustion and emission characteristics of horizontal opposed two-stroke *** employing numerical simulations,the research systematically investigates how variations in these parameters influence engine performance and *** findings underscore the significance of injector and orifice configuration in optimizing fuel spatial mixing and atomization,resulting in improved indicated thermal efficiency and indicated mean effective ***,it is noted that while emissions of HC,Soot,and CO can be maintained at low levels by injector and orifice configuration,NOxemissions tend to be relatively ***,the study highlights the impact of spray angle on combustion dynamics,where an optimum spray angle is identified for achieving peak thermal efficiency and effective pressure due to the improvement between spray distribution and ***,the study reveals the critical role of nozzle diameter in combustion and emissions control,with an optimal diameter leading to enhanced thermal efficiency and reduced emissions of Soot,HC,CO,and CO2 to some ***,these findings offer valuable insights into optimizing engine performance and emissions control strategies in horizontal opposed two-stroke engines,guiding future research and development efforts in the field.
This research examines a new approach to using medical waste as a raw material. There are two types of medical waste: hazardous and non-hazardous. More than 70% of medical waste is considered non-hazardous waste, obta...
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Ensuring high product quality is of paramount importance in pharmaceutical drug manufacturing,as it is subject to rigorous regulatory *** study presents a research focused on the development of an on-line detection me...
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Ensuring high product quality is of paramount importance in pharmaceutical drug manufacturing,as it is subject to rigorous regulatory *** study presents a research focused on the development of an on-line detection method and system for identifying surface defects in pharmaceutical products packaged in aluminum-plastic ***,the aluminum-plastic blister packages exhibit multi-scale features and inter-class *** address this,the deep semantic network with boundary refinement(DSN-BR)model is proposed,which leverages semantic segmentation domain knowledge,to accurately segment the defects in pixel ***,a specialized image acquisition module that minimizes the impact of ambient light is established,ensuring high-quality image ***,the image acquisition module,image detection module,and data management module are designed to construct a comprehensive online surface defect detection *** validate the effectiveness of our approach,we employ a real dataset for instance verification on the implemented *** experimental results substantiate the outstanding performance of the DSN-BR,achieving the mean intersection over union(MIoU)of 90.5%.Furthermore,the proposed system achieves an inference speed of up to 14.12 f/s,while attaining an F1-Score of 98.25%.These results demonstrate that the system meets the actual needs of the enterprise and provides theoretical and methodological support for intelligent inspection of product surface *** standardizing the control process of pharmaceutical manufacturing and improving the management capability of the manufacturing process,our approach holds significant market application prospects.
Thermal energy storage(TES) systems use solar energy despite its irregular availability and day-night temperature *** work reports the thermal characterizations of solar salt-based phase change composites in the prese...
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Thermal energy storage(TES) systems use solar energy despite its irregular availability and day-night temperature *** work reports the thermal characterizations of solar salt-based phase change composites in the presence of graphene nanoplatelets(GNP).Solar salt(60:40 of NaNO_(3):KNO_(3)) possessing phase transition temperature and melting enthalpy of 221.01℃ and 134.58 kJ/kg is proposed as a phase change material(PCM) for high-temperature solar-based energy storage *** conductivity must be improved to make them suitable for widespread applications and to close the gap between the system needs where they are *** is added at weight concentrations of 0.1%,0.3%,and 0.5% with solar salt using the ball milling method to boost its thermal *** studies indicated the formation of a uniform surface of GNP on solar *** spectrum peaks identified the physical interaction between salt and *** characterization of the composites,such as thermal conductivity,DSC and TGA was carried out for the samples earlier and later 300 thermal cycles.0.5% of GNP has improved the thermal conductivity of salt by 129.67% and after thermal cycling,the enhancement reduced to 125.21% indicating that thermal cycling has a minor impact on thermal *** change temperature decreased by around 2.32% in the presence of0.5% GNP and the latent heat reduced by 4.34% after thermal *** thermograms depicted the composites initiated the weight loss at around 550℃ after which it was *** thermal cycling,the weight loss initiated at ~40℃ lower compared to pure salt,which was found to be a minor *** characterization of solar salt and GNP-based solar salt composites revealed that the composites can be used for enhanced heat transfer in high-temperature solar-based heat transfer and energy storage applications.
Broad use of lightweight aluminium alloy parts in automobile manufacturing,aerospace,electronic communication,and rail transit is mainly formed through deep drawing *** drawing friction is a key boundary condition for...
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Broad use of lightweight aluminium alloy parts in automobile manufacturing,aerospace,electronic communication,and rail transit is mainly formed through deep drawing *** drawing friction is a key boundary condition for controlling the forming quality of aluminium alloy ***,due to the oxidation and adhesion tendency of aluminium alloys,the tribological situations of aluminium alloy deep drawing(AADD)system is more complicated than those of traditional deep drawing of steel ***,the study of AADD friction is essential for manufacturing high-performance aluminium alloy ***,aiming to provide a valuable reference for researchers in related fields,a comprehensive review of AADD friction is provided,including friction mechanism,influencing factors,friction measurement,friction model,friction simulation,and lubrication-free friction ***,a brief conclusion and several current challenges were discussed.
In this study,different conditions of sandblasting on dental implant fixtures were investigated to achieve the best sandblasting conditions.18 different sandblasting conditions(Using 152 implant fixture samples)were e...
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In this study,different conditions of sandblasting on dental implant fixtures were investigated to achieve the best sandblasting conditions.18 different sandblasting conditions(Using 152 implant fixture samples)were examined,including parameters such as particle size,particle blasting pressure,and particle blasting *** surface treatment of the samples was performed using the SLA+Anodizing *** testing was performed for each of the 18 different states,and the average surface roughness of each of these was compared with each ***,a bone layer was placed on the sample with the closest average surface roughness to the standard and the least amount of aluminum oxide on its surface among the 18 different states,to confirm the accuracy and quality of the desired surface roughness by examining the bone formation process and *** results showed that state No.4(sandblast particle size:75µm,spraying pressure of sandblast particles:4 bar,sandblast particle spraying angle:30 degrees),which was prepared using the SLA+Anodizing method and had a surface roughness of 1.989µm(The percentage of Al_(2)O_(3)on the surface=6%),had the best sandblasting conditions and showed 95%cell viability and accelerated the treatment and bone formation process for about a *** simulation results,using Abaqus software,indicated that the stress distribution on the surface of the implant fixture in contact with the bone surface has increased by approximately 4.3%for state *** will help prevent loosening of the dental implant fixture over time.
The instability of nanograined metals and the degradation of their mechanical properties primarily arise from pronounced grain boundary(GB)sliding and migration at extremely small grain sizes(GS).This study explores t...
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The instability of nanograined metals and the degradation of their mechanical properties primarily arise from pronounced grain boundary(GB)sliding and migration at extremely small grain sizes(GS).This study explores the incorporation of carbon nanotubes(CNTs)into nanocrystalline metals to enhance plastic flow stress by impeding metal *** results demonstrate that CNTs increase the critical stress of pure polycrystalline metals as GS *** relationship between plastic flow stress and GS in the composites is modeled using Hall-Petch and inverse Hall-Petch *** GS increases,the dominant plastic strengthening mechanism transitions from GB sliding hindrance via CNTs to a combined effect that mitigates GB sliding and intragranular stacking ***,the study evaluates how CNT length,wall number,and functionalization influence plastic ***,these findings provide a theoretical foundation for the design of mechanically stable nanocrystalline metal composites.
Thermocapillary migration in lubrication systems is a phenomenon in which the lubricant migrates via the interfacial tension difference caused by the nonuniform temperature generated by the wear behavior,which leads t...
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Thermocapillary migration in lubrication systems is a phenomenon in which the lubricant migrates via the interfacial tension difference caused by the nonuniform temperature generated by the wear behavior,which leads to lubricant starvation and results in severe *** paper proposes a novel method to eliminate the thermocapillary migration phenomenon,in which we successfully fabricate a surface that combines a shape gradient and wettability pattern on 316 L stainless steel,and the results prove that the prepared surface can not only effectively obstruct liquid paraffin droplet migration but also directionally transport liquid paraffin to the center of the wear track under the thermocapillary migration *** results of the wear tests further demonstrated that only the surface combination of a shape gradient and wettability pattern can achieve a decrease in the friction coefficient by means of external lubricant feeding in the state of lubricant starvation,which provides a strategy for improving and developing new types of lubrication enhancement for mitigating starvation lubrication.
With recent economic developments in India and a large thrust toward green technology and sustainability,tribology research has diversified from industrial maintenance and lubricant-centric tribology a few decades ago...
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With recent economic developments in India and a large thrust toward green technology and sustainability,tribology research has diversified from industrial maintenance and lubricant-centric tribology a few decades ago to new areas such as nanotribology,bio-tribology,smart coatings,wind turbine gears,and green *** this paper,a brief overview of the current research activities in tribological research in India is *** paper is divided into industrial and academic research,and their collaboration status is *** industry has continued to work on problems related to the maintenance of bearings,lubrication of machinery,mining equipment,etc.,but some new issues are presently being focused *** of these examples include problems related to wind turbine gears,hydrogen energy tribology,electric vehicle tribology,ship propellers,nuclear power plant tribology,bio-tribology,and so *** the academic environment,several new topics are being researched in different university/institute research ***-tribology and coatings have gained much momentum in academic research,but there is also a sufficient push towards new and environmentally friendly lubricant and grease additives for non-ferrous alloys,*** paper will also address some of the issues faced in industrial and academic tribological research arenas in India and how perhaps those issues could be addressed in the near future.
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