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According to ISO and ASTM specifications, nanoparticles are described as the particles with a size in the range of 1-100 µm with one or more dimensions, being the base of nanotechnology. In this study, a comprehensive review on the thermodynamic effects of nanoparticles on thermal origin is carried out. Firstly, the classification of nanoparticles, which includes organic, inorganic, and carbon-based nanoparticles are introduced. Then, various applications of nanoparticles in many fields including cosmetics, sunscreens, electronics, catalysis, mechanics, manufacturing, materials, environment, and energy harvesting are briefly highlighted. A comprehensive review on the recent research trends on the impacts of nanoparticles on thermal origin is collected and summarized. Afterwards, the physical, chemical, and thermal properties of nanoparticles are highlighted. In the end, a conclusion is withdrawn. [ABSTRACT FROM AUTHOR]

In this experimental study mainly focused the thermal property such as thermal resistance and heat transfer analysis for the air gap variations provided in between two glasses on window for the domestic purposes. Easily available surrounding air considered as the experimental mater because of its arrangements. Thermal resistance of inside, outside and glasses (both glasses have same thermal conductivity such as 0.78 W/mK) all are maintained as constant throughout the investigation. But only air gap distance increased from 2 mm to 14 mm with gradual increase focused. The thermal conductivity of air considered as 0.026 W/mK. Thermal resistance and heat transfer impact with respect to the air gap between glasses were identify with the help of graphical representations. [ABSTRACT FROM AUTHOR]

Adding solid particles of nanometer scale to fluids is one of the most important passive methods of enhancing heat transfer performance. However, this gives numerous chances to investigate new frontiers, but also raises remarkable difficulties. Nanofluids act as suspension that can be obtained by dispersing nanometer-sized nanoparticles (1-100nm) in host fluids with the aim of enhancing thermal properties. This paper is a review of recent studies on boiling heat transfer of nanofluids for pool and convective flow boiling of nanofluids. The research results, collected since 2012 to present of the recent survey are reviewed and briefly outlined. An emphasis is put on the enhancement and the deterioration of the boiling heat transfer coefficient and critical heat flux of pool and convective flow boiling of nanofluids. Other important parameters affecting the boiling of nanofluids are identified and discussed in this review. While preparing future studies is greatly encouraged in order make this phenomenon well understood. [ABSTRACT FROM AUTHOR]

Experiment and numerical analyses were conducted to study the thermal performance and circulation characteristic of the working fluid of a T-shaped vapor chamber special designed for the motorcycle LED light. The influences of heat loads and cooling magnitude were experimentally investigated. Results show that both the heat loads and cooling conditions have strong influences on the thermal performance of the vapor chamber, and the thermal resistance in the extended section occupies over 75.8% of the overall thermal resistance of the vapor chamber. Simulation results indicate that large pressure drop occurs along the extended section of the vapor chamber, and causes large temperature difference along the extended section. [ABSTRACT FROM AUTHOR]

This paper evaluates the behavior of cutting temperature under the influence of specific cutting parameters by applying both Factorial Design and the Surface Response Methodology. Cutting speed, the feed rate and type of material were selected as input parameters to perform this study. As type of material is a non quantitative factor, it is necessary to establish a particular index to define it. Although different properties were analyzed, the average stress between the yield and strength stresses was demonstrated as the most representative property to describe material. The experimental values of temperatures during the turning process were obtained with an infrared thermography camera and experiments were designed to run the statistical analysis with commercial software. Both the Factorial Design and Surface Response methodologies showed the influence that specific values of the input parameters had on cutting temperatures. Factorial Design allowed more accurate results, but more experiments had to be carried out, while the Surface Response Methodology provided suitable information with fewer tests. A comparison was made between the experimental and some analytical results, for example those obtained by Cook, and showed a good agreement. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of temperature dependence of radiative properties of a medium on radiation and natural convection interaction in a rectangular enclosure. The radiative transfer equation is solved using the discrete ordinates method, and the momentum, continuity, and energy equations are solved by the finite volume method. Effects of the conduction-to-radiation parameter, Rayleigh number, and optical thickness are discussed. Results show that temperature dependence of radiative properties affects the temperature gradient, and hence the energy transport even in relatively weak radiation condition. On the other hand, temperature dependence of radiative properties has relatively insignificant effects on convection characteristics, even though it does affect the way that energy transfers into the system. As conduction-to-radiation parameter is decreased or Rayleigh number is increased, the effects of temperature dependence of radiative properties become more significant. [ABSTRACT FROM AUTHOR]

The experimental research aims at the analysis of the thermal performance of a gas-liquid heat exchanger in a pilot plant. Results of the conducted experiment with a finned tubes thermosyphon heat exchanger using natural gas are presented. The installation was mounted at the exit of a flue gas from an existing steam generator "PK-4 " with total power of 2.88 MW in the boiler room of Vini, Sliven, Bulgaria. Different experiments were carried out at different loads of the steam generator in order to determine the efficiency of the heat exchanger. Based on these results the coefficient of heat transfer of flue gas to the finned tubes was determined, based on different modes of operation with crossed and straight pipe bundles. The effectiveness-number of transfer units method was used. [ABSTRACT FROM AUTHOR]

This work presents the development of an experimental set-up for measurements of thermal conductivity of solid materials, such as ceramics, polymers, rubbers, glasses, biological materials, etc. whose thermal conductivity lies in the approximate range between 0.1 and 2 W/mK. The set-up was designed on the principle of the single-sided guarded hot plate method. In order to find the optimal design for generation of traceable 1-D heat flux through an investigated 300 mm × 300 mm specimen, a numerical heat transfer finite element method analysis was performed. The principal components of the measuring apparatus, such as hot plate with thermopile, cold plate, and auxiliary hot plate, were constructed according to the obtained results of simulations. Software for the control of experiment and data acquisition was developed using the LabVIEW programming environment. [ABSTRACT FROM AUTHOR]

The paper deals with the modelling of heat conduction in periodically stratified composites with slant layering to boundaries. The relations of the homogenized model with microlocal parameters for the case of layering parallel to the boundary are transformed to conform to requirements of the composite geometry. The plane problem of periodically stratified half-space with slant layering heated by given boundary temperature is solved analytically. The obtained results are analysed and compared with the solutions for special cases: (1) homogenized half-space, (2) half-space with parallel layering to the boundary, and (3) half-space with vertical layering to the boundary. [ABSTRACT FROM AUTHOR]

This study presents a soft sensing model of coal quality for utility boilers. This model is based on the coal quality information obtained from exhaust gas. Themechanism modeling method combined with data driving theory is used in themodeling process. The procedure for solving the non-linear equations for coal quality applies the inner loop iteration of dry ash-free basis of S (Sdaf) and outside loop iteration of dry ash-free basis of N (Ndaf) within a limited range, and dry ash-free basis of C (Cdaf) is searched from the entire range during outside loopiteration. The upper and lower limits of Ndaf are defined according to the NOX content in the exhaust gas, thereby solving the iterative initial value selectionproblem. Finally, the effectiveness of the proposed method is verified via severalsimulations and comparisons, the results show that this method is credible andeffective and it can be used in power plant for control system optimization. [ABSTRACT FROM AUTHOR]