Search Results

1 - 10 of 376 items :

  • Thermal conductivity x
Clear All
Thermal Conductivity and Thermal Diffusivity of Biodiesel And Bioethanol Samples

References Assael, M. J. - Antoniadis , K. D. - Wu, J. 2008. New measurements of the thermal conductivity of PMMA, BK7, and Pyrex 7740 up to 450 K. In International Journal of Thermophysics, vol. 29, no. 4, pp. 1257-1266. Biodiesel. 2012. [online]. [Retrieved 2012-6-20]. Retrieved from: <http://www.habmigern2003.info/biogas/Biodiesel.html> Bioethanol , CTBE. 2012. [online]. [Retrieved 2012-6-23]. Retrieved from: <http://www.bioetanol.org.br/english/interna/ index.php?chave = bioethanol

Open access
Prediction Models for Thermal Conductivity of Cement-based Composites

REFERENCES 1. Baghban M H, Hovde P J, Jacobsen S: “Effect of internal hydrophobation, silica fume and w/c on water sorption of hardened cement pastes,” Proceedings , International Conference on Durability of Building Materials and Components (XII DBMC), Porto, Portugal, April 12-15, 2011, pp 1495-1502. 2. Justnes H, “Low water permeability through hydrophobicity,” Report , SINTEF Building and Infrastructure, Oslo, Norway, 2008. 3. Baghban M H, Hovde P J, Jacobsen S, “Analytical and experimental study on thermal conductivity of hardened cement

Open access
Using artificial neural network to predict dry density of soil from thermal conductivity

] Mitchell, J.K. (1991): Conduction phenomena: from theory to geotechnical practice. Geotechnique, 41(3), pp. 299-340. [7] Naidu, A.D., Singh, D.N. (2004): A generalized procedure for determining thermal resistivity of soils. International Journal of Thermal Sciences, 43, pp. 43-51. [8] Zhang, J.R., Liu, Z.Q. (2006): A study on the convective heat transfer coefficient of concrete in wind tunnel experiment. China Civil Engineering Journal, 39(9), pp. 39-42. [9] Tarnawski, V.R., Leong, W.H. (2000): Thermal conductivity of

Open access
An analysis of effective thermal conductivity of heterogeneous materials

References [1] Cengel, Y. A., (2003). Heat transfer: A practical approach. (2nd ed). New York, McGraw-Hill. [2] Ismail, M. I.; Ammar, A. S. A.; Elokeily, M. (1988). Heat Transfer through Textile Fabrics: Mathematical Model. Appl Math Model,12 (4), 434-440. 3] Bhattacharjee, D.; Kothari, V. K. (2009). Heat transfer through woven textiles. Int J Heat Mass Tran,52 (7–8), 2155-2160. [4] Ymashita Yoshihiro; Yamda Hiroakia; Hajimeb, M. (2008). Effective Thermal Conductivity of Plain Weave Fabric and its Composite Material Made from High

Open access
Efficiency of the Needle Probe Test for Evaluation of Thermal Conductivity of Composite Materials: Two-Scale Analysis

References [1] MOHSENIN N.N., Thermal properties of foods and agricultural materials, Gordon and Breach, New York, 1980. [2] CARSLAW H.S., JAEGER J.C., Conduction of heat in solids, Clarendon Press, Oxford, 1959. [3] RICHE F., SCHNEEBELI M., Microstructural change around a needle probe to measure thermal conductivity of snow, Journal of Glaciology, 2010, Vol. 56, No. 199. [4] FONTANA A.J., VERITH J., IKEDIALA J., REYES J., WACKER B., Thermal properties of selected foods using dual needle heat

Open access
An Analysis of Relations for Determining the Thermal Conductivity of Rigid Polymer Foams

References [1] Lykov A.V. (1971): Heat and Mass Exchange . – Moscow: Moscow Publishing House. [2] Collishaw P.G. and Evans J.R.G. (1994): An assessment of expressions for the apparent thermal conductivity of cellular materials. – Journal of Materials Science, vol.29, pp.486-498. [3] Gur′ev V.V., Žoludov V.S. and Petrov-Denisov V.G. (2003): Thermal Insulation in Industry. Theory and Calculations . – Moscow: Strojizdat. [4] Shi M., Li X. and Chen Y. (2006): Determination of effective thermal conductivity for polyurethane foam by use of

Open access
An Analysis of the Structure and Thermal Conductivity of Hollow Microsphere Filled Syntactic Foams

-resistant syntactic foams through binding hollow glass microspheres with phosphate adhesive. Materials Design, Vol. 95, 2016, pp. 32 - 38. [7] RYZHENKOV, A. - LOGINOVA, N. - BELYAEVA, E. - LAPIN, Y. - PRISCHEPOV, A.: Review of binding agents in syntactic foams for heat-insulating structures in power industry facilities. Modern Applied Science, Vol. 9, 2015, pp. 96 - 105. [8] GAO, J. - WANG, J. - XU, H. - WU, C.: Preparation and properties of hollow glass bead filled silicone rubber foams with low thermal conductivity. Materials Design, Vol. 46, 2013, pp. 491 - 496

Open access
Effective thermal conductivity of superfluid helium: laminar, turbulent and ballistic regimes

, Physical Review B , vol. 18, pp. 3112–3125, 1978. 6. D. S. Greywall, Thermal-conductivity measurements in liquid 4 He below 0.7k, Physical Review B , vol. 23, pp. 2152–2168, 1981. 7. H. J. Maris, Dissipative coefficients of superfluid helium, Physical Review A , vol. 7, pp. 2074–2081, 1973. 8. L. D. Landau, Theory of the superfluidity of helium II, Physical Review , vol. 60, no. 4, p. 356, 1941. 9. M. Sciacca, A. Sellitto, and D. Jou, Transition to ballistic regime for heat transport in helium II, Physics Letters A , vol. 378, pp. 2471

Open access
Network model for thermal conductivities of unidirectional fiber-reinforced composites

Abstract

An empirical network model has been developed to predict the in-plane thermal conductivities along arbitrary directions for unidirectional fiber-reinforced composites lamina. Measurements of thermal conductivities along different orientations were carried out. Good agreement was observed between values predicted by the network model and the experimental data; compared with the established analytical models, the newly proposed network model could give values with higher precision. Therefore, this network model is helpful to get a wider and more comprehensive understanding of heat transmission characteristics of fiber-reinforced composites and can be utilized as guidance to design and fabricate laminated composites with specific directional or specific locational thermal conductivities for structures that simultaneously perform mechanical and thermal functions, i.e. multifunctional structures (MFS).

Open access
Enhanced thermal conductivity of graphene nanoplatelets epoxy composites

Abstract

Efficient heat dissipation from modern electronic devices is a key issue for their proper performance. An important role in the assembly of electronic devices is played by polymers, due to their simple application and easiness of processing. The thermal conductivity of pure polymers is relatively low and addition of thermally conductive particles into polymer matrix is the method to enhance the overall thermal conductivity of the composite. The aim of the presented work is to examine a possibility of increasing the thermal conductivity of the filled epoxy resin systems, applicable for electrical insulation, by the use of composites filled with graphene nanoplatelets. It is remarkable that the addition of only 4 wt.% of graphene could lead to 132 % increase in thermal conductivity. In this study, several new aspects of graphene composites such as sedimentation effects or temperature dependence of thermal conductivity have been presented. The thermal conductivity results were also compared with the newest model. The obtained results show potential for application of the graphene nanocomposites for electrical insulation with enhanced thermal conductivity. This paper also presents and discusses the unique temperature dependencies of thermal conductivity in a wide temperature range, significant for full understanding thermal transport mechanisms.

Open access