Begell House
International Journal for Multiscale Computational Engineering
International Journal for Multiscale Computational Engineering
1543-1649
15
3
2017
MOLECULAR DYNAMICS STUDY ON INTERFACIAL THERMAL RESISTANCE BETWEEN ORGANIC NANOPARTICLES AND ALKALI MOLTEN SALT MIXTURES
Interfacial thermal resistances between organic nanoparticles and liquid alkali molten salt mixtures were estimated using molecular dynamics simulations. In order to understand the interfacial thermal resistance behaviors as to different particles, three carbon particles−single-wall carbon nanotube (SWNT), fullerene (C60), and graphite sheets−were employed in this study. Transient heat transfer between a carbon particle and molecules of the molten salt mixtures were simulated on the basis of the lumped capacitance method. The effects of material properties, and particle shapes and sizes on the interfacial thermal resistance were investigated. Additionally, the characteristics of the molten salt mixture molecules in liquid phase were comprehended by plotting local density variations along the relative position from the particle: the existence of the compressed liquid layer was confirmed. Finally, the interfacial thermal resistance of functionalized SWNT using two functional groups (carboxylic and amine groups) was estimated and also the critical diameter of the nanoparticle which maximizes the thermal conductivity and the specific heat capacity of molten salt nanofluids was predicted.
Byeongnam
Jo
Department of Mechanical Engineering, Ajou University, Worldcup-ro 206, Yeongtong-gu, Suwon, 16499, Republic of Korea; Department of Mechanical Engineering, Texas A&M University, College Station, Texas 77843, USA
Debjyoti
Banerjee
Texas A&M University, Mechanical Engineering, MS 3123 TAMU, College Station, TX 77843-3123, USA
199-217
MODELING OF THIN COMPOSITE LAMINATES WITH GENERAL ANISOTROPY UNDER HARMONIC VIBRATIONS BY THE ASYMPTOTIC HOMOGENIZATION METHOD
A new approach to the asymptotic homogenization theory for thin composite laminates with general anisotropy of elastic modules under harmonic vibrations is suggested. The main purpose of the theory is to derive a closed explicit equation system for all six stress tensor components in composite laminates under vibrations, using 3D general equations for steady oscillations of elastic solids, by the asymptotic homogenization method. Unlike the classical homogenization analysis of 3D periodicity structures, our approach was applied to thin laminates with a constant thickness, but without any periodicity through the plate thickness. Recurrent chains of local vibration problems were deduced by the homogenization method, and closed-form solutions of these problems were found for thin laminates. This method allows us to compute all six stresses' distributions in a plate including normal through-thickness and shear interlayer stresses for the case of general anisotropy in elastic modules. Unlike the classical plate theories, for the case of general anisotropy in elastic modules, when there are 21 elastic constants, the displacements' distribution through a plate thickness is not linear. Longitudinal displacements proved to be linear functions of the coordinate along a plate thickness only for special anisotropy types−for monoclinic materials of plate layers, whose elastic modules' symmetry plane is parallel to a middle plane of the plate. Computations by the developed method and by a 3D-finite-element method solving the three-dimensional problem on free vibrations were compared, which showed a high accuracy of the developed method in calculation of natural frequencies and all six stresses in the plate.
Yu. I.
Dimitrienko
Computational Mathematics and Mathematical Physics Department, Bauman Moscow State Technical University, 2-nd Baumanskaya Str., 5, Moscow, 105005, Russia
I.D.
Dimitrienko
Computational Mathematics and Mathematical Physics Department, Bauman Moscow State Technical University, 2-nd Baumanskaya Str., 5, Moscow, 105005, Russia
219-237