TY - JOUR
A1 - Jiang, Jin-Wu
A1 - Zhuang, Xiaoying
A1 - Rabczuk, Timon
T1 - Orientation dependent thermal conductance in single-layer MoS 2
JF - Scientific Reports
N2 - We investigate the thermal conductivity in the armchair and zigzag MoS2 nanoribbons, by combining the non-equilibrium Green's function approach and the first-principles method. A strong orientation dependence is observed in the thermal conductivity. Particularly, the thermal conductivity for the armchair MoS2 nanoribbon is about 673.6 Wm−1 K−1 in the armchair nanoribbon, and 841.1 Wm−1 K−1 in the zigzag nanoribbon at room temperature. By calculating the Caroli transmission, we disclose the underlying mechanism for this strong orientation dependence to be the fewer phonon transport channels in the armchair MoS2 nanoribbon in the frequency range of [150, 200] cm−1. Through the scaling of the phonon dispersion, we further illustrate that the thermal conductivity calculated for the MoS2 nanoribbon is esentially in consistent with the superior thermal conductivity found for graphene.
KW - Mechanische Eigenschaft
KW - Wärmeleitfähigkeit
KW - Nanoribbons, thermal conductivity
Y1 - 2013
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170418-31417
ER -
TY - JOUR
A1 - Vu-Bac, N.
A1 - Nguyen-Xuan, Hung
A1 - Chen, Lei
A1 - Lee, C.K.
A1 - Zi, Goangseup
A1 - Zhuang, Xiaoying
A1 - Liu, G.R.
A1 - Rabczuk, Timon
T1 - A phantom-node method with edge-based strain smoothing for linear elastic fracture mechanics
JF - Journal of Applied Mathematics
N2 - This paper presents a novel numerical procedure based on the combination of an edge-based smoothed finite element (ES-FEM) with a phantom-node method for 2D linear elastic fracture mechanics. In the standard phantom-node method, the cracks are formulated by adding phantom nodes, and the cracked element is replaced by two new superimposed elements. This approach is quite simple to implement into existing explicit finite element programs. The shape functions associated with discontinuous elements are similar to those of the standard finite elements, which leads to certain simplification with implementing in the existing codes. The phantom-node method allows modeling discontinuities at an arbitrary location in the mesh. The ES-FEM model owns a close-to-exact stiffness that is much softer than lower-order finite element methods (FEM). Taking advantage of both the ES-FEM and the phantom-node method, we introduce an edge-based strain smoothing technique for the phantom-node method. Numerical results show that the proposed method achieves high accuracy compared with the extended finite element method (XFEM) and other reference solutions.
KW - Finite-Elemente-Methode
KW - Steifigkeit
KW - Bruchmechanik
KW - Riss
Y1 - 2013
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170426-31676
ER -
TY - JOUR
A1 - Zhuang, Xiaoying
A1 - Huang, Runqiu
A1 - Liang, Chao
A1 - Rabczuk, Timon
T1 - A coupled thermo-hydro-mechanical model of jointed hard rock for compressed air energy storage
JF - Mathematical Problems in Engineering
N2 - Renewable energy resources such as wind and solar are intermittent, which causes instability when being connected to utility grid of electricity. Compressed air energy storage (CAES) provides an economic and technical viable solution to this problem by utilizing subsurface rock cavern to store the electricity generated by renewable energy in the form of compressed air. Though CAES has been used for over three decades, it is only restricted to salt rock or aquifers for air tightness reason. In this paper, the technical feasibility of utilizing hard rock for CAES is investigated by using a coupled thermo-hydro-mechanical (THM) modelling of nonisothermal gas flow. Governing equations are derived from the rules of energy balance, mass balance, and static equilibrium. Cyclic volumetric mass source and heat source models are applied to simulate the gas injection and production. Evaluation is carried out for intact rock and rock with discrete crack, respectively. In both cases, the heat and pressure losses using air mass control and supplementary air injection are compared.
KW - Energiespeicherung
KW - Druckluft
KW - Kaverne
KW - Modellierung
Y1 - 2014
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170428-31726
ER -