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Computational Heat Transfer
Published in Greg F. Naterer, Advanced Heat Transfer, 2018
This chapter described the most widely used methods of computational heat transfer, including the finite difference, finite element, and finite volume methods. In addition, further methods have been developed for specific physical processes or categories of problems. This last section will briefly highlight other methods based on the concepts of spectral elements, boundary elements, Monte Carlo methods, discrete ordinates, and high-resolution schemes.
Development of a thermal-hydraulic analysis code TAC-DS for spent fuel dry-storage system for high-temperature pebble bed reactor
Published in Journal of Nuclear Science and Technology, 2018
Bing Wang, Bin Wu, Rizwan uddin, Haijun Jia, Jinhua Wang
Uniformly volumetric heat load is assumed within each fuel domain according to the thermal power. A symmetry boundary is applied to the mid-plane of the simplified model. Air inlet and exit vents allow passive cooling by natural ventilation or active cooling by forced ventilation. High-resolution scheme is used in advection and turbulence discretization. k − ω SST turbulence model [25] is selected to model the turbulent effect. A turbulence intensity of 0.05 is specified at the inlet and outlet. In order to accurately model the flow and heat transfer behavior in the boundary layer, a fine grid with 10 inflation layers near the wall is employed. Thermal radiation between canister-barrel and barrel-concrete wall is modeled with discrete transfer model [25]. For natural ventilation condition, buoyancy model with a reference density of 1.13 kg/m3 (air density at ambient temperature of 312.55 K) is activated.
An Acoustic and Shock Wave Capturing Compact High-Order Gas-Kinetic Scheme with Spectral-Like Resolution
Published in International Journal of Computational Fluid Dynamics, 2020
Fengxiang Zhao, Xing Ji, Wei Shyy, Kun Xu
High-order and high-resolution schemes are needed in many applications related to the flows with small-scale structure and complex interaction, such as turbulence flow, shock and boundary layer interactions, and shock and vortex interactions. In the past decades, great effort has been paid on the development of high-order schemes for compressible Euler and Navier–Stokes equations with the co-existing smooth and discontinuous solutions (Harten, 1983; Harten et al., 1987; Shu and Osher, 1988; Liu, Osher, and Chan, 1994; Jiang and Shu, 1996). The reconstruction schemes of essentially non-oscillatory (ENO) (Harten et al., 1987; Shu and Osher, 1988) and weighted essentially non-oscillatory (WENO) (Liu, Osher, and Chan, 1994; Jiang and Shu, 1996) have received the most attention. ENO and WENO schemes can effectively distinguish the smooth and discontinuous shock in the reconstruction and maintain a uniformly high-order accuracy without obvious spurious oscillations in the unresolved region. The core of WENO scheme is to design smooth indicators and to obtain adaptive nonlinear convex combination of lower-order polynomials. WENO schemes can achieve very high-order accuracy in the smooth region and maintain essentially non-oscillatory property around discontinuities. In order to improve the accuracy and reduce the numerical dissipation of WENO schemes, the modified schemes, such as WENO-M and WENO-Z schemes (Henrick, Aslam, and Powers, 2005; Borges et al., 2008), have been developed. The hybrid schemes of combing high-order linear schemes and nonlinear WENO have been proposed as well (Ren, Liu, and Zhang, 2003; Hill and Pullin, 2004; Taylor, Wu, and Martín, 2007; Zhang et al., 2012). Most effort of these works is about the selection of optimal stencils and the design of weighting functions.