Scattering kernels for the boundary conditions of the boltzmann equation on the moving boundary of two-phase systems

Meccanica ◽  
1978 ◽  
Vol 13 (3) ◽  
pp. 127-132 ◽  
Author(s):  
Nicola Bellomo ◽  
Roberto Monaco
Author(s):  
Zhaoli Guo ◽  
Baochang Shi ◽  
Chuguang Zheng

Spurious currents near an interface between different phases are a common undesirable feature of the lattice Boltzmann equation (LBE) method for two-phase systems. In this paper, we show that the spurious currents of a kinetic theory-based LBE have a significant dependence on the parity of the grid number of the underlying lattice, which can be attributed to the chequerboard effect. A technique that uses a Lax–Wendroff streaming is proposed to overcome this anomaly, and its performance is verified numerically.


2018 ◽  
Author(s):  
Chang-jiang Liu ◽  
Song Pang ◽  
Qiang Xu ◽  
Ling He ◽  
Shao-peng Yang ◽  
...  

2021 ◽  
Vol 0 (0) ◽  
pp. 0
Author(s):  
Corentin Le Bihan

<p style='text-indent:20px;'>In this paper we present a rigorous derivation of the Boltzmann equation in a compact domain with {isotropic} boundary conditions. We consider a system of <inline-formula><tex-math id="M1">\begin{document}$ N $\end{document}</tex-math></inline-formula> hard spheres of diameter <inline-formula><tex-math id="M2">\begin{document}$ \epsilon $\end{document}</tex-math></inline-formula> in a box <inline-formula><tex-math id="M3">\begin{document}$ \Lambda : = [0, 1]\times(\mathbb{R}/\mathbb{Z})^2 $\end{document}</tex-math></inline-formula>. When a particle meets the boundary of the domain, it is instantaneously reinjected into the box with a random direction, {but} conserving kinetic energy. We prove that the first marginal of the process converges in the scaling <inline-formula><tex-math id="M4">\begin{document}$ N\epsilon^2 = 1 $\end{document}</tex-math></inline-formula>, <inline-formula><tex-math id="M5">\begin{document}$ \epsilon\rightarrow 0 $\end{document}</tex-math></inline-formula> to the solution of the Boltzmann equation, with the same short time restriction of Lanford's classical theorem.</p>


2011 ◽  
Vol 90-93 ◽  
pp. 2528-2532
Author(s):  
Hong Wei Ma ◽  
Ji Wei Wang ◽  
Ji Xiang Xu

Based on fluid-solid two-phase coupling numerical model, this paper utilized velocity potential function theory to investigate the nonlinear interaction of water and free floating body. Meanwhile, multi-time step integral method and Overall numerical solution method, which are suitable for finite element dynamic analysis, and free surface boundary condition, not moving boundary conditions and the water-solid coupling boundary conditions are adopted to analyze the dynamic responses of water and free floating body with different dimensions. Numerical results show that the change of floating body sizes can obviously affect the dynamic characteristics of the fluid-solid coupling system, especially in the aspects of the stress responses of the floating body and the pressure responses of the water model.


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