Time‐dependent rototranslational diffusion equation with multiple mixed boundary conditions: A formally exact analytical solution

1992 ◽  
Vol 33 (6) ◽  
pp. 2329-2335 ◽  
Author(s):  
M. Baldo ◽  
A. Grassi ◽  
A. Raudino
Keyword(s):  
Analytical Solution ◽  
Diffusion Equation ◽  
Boundary Conditions ◽  
Mixed Boundary ◽  
Exact Analytical Solution ◽  
Mixed Boundary Conditions ◽  
Time Dependent

scholarly journals Lattice-Boltzmann Simulations of the Convection-Diffusion Equation with Different Reactive Boundary Conditions

Mathematics ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 13
Author(s):  
Rui Du ◽  
Jincheng Wang ◽  
Dongke Sun
Keyword(s):  
Diffusion Equation ◽  
Boundary Conditions ◽  
Lattice Boltzmann ◽  
Mixed Boundary ◽  
Interpolation Method ◽  
Mixed Boundary Conditions ◽  
Convection Diffusion ◽  
Convection Diffusion Equation ◽  
Lattice Boltzmann Simulations ◽  
Accuracy And Stability

We have tested the accuracy and stability of lattice-Boltzmann (LB) simulations of the convection-diffusion equation in a two-dimensional channel flow with reactive-flux boundary conditions. We compared several different implementations of a zero-concentration boundary condition using the Two-Relaxation-Time (TRT) LB model. We found that simulations using an interpolation of the equilibrium distribution were more stable than those based on Multi-Reflection (MR) boundary conditions. We have extended the interpolation method to include mixed boundary conditions, and tested the accuracy and stability of the simulations over a range of Damköhler and Péclet numbers.

scholarly journals Analytical Solution for Free Vibrations of a Moderately Thick Rectangular Plate

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Ivo Senjanović ◽  
Marko Tomić ◽  
Nikola Vladimir ◽  
Dae Seung Cho
Keyword(s):  
Analytical Solution ◽  
Boundary Conditions ◽  
Thick Plate ◽  
Mixed Boundary ◽  
Separation Of Variables ◽  
Equations Of Motion ◽  
Mixed Boundary Conditions ◽  
Free Vibrations ◽  
Force Displacement ◽  
Good Agreement

In the present thick plate vibration theory, governing equations of force-displacement relations and equilibrium of forces are reduced to the system of three partial differential equations of motion with total deflection, which consists of bending and shear contribution, and angles of rotation as the basic unknown functions. The system is starting one for the application of any analytical or numerical method. Most of the analytical methods deal with those three equations, some of them with two (total and bending deflection), and recently a solution based on one equation related to total deflection has been proposed. In this paper, a system of three equations is reduced to one equation with bending deflection acting as a potential function. Method of separation of variables is applied and analytical solution of differential equation is obtained in closed form. Any combination of boundary conditions can be considered. However, the exact solution of boundary value problem is achieved for a plate with two opposite simply supported edges, while for mixed boundary conditions, an approximate solution is derived. Numerical results of illustrative examples are compared with those known in the literature, and very good agreement is achieved.

Sign in / Sign up

Export Citation Format

Share Document