ddt (rho U) + div (rho U U) – laplacian (mu U) = – grad (p)
Sometimes, implementing time varying boundary conditions for a transient simulation is interesting. A series of pressure (or other varibles) values should be read from a text file, and update the boundary at each timestep. the boundary scalar value type should Continue reading Transient Boundary Syntax Changed in OpenFOAM v1.5
Valid ddt schemes are : ( CoEuler boundedBackward SLTS CrankNicholson steadyState Euler backward ) The format style for ddtScheme is: ddtScheme { default Euler; } for CrankNicholson, it is: default CrankNicholson 1; where, 1 represents the scheme is Continue reading Discrete Schemes in OpenFOAM
OpenCFD has announced a new version of OpenFOAM, version 1.5 on July 14, 2008. The new version has some major changes, such as a lot of new and demonstration applications with examples, a new mesh utility including cell layer insertion, Continue reading OpenFOAM 1.5 Released
Generally, in the explicit schemes of differential method, Courant number is an important number which should be less than 1 in order to assure the stability. However, if the Courant number is too small, much computation time will be lost. Continue reading Run a Case with Variable Time Step in OpenFOAM
Linear Equation Systems are most concerned in modern scientific and engineering computation, because most problems can be described by (partial) differential equations which could be discretized to a system of algebraic equations which can be solved on a computer. There Continue reading Solutions of Linear Equation Systems Used in OpenFOAM
In OpenFOAM, We can simulate fluid dynamics with general meshes, such as tetrahedral, hexhedral, and with polyhedral mesh which workes well in OpenFOAM. Generally, A tetrahedral mesh in a geometric model should be done, which should be converted to the Continue reading How to convert tetrahedral mesh to polyhedral mesh