| Author | Message | ||
     Yasuo Hira (jun) Member Username: jun Post Number: 9 Registered: 12-2007 |
Dear Mr. Nelson I want to define the variable value near a boundary. Is it possible to define? If possible how can I define it? | ||
| Marek Nelson (mgnelson) Moderator Username: mgnelson Post Number: 86 Registered: 07-2007 |
You can apply boundary conditions only on REGION boundaries or FEATURES. You will have to add another region or a feature in order to apply the value. You can also use a source or sink term in your PDE to drive the variable to the desired value. I should point out that in applying a VALUE condition at a location, this becomes a defacto 'boundary' to the PDE. | ||
| Yasuo Hira (jun) Member Username: jun Post Number: 10 Registered: 12-2007 |
Dear Mr. Nelson What I wrote was not accurate. My problem is to define a boundary condition near certain boundary. Such as Natural(Co2) = -k*Co2,surface Where, Co2 is concentration of oxygenand eCo2,surfacef is concentration of oxygen near boundary. It seems that if I set another region near boundary and define another local oxygen concentration as another variable, such as Co2surface, current version doesnft allow us such definition. In version 6 announcement it is written 'Regionally Inactive Variables -Variables can be declared inactive in some regions and active in others. e. So is it possible to write such way in next version? | ||
| Marek Nelson (mgnelson) Moderator Username: mgnelson Post Number: 87 Registered: 07-2007 |
You can state a boundary condition as NATURAL(Co2) = -k*Co2 The right hand side will be evaluated at the boundary. | ||
| Yasuo Hira (jun) Member Username: jun Post Number: 11 Registered: 12-2007 |
Mr. Nelson Now I could understand well. You mean I can set my boundary condition like above in current version. I appreciate your co-operation. | ||
| Marek Nelson (mgnelson) Moderator Username: mgnelson Post Number: 88 Registered: 07-2007 |
Yes, the above BC is valid in all versions of FlexPDE. I think we were just miscommunicating about the meaning of 'near'. |