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How to specify different boundaries in an equation
Posted 2012年3月30日 GMT-4 16:06 Version 4.3b 5 Replies
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There are two boundaries in my model: Boundary A and Boundary B. Boundary A is located at x = 0 cm, while Boundary B is located x = 2 cm. There is an equation which is a boundary condition:
-q*(∇u2) = 1.5* (u(A)-u5(B)-E(B))/(q*R)
Where A and B refer to Boundary A and Boundary B. u, u2 and u5 are the electric potential of electrons, iodide ions and the electrostatic potential, respectively.
My question is: how do I specify these two boundaries in this equation of boundary condition? How do I tell the computer that I want to use the value of u at Boundary A and the values of u5 and E at boundary B? I try to type this as the "g" value of the Neumann boundary condition:
1.5* (u(x=0)-u5(x=2)-E(x=2))/(q*R)
but it doesn't work.
Thank you!
-q*(∇u2) = 1.5* (u(A)-u5(B)-E(B))/(q*R)
Where A and B refer to Boundary A and Boundary B. u, u2 and u5 are the electric potential of electrons, iodide ions and the electrostatic potential, respectively.
My question is: how do I specify these two boundaries in this equation of boundary condition? How do I tell the computer that I want to use the value of u at Boundary A and the values of u5 and E at boundary B? I try to type this as the "g" value of the Neumann boundary condition:
1.5* (u(x=0)-u5(x=2)-E(x=2))/(q*R)
but it doesn't work.
Thank you!
5 Replies Last Post 2013年11月16日 GMT-5 18:22