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Error in user-defined Analytic function
Posted 07.02.2024, 00:42 GMT-5 0 Replies
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Well, I have been trying to solve a Partial differential equation using Coefficient form PDE interface. And after setting up everything and solving, I am getting an error saying this
Error in user-defined function. Function: dtPa Failed to evaluate expression. Expression: dvol spatial(-(comp1.Pat-dtPa(comp1.T,comp1.Pa))) Failed to evaluate Jacobian of expression. Expression: (-(comp1.Pat-dtPa(comp1.T,comp1.Pa))test(comp1.Pa))*(dvol spatial) Last time step is not converged.
Well, basically I understood that the issue with the function 'dtPa' it is analytical function defined by me as it is one of the important terms in my PDE. But, I am not able to find any error. This is the expression used for the definition. Maybe someone can solve the Issue.
if(T > T_rA , -A_Arho_Av ( ( (Pa - rho_Ac)/rho_Av )^3 ) * exp( -E_A/T ), 0)
My function, kind of is a piecewise function. I had to use an if condition instead of piecewise function in Comsol as my function more than 1 argument.
T, Pa are dependent variables in my PDE
T_rA, A_A, rho_Av, rho_Ac, E_A are constants defined in workspace already.
Hello Kandibanda N Venkata Chandra Sekhar Guptha
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