Hello,

I was trying to represent the weak formula of the following system of reaction diffusion equations

Where the main variables Cm and Ce are the ester and monomer concentrations as you can see in the fórmula. The parameters K1, Ce and alpha are known (0.1 and 1 respectively)-

The boundary conditions are Cm =0 in the free surface and Ce=exp(-k1)*t, which is a Dirchlet time dependent condition, in the same boundary(the second boundary condition was obtained by integrating the second equation of the system,substituting Cm by 0).

The initial conditions are Cm=0 and Ce=1.

I tried to derive the weak form of the two equations by multiplying them by thier respective test functions (v and w) and making the correspondent transformations.

problem reactiondiffusion(Cmn,Cen,v,w)=

int3d(Th,optimize=0)((Cmn/dt)*v)

+int3d(Th,optimize=0)((Cen/dt)*v)

+int3d(Th,optimize=0)(f*grad(Cmn)’*grad(v))

-int3d(Th,optimize=0)((b+Cmnold/dt)*v)
-int3d(Th,optimize=0)((-b+Cenold/dt) w)
//-int3d(Th,optimize=0)(1e-20Cen*w)//Stabilization term

+on(Free, Cmn=0, Cen=g);

However once I execute the code i found the following error

On return from DMUMPS, INFOG(1)= -9

On return from DMUMPS, INFOG(2)= 2076104

Erreur Mumps seq: number -9

Fatal Erreur MUMPS_seq Factorize

Entering DMUMPS 5.0.2 driver with JOB, N, NZ = -2 31200 874536

current line = 78

Exec error : MUMPS_seq Factorize

– number :0

– MUMPS solve, peak Mem : 242 Mb, n = 31200 sym =0 trans = 0

** Instance Error 1 in DMUMPS_F77 1

** MPI_ABORT called.

Attached you have the edp code and the mesh fileReaction diffusion_2.edp (1.7 KB)

Model 1_2.mesh (3.3 MB)

. I hope someone can find the solution of the example

Thank you very much in advance

Best Regards

Jacob