Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Error: Failed to find a solution. Segregated Step 1 System matrix is zero.

Please login with a confirmed email address before reporting spam

I am trying to run a simulation on the below MEMS heater simulation to obtain a surface temperature graph. Upon running a stationary study with default configurations. I get the following error.

// Failed to find a solution. Segregated Step 1 System matrix is zero. In Segregated Step 1: Returned solution is not converged. Not all parameter steps returned. //

In the logs I find this. // Time: 31 s. Physical memory: 3.32 GB Virtual memory: 4.65 GB Ended at 13-Feb-2019 15:58:55. ----- Compile Equations: Stationary in Study 1/Solution 1 (sol1) --------------> <---- Stationary Solver 1 in Study 1/Solution 1 (sol1) ------------------------- Started at 13-Feb-2019 15:59:02. Segregated solver Segregated Step 2 does not have any components solved for. Number of degrees of freedom solved for: 3683168. Segregated solver iteration 1. Segregated Step 1 Symmetric matrices found. Scales for dependent variables: Electric potential (comp1.V): 1 Orthonormal null-space function used. Solution time: 13 s. Physical memory: 3.76 GB Virtual memory: 5.27 GB Ended at 13-Feb-2019 15:59:15.

----- Stationary Solver 1 in Study 1/Solution 1 (sol1) ------------------------>

<---- Compile Equations: Stationary in Study 1/Solution 1 (sol1) --------------- Started at 13-Feb-2019 16:03:49. Geometry shape order: Quadratic Running on Intel64 Family 6 Model 42 Stepping 7, GenuineIntel. Using 1 socket with 4 cores in total on ROMAN. Available memory: 8.15 GB. Time: 30 s. Physical memory: 3.15 GB Virtual memory: 4.48 GB Ended at 13-Feb-2019 16:04:19. ----- Compile Equations: Stationary in Study 1/Solution 1 (sol1) --------------> <---- Stationary Solver 1 in Study 1/Solution 1 (sol1) ------------------------- Started at 13-Feb-2019 16:04:25. Segregated solver Segregated Step 2 does not have any components solved for. Number of degrees of freedom solved for: 3683168. Segregated solver iteration 1. Segregated Step 1 Symmetric matrices found. Scales for dependent variables: Electric potential (comp1.V): 1 Orthonormal null-space function used. Solution time: 12 s. Physical memory: 3.66 GB Virtual memory: 5.02 GB Ended at 13-Feb-2019 16:04:37. ----- Stationary Solver 1 in Study 1/Solution 1 (sol1) ------------------------> //

Physics models used heat transfers in solids(ht), Electric currents(ec). Structure a semiconductor Si/SiO2/SiN/SiO2/ Pt heater electrodes. Bias applied 5V and 0V to either sides of the heater element.

The default solver doesnot have one of the dependent variables (inverse time step measure) added in either segregated step 1 or step 2 of the stationary solver. Adding it to step 1 hasn't helped with the solution either. I've seen that the Direct solver uses a MUMPS and Iterative used conjugate gradients. Tried using other methods but that doesn't seem to be the problem.

Any leads on how to go about solving the error would be much appreciated! Attached the solver panel and structure images for your reference.

-------------------
AT


0 Replies Last Post 13 févr. 2019, 16:22 UTC−5
COMSOL Moderator

Hello atannee

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.