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: Attempt to evaluate negative power of zero.
Posted 29.06.2011, 22:33 GMT-4 Modeling Tools & Definitions, Parameters, Variables, & Functions Version 5.2 1 Reply
Please login with a confirmed email address before reporting spam
I'm faced with this error when solving my time-dependent problem:
Attempt to evaluate negative power of zero.
- Function: ^
Failed to evaluate temporary symbolic derivative variable.
- Variable: Ve_r@VDN${abs@5}
- Defined as: ((sign(mod1.es.Er)*(-60.600000000000001))*(0.75*(abs((0.01*mod1.es.Er))^(-0.25))))
Failed to evaluate temporary symbolic derivative variable.
- Variable: mod1.cd2.u@VDN${abs@5}
- Defined as: (((sign(mod1.es.Er)*(-60.600000000000001))*(0.75*(abs((0.01*mod1.es.Er))^(-0.25)))))
Failed to evaluate expression.
- Expression: d(mod1.cd2.u,{abs@5})
Failed to evaluate operator Jacobian.
- Operator: mean
Can anyone help?
Thanks
Hello Imran Ibrahim
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.
Please login with a confirmed email address before reporting spam
i try to module the electricall double layer, using electrostatic et transport of diluted species module but I cannot successfully implement the surface charge in boundary condition and i had the same problem and it seem the same msg error :
Attempt to evaluate negative power of zero.
- Function: ^
Failed to evaluate temporary symbolic derivative variable.
- Variable: comp1.Surf_Charge_Density@VDN$comp1.phi
- Defined as: (((comp1.CONST7^(-0.5))*0.5)*((-((-(((((exp((-comp1.phi)/V_therm)*(-(1/V_therm)))*cA_bulk)*CONST1)*a3)*comp1.CONST3))*(1/(1-(comp1.CONST3*(a3*comp1.NS_positif))))))*CONST2))*e_const
Failed to evaluate temporary symbolic derivative variable.
- Variable: comp1.es.sfcd1.rhoqs@VDN$comp1.phi
- Defined as: (((comp1.CONST7^(-0.5))*0.5)*((-((-(((((exp((-comp1.phi)/V_therm)*(-(1/V_therm)))*cA_bulk)*CONST1)*a3)*comp1.CONST3))*(1/(1-(comp1.CONST3*(a3*comp1.NS_positif))))))*CONST2))*e_const
Failed to evaluate expression.
- Expression: ((-((((comp1.CONST7^(-0.5))*0.5)*((-((-(((((exp((-comp1.phi)/V_therm)*(-(1/V_therm)))*cA_bulk)*CONST1)*a3)*comp1.CONST3))*(1/(1-(comp1.CONST3*(a3*comp1.NS_positif))))))*CONST2))*e_const))*comp1.es.d)*dvol
Failed to evaluate Jacobian of expression.
- Expression: (comp1.es.d*(-comp1.es.sfcd1.rhoqs))*dvol
Failed to evaluate Jacobian of expression.
- Expression: (-comp1.es.sfcd1.rhoqs*test(comp1.phi)*comp1.es.d)*(dvol)
- Feature: Stationary Solver 1 (sol3/s1)
so please did you find a solution and how can i fix it
Appreciate much for your help!!