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model crashed by Failed to evaluate temporary symbolic derivative variable
Posted 3 oct. 2018, 17:02 UTC−4 Fluid & Heat, Computational Fluid Dynamics (CFD), Heat Transfer, Porous Media Flow Version 5.3 0 Replies
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Hi there,
I used the two coupled PDEs (one is for moisture flow and another one is heat transfer) to simulate water flow, heat transfer and phase change in the frozen soil. At the beginning, the simulation is running good, but finally crashed.
BTW, the volumetric water (comp1.w) fluctuated all the time. It is some strange.....
Could you give me some suggestions to deal with below errors? Thanks you very much!
Repeated error test failures. May have reached a singularity.
Time : 55472.39531547238
Attempt to evaluate nonintegral power of negative number.
Function: ^
Failed to evaluate temporary symbolic derivative variable.
Variable: comp1.faVDN$comp1.w, Defined as: (((1/(selt m-selt n))(((-1)/m)((comp1.Sr+eps)^(((-1)/m)-1))))((1/n)((eps+((-1)+((comp1.Sr+eps)^((-1)/m))))^((1/n)-1))))*(1/a0)
Failed to evaluate expression.
Expression: d((-(comp1.wt+roh id(comp1.selt ice,t)unit s cf/(roh wunit m cf^2))test(comp1.w)-comp1.kunit s cf(1+d(comp1.fa,comp1.w)comp1.wx)test(comp1.wx)/unit m cf^2-comp1.kunit s cf(1+d(comp1.fa,comp1.w)comp1.wy)test(comp1.wy)/unit m cf^2)*(dvol spatial),{test10})
Failed to evaluate Jacobian of expression. Expression: (-(comp1.wt+roh id(comp1.selt ice,t)unit s cf/(roh wunit m cf^2))test(comp1.w)-comp1.kunit s cf(1+d(comp1.fa,comp1.w)comp1.wx)test(comp1.wx)/unit m cf^2-comp1.kunit s cf(1+d(comp1.fa,comp1.w)comp1.wy)test(comp1.wy)/unit m cf^2)*(dvol spatial)
Attempt to evaluate nonintegral power of negative number. Function: ^
Failed to evaluate temporary symbolic derivative variable. Variable: comp1.faVDN$comp1.w, Defined as: (((1/(selt m-selt n))(((-1)/m)((comp1.Sr+eps)^(((-1)/m)-1))))((1/n)((eps+((-1)+((comp1.Sr+eps)^((-1)/m))))^((1/n)-1))))*(1/a0)
Failed to evaluate expression. Expression: d((-(comp1.wt+roh id(comp1.selt ice,t)unit s cf/(roh wunit m cf^2))test(comp1.w)-comp1.kunit s cf(1+d(comp1.fa,comp1.w)comp1.wx)test(comp1.wx)/unit m cf^2-comp1.kunit s cf(1+d(comp1.fa,comp1.w)comp1.wy)test(comp1.wy)/unit m cf^2)*(dvol spatial),{test10})
Failed to evaluate Jacobian of expression. Expression: (-(comp1.wt+roh id(comp1.selt ice,t)unit s cf/(roh wunit m cf^2))test(comp1.w)-comp1.kunit s cf(1+d(comp1.fa,comp1.w)comp1.wx)test(comp1.wx)/unit m cf^2-comp1.kunit s cf(1+d(comp1.fa,comp1.w)comp1.wy)test(comp1.wy)/unit m cf^2)*(dvol spatial)
Last time step is not converged.
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Hello xiao huang
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