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error in running the model: "Attempt to evaluate negative power of zero"

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Hi, I got this error when I try to run my model:

Velocity u, Pressure p Attempt to evaluate negative power of zero. - Function: ^ Failed to evaluate temporary symbolic derivative variable. - Variable: epII@VDN$mod.ux - Defined as: (0.5((0.5((((2(((ep12^2)+(ep13^2))+(ep23^2)))+(ep11^2))+(ep22^2))+(ep33^2)))^(-0.5)))(0.5(2ep11)) Failed to evaluate temporary symbolic derivative variable. - Variable: nb@VDN$mod.ux - Defined as: (((0.5((0.5((((2(((ep12^2)+(ep13^2))+(ep23^2)))+(ep11^2))+(ep22^2))+(ep33^2)))^(-0.5)))(0.5(2ep11)))1.4142135623730951)((-(c0-(((fcrho)g)z)))/((epII1.4142135623730951)^2)) Failed to evaluate temporary symbolic derivative variable. - Variable: n@VDN$mod.ux - Defined as: (nT>nb)((((0.5((0.5((((2(((ep12^2)+(ep13^2))+(ep23^2)))+(ep11^2))+(ep22^2))+(ep33^2)))^(-0.5)))(0.5(2ep11)))1.4142135623730951)((-(c0-(((fcrho)g)z)))/((epII1.4142135623730951)^2))) Failed to evaluate temporary symbolic derivative variable. - Variable: mod.spf.mu@VDN$mod.ux - Defined as: (nT>nb)((((0.5((0.5((((2(((ep12^2)+(ep13^2))+(ep23^2)))+(ep11^2))+(ep22^2))+(ep33^2)))^(-0.5)))(0.5(2ep11)))1.4142135623730951)((-(c0-(((fcrho)g)z)))/((epII1.4142135623730951)^2))) Failed to evaluate temporary symbolic derivative variable. - Variable: mod.spf.mu_eff@VDN$mod.ux - Defined as: (nT>nb)((((0.5((0.5((((2(((ep12^2)+(ep13^2))+(ep23^2)))+(ep11^2))+(ep22^2))+(ep33^2)))^(-0.5)))(0.5(2ep11)))1.4142135623730951)((-(c0-(((fcrho)g)z)))/((epII1.4142135623730951)^2))) Failed to evaluate temporary symbolic derivative variable. - Variable: mod.spf.K_stress_tensorxz@VDN$mod.ux - Defined as: (mod.uz+mod.wx)((nT>nb)((((0.5((0.5((((2(((ep12^2)+(ep13^2))+(ep23^2)))+(ep11^2))+(ep22^2))+(ep33^2)))^(-0.5)))(0.5(2ep11)))1.4142135623730951)((-(c0-(((fcrho)g)z)))/((epII1.4142135623730951)^2)))) Failed to evaluate expression. - Expression: dvol(-((mod.uz+mod.wx)((nT>nb)((((0.5((0.5((((2(((ep12^2)+(ep13^2))+(ep23^2)))+(ep11^2))+(ep22^2))+(ep33^2)))^(-0.5)))(0.5(2ep11)))1.4142135623730951)((-(c0-(((fcrho)g)z)))/((epII1.4142135623730951)^2)))))) Failed to evaluate Jacobian of expression. - Expression: dvol(-mod.spf.K_stress_tensorxz) Failed to evaluate Jacobian of expression. - Expression: ((mod.p-mod.spf.K_stress_tensorxx)test(mod.ux)-mod.spf.K_stress_tensorxytest(mod.uy)-mod.spf.K_stress_tensorxztest(mod.uz)-mod.spf.K_stress_tensoryxtest(mod.vx)+(mod.p-mod.spf.K_stress_tensoryy)test(mod.vy)-mod.spf.K_stress_tensoryztest(mod.vz)-mod.spf.K_stress_tensorzxtest(mod.wx)-mod.spf.K_stress_tensorzytest(mod.wy)+(mod.p-mod.spf.K_stress_tensorzz)test(mod.wz))*(dvol)

what can be the issue?

thank you, all the best, V.


0 Replies Last Post Jan 10, 2018, 5:08 a.m. EST
COMSOL Moderator

Hello Vale R.

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