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Probleme on the turbulence
Posted 26 feb 2010, 04:19 GMT-5 Version 3.5a 2 Replies
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I'm modeling the impact of a droplet onto a substrate using the level set method . i use the module: two phase flow, laminar, level set.
when I increase the impcat velocity, I added the turbulence model and when I click to solve my problem, I got the message bellow:
Time-dependent solver/Generalized alpha
Number of degrees of freedom solved for: 271446
Step Time Stepsize Res Jac Sol Order Tfail NLfail
0 0 out 3 2 2 0
Error:
Failed to find consistent initial values.
Sqrt_of_negative
Function: sqrt
Failed_to_evaluate_expression
Expression: nojac(((min((ck_chns*sqrt((((taum_chns*res_v_chns)^2)+((((res_p_chns*tauc_chns)/(nojac(sqrt((u2int_g1_chns/vol_g1_chns)))*nojac((rhoint_g1_chns/vol_g1_chns)))))^2+((taum_chns*res_u_chns))^2)))),U_ref_chns)*0.5)*min((gijgij_chns^-0.25),((rho_chns*U_ref_chns)/((etaT_chns+eta_chns)*48)))))
Failed_to_evaluate_symbolic_derivative_variable
Variable: shock_capt_chns@VDN${test@3}, Defined_as: ((r*(rho_chns*(-nojac(((min((ck_chns*sqrt((((taum_chns*res_v_chns)^2)+((((res_p_chns*tauc_chns)/(nojac(sqrt((u2int_g1_chns/vol_g1_chns)))*nojac((rhoint_g1_chns/vol_g1_chns)))))^2+((taum_chns*res_u_chns))^2)))),U_ref_chns)*0.5)*min((gijgij_chns^-0.25),((rho_chns*U_ref_chns)/((etaT_chns+eta_chns)*48))))))))*((ur*g21_chns)+(uz*g22_chns)))
Failed_to_evaluate_expression
Expression: d(((r*(-2*(eta_chns+etaT_chns)*ur+p)*test(ur)-r*(eta_chns+etaT_chns)*(uz+vr)*test(uz)+(-r*rho_chns*(u*ur+v*uz)-2*(eta_chns+etaT_chns)*u/r+p)*test(u)+gls_chns+shock_capt_chns)-(r*rho_chns*ut*test(u)))*(dvol),{test@3})
if someone could tell me on how to solve this probleme I will really appreciate.
best regards
Hello Soufiane Oukach
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