[thj]

Hello together,

I'm trying to model a 3D volumetric Goldak heat source that is moving over a simple steel plate.
The problem I’m facing is that the simulation stops after a short amount of iterations (about 0.2s simulated time). I used an expression for thermal expansion and phase density difference buoyancy forces, the Kozeny-carman permeability model with min/max clipping. The setup is shown in the attached pictures. The used CEL expressions are :


LIBRARY:
CEL:
EXPRESSIONS:
BetaLiq = 4.2333e-05[K^-1]
BuoySrcRho = ((LiqFrac*rhoL+(1-LiqFrac)*rhoS)-rhoRef)*g
BuoySrcT = -BetaLiq*rhoL*(T-Tref)*LiqFrac*g
Kperm = Kstar*(1-LiqFrac)^2/max(LiqFrac^3, 1e-10)
Kperm2 = max(min(KpermMax,Kperm), 1e-15 [m^-2])
KpermMax = 1.0E+9[kg s^-1 m^-3] / Visc
Kstar = 1e10[m^-2]
L = 246800[J/kg]
LiqFrac = Liquid Steel.Mass Fraction
PL = 2400[W]
Q = if(qf1*qf+qr1*qr<=0[kg m^-1 s^-3],1[kg m^-1 s^-3],qf1*qf+qr1*qr)
Tcold = 1700[K]
Thot = 1800[K]
Tmelt = 1800[K]
Tref = Tcold
Visc = Liquid Steel.Dynamic Viscosity
a = 0.004[m]
b = 0.005[m]
cf = 0.0025[m]
cr = 0.0075[m]
ff = 0.5
fr = 1.5
kf = (6*sqrt(3)*ff*PL)/(a*b*cf*pi*sqrt(pi))
kr = (6*sqrt(3)*fr*PL)/(a*b*cr*pi*sqrt(pi))
qf = kf*exp(-3*((x-vl*t)^2/cf^2+y^2/a^2+z^2/b^2))
qf1 = if(x>vl*t,1,0)
qr = kr*exp(-3*((x-vl*t)^2/cr^2+y^2/a^2+z^2/b^2))
qr1 = if(x<vl*t,1,0)
rhoL = Liquid Steel.Density
rhoRef = rhoS
rhoS = 7854[kg/m^3]
vl = 0.005[m s^-1]
END
END


Something is wrong with this model, but I don’t know what it is.
Maybe someone has a clue what is wrong with the simulation.

Best regards
Joe T.

[thj]

More setup details

[thj]

More details on the run...

[thj]

Finally the last screenshots are about to arrive

[ghorrocks]

CFX does not have a melting model, so of course it cannot do this.

What are you trying to do here? Why are you doing this? Modelling welding is very complex and difficult and CFX is not ideal for it. But depending on what you are trying to achieve you might be able to do it in CFX.

[evcelica]

Just one comment: You seem to have the same reference enthalpy and point for each phase. Meaning your latent heat of melting is zero, unless you defined it elsewhere?