[wuming]

hi all!
I want to use a porous medium to simulate a gas-liquid-solid three-phase trickle bed.
I use UDF to describe the momentum exchange coefficient.gas-solid and liquid-solid are setting in zone conditions by source term.gas-liquid are add to phase interaction.but the result is wrong, the pressure is too low.Part of the UDF content and exchange coefficienas are follows:



GS[SIZE="<font style="vertical-align: inherit;"><font style="vertical-align: inherit;">1</font></font>"][/SIZE]
rho_g = 1.225;
mu_g = 1.7894e-05;
E1 = 180;
E2 = 1.8;
cta = C_UDMI(cell, t, 0);
cgmb = 1 - void_g * cta;
a = (1 - cta) / cgmb;
b = void_g * cta;
Ags = 180 * pow(cgmb, 2)*pow(a, 0.66667) / b / b / pow(0.0016, 2);
Bgs = 1.8 * cgmb*pow(a, 0.33333) / b / b / 0.0016;
source = -(Ags * mu_g*y_vel_g + Bgs * rho_g*fabs(y_vel_g)*y_vel_g) - Fvol;
dS[eqn] = -0.8* (Ags * mu_g + 2 * Bgs * rho_g*y_vel_g );
return source;

[wuming]

please help me