Reply To: Undesired velocity at corner when changing the contact angle in free energy
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Are you by any chance using different values for kappa1 and kappa2? If so then this might be the cause. The reason is that if the value h1/kappa1 + h2/kappa2 != 0 then the density on the solid boundary will be different. This will then interact with the outlet causing it to become unstable.
To find the correct kappa values you can use the formula gamma = alpha/6 * (kappa1 + kappa2), where gamma is the surface tension converted into lattice units. Since you are only using two components you can therefore set kappa1 = kappa2 = 3*gamma/alpha.
Unfortunately by changing the kappa values you will also change the contact angles, so you may need to recompute the values h1 and h2.
If this isn’t the issue then please do let me know.