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Reply To: wetting with free surface or large density ratio

OpenLB – Open Source Lattice Boltzmann Code Forums on OpenLB General Topics wetting with free surface or large density ratio Reply To: wetting with free surface or large density ratio


Thank you for your answer @mathias. I am tempted to ask another question then: Let’s take again the example of “ShanChenForcedSingleComponentPostProcessor” if we look at the end of this function it seems that the content of the FORCE field is purely overridden by the EXTERNAL_FORCE field + the additional Shan-Chen model’s term :

auto force = cell.template getField<descriptors::EXTERNAL_FORCE>();
cell.template setField<descriptors::FORCE>(force – g*rhoContribution/rho);

But what if somewhere else on the application the FORCE field is used? I assume that the application developper will have to re-write this portion of code then.

Also, if I look at the forcing.h file, all the forcing schemes seems to take the FORCE field into account but none takes the EXTERNAL_FORCE. Which leads me to think that if an application developer wants to use the EXTERNAL_FORCE field he/she either has to override the FORCE field the same way “ShanChenForcedSingleComponentPostProcessor” does or to re-write and adapt a forcing scheme, is that correct?

Sorry for this basic questions but the concept of EXTERNAL_FORCE Vs FORCE is puzzling. For example, the user manual only mentions the FORCE field and in quite general examples (no mention of the surface tension I believe).

Thanks again, I believe this discussion already provided me enough understanding to implement the Huang et al liquid/fluid interaction force.