Learning Forum

[Anadi_Mondal]

Hello,

Here is the description of the model

1) The simulation is to visualize Annular flow in tube. I choose Eulerian -Eulerian model with water as primary phase and vapor as secondary phase. Vapor will flow inside the core of tube and liquid as film at wall. Moreover, I am using DPM to inject liquid droplet from the interior_surface(please see attached mesh). Will this interior surface create blockage to flow liquid/vapor in tube?

2) Only vapor is flowing from the inlet (keep the volume fraction 0 under multiphase tab, if I keep 0 here I am getting residuals for water and for 1 ,getting residuals for vapor only) and I am using a injection wall (EWF) near inlet for liquid film. Here I have added a mass flux(water)

3) I enable Eulerian Wall Film at injection wall, stabilization and annular wall under boundary conditions and finally initialize EWF from Model(Eulerian Wall Film)

The simulation is running but giving residuals only for water or vapor ,not water and vapor together.

Would you tell me where is the mistake?

Thank You

Anadi

[Rob]

Eulerian-Eulerian is multiphase model, and mass won't transfer from DPM without an additional mechanism which you don't have in the model: you don't want it either. nRead the background on the EWF, that'll explain why you're not seeing any equations for the film. Yes, it's an Euler model but it's NOT linked to the above multiphase model. n

[Anadi_Mondal]

Sorry I did a mistake The simulation includes a two-dimensional Eulerian liquid film model coupled to a three-dimensional core model (including vapor flow and droplets) based on the Eulerian – Lagrangian approachnThe liquid film should be simulated as a two-dimensional Eulerian model while the vapor-droplets model should be simulated as a three-dimensional Eulerian – Lagrangian model, both models are simultaneously coupled.nNow do you have any suggestion?

[Anadi_Mondal]

nI am going over the background of EWF and DPM from manual again. But before that I have a quick question-As liquid film should be simulated as a two-dimensional Eulerian model while the vapor-droplets model should be simulated as a three-dimensional Eulerian ? Lagrangian model, both models are simultaneously coupled, how can I confirm them? In the EWF ,there is an option to select 'film material'(I selected water liquid) but in DPM ,how can I confirm that the continuous phase is vapor here ? For dispersed phase in core(vapor) is liquid droplets that I can set by changing inert particle properties (same as liquid).nAnadin

[Rob]

You set the carrier fluid as normal, and then set the wall film & droplets to be the same material. Play around with the settings, 2021R1 will tell you if it' doesn't like the setting you used. n