trying to simulate coalescence of two water droplets

[CKJK]

Hello all,

I am trying to simulate two spheres coalescence process. I gave two spheres the same properties: density and elasticity. I made the step dynamic/explicit, and gave velocities in predefined field. I made their surfaces have surface contact interaction, and made their element type explicit 3D stress.

However, they seemed to collide apart instead of coalescent together. But I do not know what parameter I should modify to achieve what I expect. Hope someone can take a look at what I have simulated, and give a suggestion or provide some related tutorials to watch~

I attached my animation video and original file here~

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/video/upload/v1596311371/tips/Abaqus_CAE_Student_Edition_2019_-_Model_Database__D__SURA_ABAQUS_test_load_on_sphere.cae_Viewport__1_2020-08-01_15-47-25_Trim_lepln0.mp4[/url]

Thanks a lot in advance!!

 

[FEA way]

In my opinion, that’s something that should be modeled using CFD. But if you want to do it in Abaqus and treat droplets as solids, you need proper material data and velocities so that these two spheres coalesce after impact. You may also have to adjust contact properties.

 

[IceBreakerSours]

What is the physical problem you are trying to tackle?

You need to assign some sort of stickiness to the interaction. I haven't used Abaqus in a while so I may be mistaken but, if I recall correctly, Abaqus offers an option somewhere that says something like "no separation". However, all it does is glue two entities together once the contact solver detects two entities are "close enough" based on some predefined tolerance.

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[FEA way]

Surface-based cohesive behavior could work too. It can be used to model sticky contact.

 

[CKJK]

Thanks guys! I tried cohesive behavior option, but it does not allow contact pair interactions, since I have two parts, how can I use cohesive behavior?