Lagrangian bubble column
 

Hello!
Im trying to do a particle user fortran routine to calculate the added mass coefficient and to do so , I need to find the distance between the particles and the acceleration of each particle.

If you guys can help me with this, it would be much appreciated !
Thank you

Is this a eularian or lagrangian particle tracking model?

The distance would be calculated the same regardless of the model - you can work back from the volume fraction and particle size how many particles per unit volume and therefore their average distance apart. Important note - in lagrangian particle tracking models the tracked particles are representative of a population of particles. In other words, there are more particles than is modelled in the particle tracks.

Acceleration is a bit more tricky. I guess if this is lagrangian you can double differentiate the particle position to get the acceleration. I would need to do some thinking to determine this for Eularian models.

It's for a lagrangian model

OK, thanks. Do my suggestions help?

The thing is , my professor asked me to isolate 3 air bubbles (in air bubble column) and use the equations to calculate the added mass force that require the distance between the bubble 1 and 2 , the bubble 1 and 3 and also the acceleration of each of those bubbles. I'm not familiar with fortran user routine. If you guide me, that would be appreciated.

The CFX documentation has several examples of user fortran. There are more on the ANSYS Customer website.