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Defining a barycenter velocity in the model

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Hi all I am using fluid-structure-interaction(fsi) interface to simulate a microfludic device,which allows cells flowing through the channel.

As the length of the channel is not very important for my simulation(what is important for my simulation is the final steady-state of cell), I want to keep the cell in the center of the fluid domain.

I read some paper which define a barycenter cell velocity, so movement of all quantities (fluid, cell) is considered to relative to the barycenter velocity.

The problem is that this barycenter velocity should be a time-dependent velocity calculated from each step and cannot be pre-defined. Can anybody give me some clues on how to define a barycenter velocity of cell?


1 Reply Last Post 8 févr. 2019, 07:31 UTC−5

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Posted: 5 years ago 8 févr. 2019, 07:31 UTC−5

All the reference systems, Hittorff, barycentric, Fickian are essentially the same unless the solute concentrations are very high, of the molality order of > 1. I would not expect too much error in your calculations if you just use the solvent velocity as the reference (= Hittorff reference). All the transport quantities are actually defined (and thus measured) in the Hittorff reference frame.

Lasse

All the reference systems, Hittorff, barycentric, Fickian are essentially the same unless the solute concentrations are very high, of the molality order of > 1. I would not expect too much error in your calculations if you just use the solvent velocity as the reference (= Hittorff reference). All the transport quantities are actually defined (and thus measured) in the Hittorff reference frame. Lasse

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