Dimensional analysis / similarity analysis help

AI Thread Summary
The discussion focuses on simulating gas diffusion and ventilation in a scaled-down enclosure using smoke pellets for visualization. The user questions whether the velocity of a fan used to simulate wind needs to be adjusted for the 1/10 scale model. It is noted that the convective mass transfer term in the mass transfer differential equation is dependent on velocity, indicating that scaling is necessary. The user seeks guidance on the appropriate parameters for this analysis. Overall, the conversation emphasizes the importance of dimensional analysis in fluid motion simulations.
victor_123
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I’m currently investigation the fluid motion (diffusion) of gas's so see how well they can ventilate in an enclosure.

I would like to simulate this using a (1/10) scale model. The enclosure has already been built, and smoke pellets are going to be placed inside to help visualize fluid motion.

If I add a fan to simulate wind, will there have to be any scaling on its velocity to account for the 1-10 scale model and smoke pellets being used??

Any help or opinions are greatly appreciated

Thanks
 
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I think so. If you have a model race track then a car traveling normal speeds on your scaled down track would be way too fast, right?

The mass transfer differential equation...
∂CA/∂t + v.∇CA = DAB2CA

Where v.∇CA is your convective mass transfer term and, as you can see, is entirely dependent on velocity.
 
Thanks, that’s what I thought too. But I’m unsure of what parameters to use in the analysis. Any ideas people?

Thanks again
 
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