Pressure drop across a filter medium vs. time modelling

AI Thread Summary
The discussion centers on modeling the dynamic pressure drop across a filter medium in computational fluid dynamics. The user seeks to adapt existing equations, such as Kozeny-Carman and Ergun, which do not account for time, to a dynamic framework while using a constant flow rate. A response suggests that the dynamic aspect may be less critical, as the pressure drop is primarily influenced by viscous drag, allowing for the use of steady-state equations. It emphasizes the importance of considering the buildup of the filter cake in the modeling process. Overall, the focus is on finding a practical approach to incorporate time effects in pressure drop modeling.
slayomer
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Hello guys, I am a computer science PhD student. But my project somehow requires some knowledge about computational fluid dynamic modelling (both discrete and continuous). nowadays I am abit stucked in an issue. I want to model pressure drop across a filter medium dynamically. i assume i have every parameter like flowrate, cake thickness, viscosity of suspension, particle diameter, solid ratio (concentration) etc. I know kozeny-carman, ergun, or endo equations used for pressure drop modelling. but they are not dynamic. time information is not included in the equations. how could the formulas converted to dynamic version if the experiments are done with CONSTANT flow rate pump. Any help with this greatly appreciated, thanks.
 
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slayomer said:
Hello guys, I am a computer science PhD student. But my project somehow requires some knowledge about computational fluid dynamic modelling (both discrete and continuous). nowadays I am abit stucked in an issue. I want to model pressure drop across a filter medium dynamically. i assume i have every parameter like flowrate, cake thickness, viscosity of suspension, particle diameter, solid ratio (concentration) etc. I know kozeny-carman, ergun, or endo equations used for pressure drop modelling. but they are not dynamic. time information is not included in the equations. how could the formulas converted to dynamic version if the experiments are done with CONSTANT flow rate pump. Any help with this greatly appreciated, thanks.
Hi slayomer! Welcome to Physics Forums!
The dynamic part is not going to be important, because the pressure drop-flow rate behavior is going to be dominated by viscous drag. So just use the steady state versions (i.e., assume instantaneous steady state). Of course you have to take into account the buildup of the filter cake.

Chet
 
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