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Modelling Transient Laminar To Turbulent Flowrates

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All,

I've been trying to find workarounds, or an official method, to model a time-dependent heating and flow simulation, where the heating stage has no fluid flowing (<0.1% full flow to help convergence), and then a second stage where the flow ramps from no flow to full flow. This transition ends up with Re values near zero, to Re values well into the Turbulent regime (~9000).

Because of this, I have not found a way to use the turbulent equations for modelling the fluid flow because the first section is completely laminar. I have been able to use laminar to model the full flow regime, but question the accuracy due to lack of factoring in the turbulence into the simulation.

Does anyone know the best way of modelling transition transition from laminar to turbulent conditions effectively?

I have included a simplified test simulation for reference.

Thanks much.



1 Reply Last Post 9 nov 2020, 10:25 GMT-5
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Hello Eric Madsen

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Rogelio Garcia Fernandez Certified Consultant

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Posted: 4 years ago 9 nov 2020, 10:25 GMT-5

Did you come with a solution? I ran to the oposite problem. I want to go from turbulent to laminar.

Did you come with a solution? I ran to the oposite problem. I want to go from turbulent to laminar.

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