Laminar flow around cylinder

sasanghomi · October 14, 2018, 06:22

Dear friends,

I am modeling the fluid flow around a cylinder with Reynolds number of 4.9E3.
According to theoretical books (experimental results), the flow is supposed to be laminar. So, I chose laminar as a turbulence model.
First question: Is it a right job to choose laminar model even though the flow encompasses vortexes?
Also, I am about to calculate heat transfer convection around the cylinder and I have serious convergence problems especially when it comes to the
the imbalance of energy equation.
By the way, the grid is refined perfectly and the range of Y+ in below 2.

Any idea for better convergence? Any hints?

I do appreciate your attention.

Best Regards

subhankarnits · October 14, 2018, 06:27

From what point of view you can say that the flow is laminar?

sasanghomi · October 14, 2018, 11:09

I need to make a comparison between numerical results and the empirical correlations.
Which types of simulation can generate better results for this Reynolds number? Laminar or Turbulent?

ghorrocks · October 14, 2018, 17:55

I answered this same question in your other thread: Convective Heat Transfer Coefficient (Flow over cylinder)

Please continue discussion on this topic on the other thread.

October 14, 2018, 06:22	Laminar flow around cylinder	#1
sasanghomi Senior Member Sasan Ghomi Join Date: Sep 2012 Location: Denmark Posts: 292 Rep Power: 14	Dear friends, I am modeling the fluid flow around a cylinder with Reynolds number of 4.9E3. According to theoretical books (experimental results), the flow is supposed to be laminar. So, I chose laminar as a turbulence model. First question: Is it a right job to choose laminar model even though the flow encompasses vortexes? Also, I am about to calculate heat transfer convection around the cylinder and I have serious convergence problems especially when it comes to the the imbalance of energy equation. By the way, the grid is refined perfectly and the range of Y+ in below 2. Any idea for better convergence? Any hints? I do appreciate your attention. Best Regards

October 14, 2018, 17:55		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	I answered this same question in your other thread: Convective Heat Transfer Coefficient (Flow over cylinder) Please continue discussion on this topic on the other thread. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

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October 14, 2018, 06:27		#2
subhankarnits Member subhankar das Join Date: Jul 2018 Posts: 32 Rep Power: 7	From what point of view you can say that the flow is laminar?

October 14, 2018, 11:09		#3
sasanghomi Senior Member Sasan Ghomi Join Date: Sep 2012 Location: Denmark Posts: 292 Rep Power: 14	I need to make a comparison between numerical results and the empirical correlations. Which types of simulation can generate better results for this Reynolds number? Laminar or Turbulent?