[Hong M.H]

Hello guys, currently i am doing a simulation regarding the mixing between two fluids in a mixing channel. I am validating my model against an experimental work. The case is in 3D and i am using laminar model. In addition, i m using species transport model for the mixture. However, for my simulation cases, it failed to capture those swirling flow that can be observed from the experimental work. is there any solution or setting which can help me to capture those swirling flow in my visualization result? The visualization results are attached as below: top (present simulation), bottom (experimental work)

Capture.JPG

Capture1.JPG

[RaiderDoctor]

Hi, those look like some really great results. Can I ask what the total simulation end time is? You may simply not be calculating long enough to fully capture the swirling.

[Hong M.H]

Originally Posted by RaiderDoctor

Hi, those look like some really great results. Can I ask what the total simulation end time is? You may simply not be calculating long enough to fully capture the swirling.

Hello, Mr. RaiderDoctor. In my simulation case, the exact end time is depending on the mixing degree between the two fluids. Once it becomes constant, i will start to output the visualization results and data. Besides, i assumed the flow inside the channel is fully developed as the velocity profile across the plane (perpendicular to the flow direction) is constant. Maybe i should extend the simulation time as the mixing between two fluids might not fully developing throughout the whole 3D model. Thanks for the precious advice.

[RaiderDoctor]

I haven’t really worked with mixtures all that much, but the final output reminds me of flow over a cylinder. Hence why I asked about the simulation time. I understand that after a certain time the values will reach an equilibrium, I’m just curious to see if you had simulated long enough passed that point. That way, the swirls would have enough time to propagate down the channel.
Try to check this thread to see if it helps at all (Flow over circular cylinder). Again, I could be totally wrong, but where’s the harm?

[Hong M.H]

Originally Posted by RaiderDoctor

I haven’t really worked with mixtures all that much, but the final output reminds me of flow over a cylinder. Hence why I asked about the simulation time. I understand that after a certain time the values will reach an equilibrium, I’m just curious to see if you had simulated long enough passed that point. That way, the swirls would have enough time to propagate down the channel.
Try to check this thread to see if it helps at all (Flow over circular cylinder). Again, I could be totally wrong, but where’s the harm?

Mr.RaiderDoctor, it is worth to give a try. I will extend the simulation time and see whether it gives a better visualization results. Thanks for enlightening me.