[Ahim_Edogan]

Hello.

I want to know what is your prediction on estimation on how much time it will take me to successfully finished the following simulation (I just start with openFOAM – just start the wiki tutorial)?

p.s. I do not need the perfect examination, just rough prediction on how different “flow distribution” impacting on flow distribution in fixed bed reactor. I want to know if is worth my time (I am think to add simulation in my master degree).

The simulation: What is the simulation of flow through the fixed bed reactor and how different flow distribution impacting on flow uniformity through the vessel?



link to picture: https://drive.google.com/file/d/1vmK...ew?usp=sharing



First I want to simulate just the flow through the flow distributior and than the flow in the vessel.

In my master thesis we will examine the different type of flow distributor (the size and position of holes) on the flow through fixed bed reactor (vessel).

So What is your estimation, how long I will need to working on my simulation (I can do 3 hour per day – everyday). If you have any suggestion please share. thanks ahead.

[JulioPieri]

Hi Miha, welcome.

It's impossible to estimate how long will it take. We don't know you pc configuration, your refinement level, 2D vs 3D, your domains size, which models, characteristic velocity, transient vs steady... Even with all that, only people that have worked with the same solvers/models could estimate, as there is no "rule of thumb calculation" to estimate that.

A good start would be using twoPhaseEulerFoam (which I happend to work a lot with recently).

Are you familiar with CFD? It's very very important to create hypothesis to simplify your study - your domain, for instant, can take great advantage of axissymmetry.

So let's imagine you have a regular 3-ishGHz pc, with 4 cores, and you are using the twoPhaseEulerFoam solver. If your domain is a cylinder with 100mm x 300mm aprox (from image), and you have a excessively over refined mesh with 2mm, you will have roughly 300k elements in a 3D simulation. You could split it into 2 cores, and run for 20s on a transient case I'd estimate around 5+ days based on my experience with twoPhaseEulerFoam. If you simplify to 2D, then you could have results with only one core, run several different cases simultaneously and get results within 4-8h.

Again, this is a grotesque approximation. I'm not an expert and more info on your case will not be sufficient. The best thing you can do is study openfoam to create your case and start the simulation. In the first timesteps you will see how long they take and then you can estimate the time to completion. If you are familiar with CFD, the learning curve can be quite steep and in some days/weeks you will be comfortable to create you case.

Remember, ALWAYS make simplified cases before jumping into the final one

[Ahim_Edogan]

thank you for responding.

I was asking more about the time it will take me to learn and implement enough knowledge in simulation that I can use it like rough results. But every advice is good to hear. thanks