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Hello, this problem was something that I came up with. You can find some example problems online or from textbooks. A favorite book of mine is "Computational Fluid Dynamics, A Practical Approach" by Tu et. al.

@@cfdkareem Thank you

It's in the works! Should be out in a week or two!

@@cfdkareem thank you for your responses and your videos they have been super useful

Hello, for 2D planer geometries the default "depth" is 1 m, which can be set in the reference values. It will not change the simulation, but you can change this value to something smaller in the "reference values" tab. Again, the depth is arbitrary for 2D models as long as you calculate and apply the volumetric heating correctly to achieve the correct wattage.

@@cfdkareemThank you for the response, I hadn’t realized that 1 m was the default. I was able to figure out my volume using the volume integral tool and then do the math to apply the right wattage. Thanks again for making this video

If you use the enclosure tool, as shown in the video, there is no need. The tool will automatically apply Boolean operations and remove the volume of the solids from the enclosure.

Send me an email to kareemcfd@gmail.com explaining your problem and I'll see if I can help!

Glad it was helpful! This is a great example for the use of boundary profiles.

Glad you found it helpful!

Hello, the easiest way is to create an enclosure around the whole object and then use the splitting tool to split the enclosure at ground level.

Hello, Workbench can be a little funky with exporting data to CFD-Post. In Fluent, you can try manually exporting the results by going to File>Export to CFD-Post and selecting the variables you want to export on the right side. You can then open a new CFD-Post window and load the results.

@cfdkareem thanks, will try that. I had manually noted it. Your videos are really a great help for us. ♥️

oh I found it, shared topology :|

Hello, I have a video coming out soon on deposition of droplets on a substrate which may help you. For binder jetting you can do one of two things. First, you can try depositing droplets onto a "porous media" which will use a mathematical approximation for the wetting of the ink into the powder. Second, much more complex, you can create a STL file of a small region of powder and deposit the droplet on top. This will require a very high fidelity 3D mesh and will be a complex model. What question are you trying to answer with your model? This will help me provide a better answer your question. Thanks!

Hello, I do not provide live 1 on 1 consultation, but you can email (address in channel page) specific questions and I can answer them there. Thanks!

Hello, this case was created solely for tutorial purposes and does not have any corresponding experimental data. Some estimations about the validity of the results can be gathered by solving analytical equations for the 1D heat transfer through the heated body.

In the momentum equation gravity is added as a body force multiplied by the density. If you have constant density then this force is applied equally everywhere and therefore does not impact the flow. In other words, for forced convection in a pipe of constant density you will see no effect from gravity and it can therefore be neglected in the calculation.

@@cfdkareem Thanks for you respond. If I would like to have the gravity effect present even though my density is constant. Is it possible?

@abdullaal-tarmoom3437 yes, under general options you can check density and set the direction and magnitude. For earth gravity it will be -9.81 m/s^2 in the Y direction.

@@cfdkareem this is what i did for your case, I clicked on the gravity option and choose it to be -9.81 in the Y direction. The results stayed the same. So how can I make the gravity effect present in this case? much appreciated

@abdullaal-tarmoom3437 as stated before, you will see no effect from gravity unless you have variable density for the fluid material.

Hello Moustafa, you do not need to change this option in Space Claim. The final definition for the body will be done in Fluent and you can change between solid and fluid. In meshing you can also add a named selection to the body and give it a name such as "domain_fluid". This will tell Fluent that this is a fluid domain and will assign it correctly when the mesh is loaded. Again, not necessary since we can switch it in Fluent, but nice for workflow efficiency.

@@cfdkareem Thank you for your quick responce. I am waiting for your upcoming videos, you are doing a great job. 👍

Hello, unfortunately I cannot provide a version of Ansys other than the student license. What issues are you having with the student license that makes it insufficient for your model?

Hey Josue, 3D VOF models are very computationally intensive so if you can reduce your model to a 2D axis symmetric or 2D planer it will be much simpler. I have a video coming out soon on the deposition and solidification of a metal droplet on a solid substrate. It may help give you some direction for your model!

Definitely! However, you will still have to provide a wall thickness and material for the calculation. Simple thermal contact resistance, shown in the video, models the layer as zero thickness which only allows heat conduction normal to the surface. Shell conduction will allow heat transfer both normal and planer to the wall. Shell conduction will also account for the additional thermal mass which can be useful if you have an interface layer of significant thickness.

@@cfdkareem thank you sir😊

Yes! If you check out the short on my channel it shows you where to download it and some of the limitations of the student license. Let me know if you have any issues!

@@cfdkareem got it. Can you do a tutorial of a heat sink with a cooling fan in front of it?

I have a tutorial on my channel for forced convection through a heat sink which will give you the basics for this problem. Are you trying to model the fan explicitly?

@@cfdkareemmodel fan explicitly

@kaleb101 ok great! I'll add it to my list for future videos.

All profiles must be in SI units. Fluent always operates under the hood in SI. When you change to English in the GUI it's doing a "visual conversation" well still using SI under the hood.

Deserves way more views forgot to add!

Glad you liked it!

Hello, are you trying to change the flow from air to water? Or trying to do a multiphase simulation with air and water?

Boiling is a fairly complex simulation which will require multiphase and the boiling/condensation model. Is this what you are trying?

Hello, going from voltage to pressure requires an initial simulation that models the piezo movement. I obtained this profile from such a simulation. To model this you will have to model the whole ink chamber. You can do this with a single phase simulation and have a pressure=0 condition at the outlet. You will then input the voltage profile to drive the motion of the piezo and export the pressure generated right above the nozzle. I will add such a model to my future video list!

Glad it helped!

Glad it was helpful!

There are numerous equations for estimating the turbulent velocity profile. The most common for industrial flows is known as the Prandtl one seventh power law which takes the form: u/Umax=(y/R)^1/7. You can plug in Umax and R to solve for u over the range of y.

Our teacher said u can use k-epsilon for turbulence but with that method you can only get the first vortex others only appears for the initial iterations then dissappear.

also, with very fine mesh (i have uniform 150k grids) DES methods takes almost 2k iterations to hit 10^-3 criteria and oscillations never stops as i see.

Hello, the pressure profile is in the video description!

I used that pressure profile, I wanted to know how was that generated? Do you have any reference literature so that I can modify that pressure profile according to my operating conditions. Thank you!

@AdityaChivate this pressure profile is just an arbitrary waveform for the purpose of the tutorial unfortunately. If you look through some literature on inkjet waveform generation you may be able to copy a representative one from the literature.

@@cfdkareem Thanks for your reply. I'll check around to see if there's any existing literature that talks about this.

Hello Joaquin, near the bottom of the NASA page there are two links to the Cf and Cp data. Clicking the links will open a new tab with the data displayed in text format. You can then copy the data and paste it into excel or a text document.