I'm a student and learning the fundamentals, mostly worked with fluent and openfoam, looking for jobs and many companies ask for Star CCM experience.

I am a senior mechanical engineering student currently working on a project that involves designing and improving the design of an aerodisc for motorcycles, I was told I would need to learn cfd to accomplish this by my professor, where should I get started (like youtube videos and tutorials) I would preferably like to learn this while learning how to use a software like ANSYS or some other tool to help speed up the learning process (I tend to learn better that way).

Hi there,

as the title says i wanna write a study work about a CFD-Simulation and later down the line possibly include a more sofisticated simulation into my Diploma for HVAC Engeneering.

My idea ist to analyse the air flow in a room with the following conditions. I want to look at draft as my focal point for now.

- central aircontidioning (2 Intakes 2 outlets)

- for now a cooling system idealy a regular airconditioning unit with forced konvection and using recyceled air from the room or a easier solution relying on free convection

Right now im wondering if this is to complex for an absolute beginner using CFD-Simulation or would it be douable, as i only got around 5 months till due date.

I hope my English isn´t too dreadful to read.

Thanks in advance!

I have to simulate slug flow in a pipe using ansys fluent as well as openFoam. Would be helpful if I can get some tutorials and literature to decide the parameters for my study!! Please do share of you have any material regarding multiphase flows especially slug flow

Hello, trying to model gassification with only 1 homogenous reaction and 1 hetrogenous reaction. I unfortunately I dont understand why this error is happening. See image below. Ive already ran a hydrodynamics simulation so its probably something to do with the species transport, I would appreciate any and all help.

https://preview.redd.it/jdc5p3aochge1.png?width=1239&format=png&auto=webp&s=cd7cb46bcac31a4c7811e4f79a63864b9c85b372

Case File: https://drive.google.com/file/d/1f-9ciOoKxprwSQbqmiIwkM2PLIul61aE/view?usp=drive_link

Hello guys, i want to install openfoam. I have windows system. I tried to install sublinux for windows but the system is lagging as a generic problem.

I want to create a new partition on my SSD to install linux as my secondary os. I am going to analyse the ship motions with the characteristics length between 0 up to 24 meters.

I have an external transportable ssd with a port supported high transfer speed. My computer also has the ss port.

What can be the best option to install to obtain better performance, on the internal SSD with partition as secondary os or on the external SSD? Thanks

Hello all,

I've been trying to perform a CFD simulation of a 3D wing. Since there is no aerodynamic data available for the airfoil profile I used, I ran two separate models, one using VSPAERO's VLM and another one using OpenFOAM potential flow using cfdof in freecad. OpenFOAM's mesh was created using the wing geometry exported by OpenVSP (as a STEP file), so essentially I should be getting similar results.

From what I found online, you get the force by integrating the normal and axial components from the pressure distribution using filters, resulting in a total lift force and total drag force. I would like to get your insight on which velocity should I use to calculate the coefficients from the forces given by the OpenFOAM results, since VLM uses 1 m/s freestream, using this velocity gives me absurdly high values for CL and CD.

I appreciate any help. If you have any further questions about my model please do not hesitate to ask.

Thank you!

https://preview.redd.it/xcq0askav8ge1.png?width=655&format=png&auto=webp&s=f1d0e0b9de0eb1ad69e55feb9d972117ced3a3fc

https://preview.redd.it/lrd9kskav8ge1.png?width=1280&format=png&auto=webp&s=0aa658fc5314ed8a289743131e57ad0769e43958

https://preview.redd.it/an7oe85wv8ge1.png?width=1282&format=png&auto=webp&s=6e41f7d72fb3daee671b8437276b8ac7347f13ca

Hello. I am very new to using expressions in Ansys Fluent. I am trying to get this zone of the mesh to rotate by 1.0472 rad/s until it reaches pi/6 radians and then stop rotating. When I include units I get the error: "name 's' is not defined"; however, when I don't include units I get the error that all arguments must have the same units. How can I fix this error, or is there a better way to achieve my goal? Thanks in advance for any help you can give me!

What are some good supervisors/labs one would suggest for working in the field of computational combustion (can be related fields as well like turbomachines flows, multiphase flows etc) especially in Europe (can suggest any other places)? If possible can someone mention their experience with the supervisor. Here 'good' means more on behavioural aspect and maybe some comments on labs that definitely needs to be avoided?

Hi guys.

Unfortunately i cannot provide any images, but i am trying to calculate heat transfer coefficient of a cooling jacket (water). I am using an older version of autodesk CFD. My boundary conditions are inlet volume flow, inlet water temperature, outlet pressure of 0 Pa and heat flow to water. My analytically calculated value of Reynolds number is about 5.5 times smaller and so is my expected heat transfer coefficient.

Has anyone ever had similar issues and can provide some suggestions?

Hi! I would like to ask something related to reactingFOAM simulation with LES. I'm working on spherical combustion and I'm doing both 3D and 2D scenario. I initially started on the 3D case and it's going well so far. I ignited the combustion by using local high temperature using setFields. The first video is the 3D case which shown the "flame propagation" through the movement of radial velocity on the right graph.

https://reddit.com/link/1idlvyg/video/8k7jnv6jk4ge1/player

Then, I copied the exact same configuration (controlDict, momentumTransport, etc) and apply it to the 2D case. However, as shown in the second video, the radial velocity is decreasing across the radius unlike the 3D case. I assume that the combustion reaction only occurs for a short time in the beginning and the combustion is not self-sustaining and hence resulting in decreasing radial velocity.

https://reddit.com/link/1idlvyg/video/43flvxpkk4ge1/player

I believe the treatment for 2D case is different than the 3D case, could anyone please give some insights or discussion regarding this problem? I highly appreciate it!

Dear CFDers and OpenFOAMers,

I want to create a room and then place human figures and tables inside it.

I have already done this in Salome by defining groups (inlets, outlets, humans—each human as a separate entity—tables, etc.). I meshed the entire geometry and refined the mesh near the boundaries.

Once I move to OpenFOAM, ideasUnvToFoam works normally, checkMesh runs without errors, but the internal elements are assigned to faceZones instead of being recognized as internal boundaries.

I have read several threads on this issue and tried multiple approaches:

-createBaffles: This generates faces for my internal elements, meaning my human models, for example, end up with human_master and human_slave surfaces. However, this is not what I need—I need the internal volumes to be defined as boundaries so I can use them for thermal purposes later.

-Manually adding faceZones to the boundary: I attempted to find the faceZones and add them manually to the boundary, but checkMesh then reported "multiply connected (shared edge)" errors for all internal elements.

Using topoSetDict: I tried creating sets for the internal elements with topoSetDict, then defining them in createPatchDict, but createPatch only works if the boundary already exists.

Here is an image of the geometry (for now, I have only included four humans and two tables as a test).

createBaffles seemed to work, and the simulation ran for a while, but I kept getting spikes in epsilon and k. Then I realized that createBaffles only generates surface faces rather than true 3D elements.

I can provide more details if needed. Thanks in advance for your help!

https://preview.redd.it/bbmdryq8h4ge1.png?width=2187&format=png&auto=webp&s=dee9cdd42cc1329d9f7d8736cf042dc87b4e2c75

Hello guys!

Does anyone here have experience writing code and/or working with the streamline method? I have never heard about this method in my undergrad studies, only got to know it very recently. Got to know the equations through the Schobeiri book, but I have no idea how to discretize them. I know there are some cool tools on github, like Turbo Design 3... but I didnt found no documentation for it.

Let me explain what I need: I want to design a blade cascade with a very specific blade loading/pressure coefficient distribution. I know that this can be done with the streamline method. Though Im aware that a pannel method would be better for this (in fact, Im trying to get a MISES MIT license for this), but Im still curious about what the streamline method could do for me.

So I'm simulating water flow around a fiber I try to simplify by making a bigger cylinder as the water and a smaller cylinder as the fiber, the problem is the fiber surfaces which are enclosed by the water cylinder (the big cylinder) cannot be chosen for the heat flux condition what to do?

https://preview.redd.it/lj0rwjn3vzfe1.png?width=523&format=png&auto=webp&s=ab84fbb93988fc86d8c80c12c24e50227aa2749d

As shown in this screenshot of the k-e turbulence model in Ansys Fluent, there are a lot of additional options and values that can be changed. Is there any good literature that discusses turbulence models for CFD and when to use different model variations?

Hi all,

I'm working on a 3D transient combustion problem with Ansys Fluent (2024 R1). I'm using Reduced-order models (mostly Steady-Diffusion Flamelets and Flamelet-Generated Manifolds), and I want to compute the total heat release rate in my model.

I'm running into the following issue: at the start of my simulation, the HRR is highly negative and remains constant during 0.2-0.3s before increasing.
This issue is not related to mesh or timestep size and appears on all reduced-order models (even without flamelets).

Has anyone encountered similar behaviors?

Hi everyone. I am hoping to find some help here.

I am a master student and soon I have to use Flow3D-Weld from my uni to do some laser keyhole simulation. I am wondering if anyone uses Flow3D-Weld and could share me where to find learning resources and dedicated community to the app Flow3D-Weld.

I am awared that it is closed-source and so far there are only a few Webinars from them on Youtube.

Some keywords relating to what I study: melt pool dynamics, keyhole simulation, hot cracking, lattice Boltzmann.

Thank you in advance and have a great day!

Hi all,
First of all, I apologise because I don't think this is the right sub to ask about this, but since r/AskEngineers need karma to ask questions, so I reckon I should give this sub a try.

Just for context, my project will be focusing on wind blade designs, more specifically towards the optimization of the design for wind harness and manufacturable of blade that fit for purpose for wind source energy, for small scale applications.

What is the best software that I should use to design multiples different design of wind turbine's blade, and can run simulation to simulate:

• The CFD of the blade design and the power output
• FEA of the blade
• Can simulate the power output of each design that can be harnessed from wind

I had one design that my professor asked me to design, which is like this (https://imgur.com/a/HlVMPRW). My professor said that I can use any software that I'd prefer, but I just want to get a clear thoughts on which software is the best to make such design as in the sketches that I have.

Thank you very much.

I know this question has been asked a million times but I just wanted to ask again in case there have been any new developments. I do external aerodynamics of complex geometries that need me to resolve the boundary layer and I have found it impossible to generate a satisfactory mesh with inflation layers.

I have tried snappyhexmesh which invariably collapses the inflation layers with even slightly complex curves. I have tried the approach of adding one layer at a time after the snapping step and that suffers the same fate. I have also tried modifying the meshqualitydict to make the mesh quality parameters less stringent but that leads to horrible quality meshes with negative volume cells.

I have also tried cfmesh. It is able to generate an inflation layer but the mesh quality is really bad. Also, the prism cells it generates are very thin compared to the outer mesh.

I have played around with the SHM and cfmesh parameters for a while now and I am just not able to make a good quality mesh with inflation layers.

So, the following are my questions:

1. Have there been any new developments or are there any alternate tools I could try that could help me generate a good quality mesh (preferably hex dominant) with inflation layers?

2. For those who have had success using SHM and/or cfmesh for external aerodynamics, could you tell me the parameters you used? I get that these could be case dependent, but it will help me get an idea.

I’m trying to make a fluid sim to test different resin mixing devices. The issue is when I try to mesh the propeller, and the “cup” together, I a topology error with the possible cause being “parts cup and propeller are not disjoint.” I’ve not seen this error in any other forums, or STARCCM’s documentation. If anyone has any ideas as to why it’s happening, and how to get it to operate properly, that would be great.

Hey guys, I'm currently in my 2nd year of physics undergrad.
I came across this field and it looks very interesting, and got me wondering - how can I break into this field? Are there any advantages to studying physics? Or will I have to get a CFD Master's / PhD anyway and it doesn't really matter what I did for my Bachelor's?

Also, what is the salary like in the field?

Thank you for your responses!

Sup dudes and dudettes.

Wondering if anyone here has experience with SimFlow and could list some reasons to get into it, and what benefits it can provide. I can't seem to find any solid information on what it does better or improves over standard OpenFOAM. From their website, it just seems like they make it more user-friendly for setting up a simulation. And while OpenFoam can be painful, its not a major problem since i work simple geometry’s and problems.

I've only used OpenFOAM unmodified since that's what my university focuses on to an almost religious effect. If there’s a better option out there, please let me know. Would be cool if it can make my master thesis a less pain in any form.

Dont wanna waste more time on tangents that leads no where. So asking you guys before i try anything.

Hi everyone,

I’m exploring how engineers like you approach CFD workflows, and I’d love to hear about your experiences. What does a typical day look like for you when working with CFD tools?

• Are there any parts of the process that feel repetitive or time-consuming?
• What kinds of tools or methods do you rely on to streamline your work?
• How do you typically go about troubleshooting or making decisions based on your results?

I’m not looking to sell anything—I’m just trying to learn and understand the realities of CFD work better. If you’re open to sharing, feel free to reply here or message me directly. I’d also be happy to set up a short call if you prefer a more in-depth chat.

Thanks for helping me learn from your experience!

how should i mesh it? should i mesh it with boundary layer at each of it surface or just a uniform element of meshing. Or something mosaic type of meshing (polyhexcore)??

I'm a student currently doing courses and internships on CFD practically, I am mostly familiar with external car aero and battery thermal CFD analysis as a student and did few projects on the same as an intern using OpenFoam and fluent mainly.now looking for opportunities as CFD application engineer.

I'm thinking of broadening my scope and searching for industrial CFD problems that I can get my hands into and gain experience. I'm curious on hvac analysis in civil engineering field,

Any experienced engineers, please share your thoughts?