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BlitzWing97
10-05-2017, 07:03 AM
Every model i produce for the side pods seem to have a form of flow reversal at the very start; a high pressure bubble if you will. I've been told a fan will sort this problem out however i do not know how to model a moving fan inside of the pod. This is what i require help with.
I cannot find any tutorials or videos that meet my needs so any advice is good advice really


Regards.

Claude Rouelle
10-05-2017, 03:08 PM
Not worth to introduce your self?

This is not a supermarket!

Bit of politeness and courtesy would not hurt anybody......

Owen Thomas
10-05-2017, 05:47 PM
You will want to simulate the effects of the fan by introducing a couple new boundary conditions: one right before the rad, and one right after the fan. Your fan spec sheet will have data about pressure drop across it, for starters. Make some assumptions to fill in the other variables and iterate. Lastly, get some pitot tubes to back up your sims (bonus if you do that on a previous vehicle right now for a solid starting point).

BlitzWing97
10-05-2017, 06:41 PM
Claude Rouelle
i understood this was a forum not a dating site~
And as my first post i'm pretty sure any snide, unrelated comments aren't really worth posting...Just a thought

BlitzWing97
10-05-2017, 06:42 PM
Owen Thomas
Thank you! First bit of helpful information on the interent haha. Theres zero sources on how to do this unless it is an actual CAD of a fan.

Mikey Antonakakis
10-06-2017, 02:04 AM
Claude Rouelle
i understood this was a forum not a dating site~
And as my first post i'm pretty sure any snide, unrelated comments aren't really worth posting...Just a thought
Better hope Claude doesn't end up as your design judge!
I am going to hazard a guess and say you're relatively new to Formula - it's a good idea to give some introduction of yourself, and some context for your problem. This is a warm community, but everyone involved is super busy. If you can demonstrate your level of understanding, show that you've done your "homework" up to that level of understanding, and ask pointed questions, you'll get an endless stream of knowledge and aid.
In this case, you started two identical threads on a relatively low-activity forum within minutes of each other. You didn't provide any of the previously mentioned background, just listed what you "required."
Believe it or not, engineering is a relatively fuzzy discipline in the real world... Tact goes a long way.

Anyway, to answer your question, have you read the users manual for your CFD software? Have you taken a class or searched for a book on CFD modeling? There's some advice for you, if you haven't done that yet.
And a more widely-applicable piece of advice: engineering is not about being able to look up instructions on how to do something, and then following them. I think that relates more to arts and crafts. Engineering is about applying basic principles to solve complex problems.

So, why do you need to make a CFD model of a moving fan inside a side pod? What are you trying to accomplish at a high level? How do cooling systems work?

BlitzWing
10-08-2017, 02:17 PM
Yes I have done my research. And there isn't any reading material I have found which is informative enough to tell me how to achieve what I want. Arts and crafts is more expression. You cant follow a routine. Engineering there is structure there is a way about things. I think you've gotten the two mixed up.

I wish to model a fan in the side pod so I can accurately evaluate the pressure distribution and velocity gradients internally.

BillCobb
10-08-2017, 05:38 PM
If the startup is your concern, run the play to a steady state and use the final state conditions as the new set of initial conditions for another round to see if there is a stability problem or an incorrect or unusual or missing state value.

This is called "bootstrapping", sort of a manual iteration to see if there are conditional or computational mismatches. May take several tries.