[KVRC] Khamsin Virtual Racecar Challenge 2016

[etsmc]

well had a pm from Chris saying my diffuser idea would not be compliant with the rules so not sure whether to try and make it rules compliant or just to ditch it.

[LVDH]

I do not think it is possible to make it complainant. But you could still experiment with it. Maybe we will learn something interesting. Possibly it could be allowed within next year's rules.

As we did not receive any emails from KVRC, I guess the submission deadline has really been pushed back?
I would not mind as all CFD I was doing for KVRC lately was to figure out what made the simulations so strange.

[RicME85]

What makes it illegal?
I had the Jordan diffuser step on a car last season.

[LVDH]

As far as I understand this:
K3.3 ­ floor
...
● When any bodywork specified in this rule is intersected with any plane normal to
the X or Y axes, there must be no gaps in any of the sections formed
(considering only one side of the car). Surfaces inside the diffuser which are
vertical will be considered to be visible from below. The engine exhaust outlet
surfaces are ignored for this requirement. A small tolerance will be allowed in the
area surrounding the wheel well.

[etsmc]

Lvdh is correct. I have changed the design a bit so that it does not turn back in on itself and have a simulation going so will see what it shows.
Because i dont get the results from occfd is there any way i can use the forces.dat file? Will need to be simple instructions if you do know.

[RicME85]

just right click it and open with wordpad (wordpad is better than notepad as it separates into lines, notepad just gives a massive block of text)

[machin]

Once he has opened up the word pad file which numbers should he be looking for to indicate any changes...?

[RicME85]

should be the last group in between double brackets, will look something like this:

((2.322994e+00 1.498414e+03 -5.258119e+03) (-9.474148e-03 8.005821e+01 1.023900e+01) (0.000000e+00 0.000000e+00 0.000000e+00)) ((-9.717254e+03 -2.131379e+00 -4.427578e+00) (-3.618850e+01 -9.022764e-04 1.055536e-02) (0.000000e+00 0.000000e+00 0.000000e+00))

Then you go to the CoP Spreadsheet Julien did before OCCFD, when we were using the Khamsin plugin, and compy and paste the data into it.
If you havent got it, it was shared a few pages ago IIRC or there is this link from my Google Drive. Save it so you can edit it. I copied and pasted the cells so I could compare data side by side.
https://drive.google.com/file/d/0B2lgcR ... sp=sharing

[andylaurence]

Did you ever sort out your scanned model Andy?

Not really. This is as good as I have. that might be good enough to start work on a new floor once wings and wheels are added. I've just printed a pair of winglets to go on the front wing end plates for Saturday.. Balance is far too rearward.

[Alonso Fan]

If submission closes tonight, I'm afraid I'll have to skip this race. I have a thermodynamics exam tomorrow and no time for my car at the moment. I should hopefully restart development in the next week or so

[cdsavage]

Round 2 will definitely be delayed, it's just a question of how long - I would expect something between 1 and 2 weeks, but I need to hear back from Julien before we can set a firm date.

[Alonso Fan]

That's better for me, that way I can focus on my car after exams

[graham.reeds]

Are there any intuitive packages out there?

I tried SketchUp, but the free version doesn't give you the ability to perform boolean operations. So I am trying FreeCAD.

I am trying to do something that is conceptually very simple. 3 slightly overlapping cylinders, and a couple of cubes. Two of the cylinders stood up right but slightly off center, so if viewed from above look like a Venn diagram. These I want to perform an Intersection so I am left with a cat's eye cylinder. Then another cylinder this one being on it's side to use it to punch a circle through the model. You then use the cubes to cut away one half and then the second one to remove the bottom so you are left with what looks like an upside down prow of a ship.

Easy. No. I can create a cylinder but it is on it's side. So I click transform. I get free hand draggy green arrows but no apparent way of saying just rotate by 90 degrees. Same with move - freehand is not good. I want to move it by a specific amount and I need to be precise so when I do the boolean operations I am not left with floating bits because they were off by a pixel when I dragged it.

Every time I commit to getting something done I leave with nothing to show but a massive sense of frustration.

Just having a rant.

[variante]

While it's true that no boolean operation can be done with the free version of SketchUp (unless someone has made a plugin for that...and it is likely), the boolean can be easily reproduced "manually".

The shape you want to create can be made in SketchUp, and can be produced in similar amount of time to other CAD softwares, such as SolidWorks.

Not sure what you mean with the last part, but moving things by a specific amount IS possible.

The actual problem of SketchUp is the lack of precision, which definitely reveals the non professional nature of the sofware.
Such precision, however, is enough to design a great car for our championship.

If you want to know how to make the mentioned operations, just ask

[RicME85]

Get on Sketchucation, there is an abundance of plugins on there.