[KVRC] Khamsin Virtual Racecar Challenge 2016

[LVDH]

Not sure what angle you mean.
But if you dig out the old pictures of the winning cars, it is still the JJR front wing I am using.

[CAEdevice]

I mean the upper element of the front wing. You are right, JJR used a similar geometry last year. How does such a vertical profile help producing df? It works like a big Gurnay flap?

I choosed an opposite design, at the moment it looks not a very good choice.

[LVDH]

I only stole the design. I am not sure how it "helps".

To me the wing more or less decelerates the airflow in front of it which cases a nice high pressure on the front element. It is so extreme that the first element works more like a splitter.
But as the airflow somehow does stays attached at the rear it does work like a wing and the lower parts see very low pressure which is exactly what you would want. Getting the wing to work properly is not super simple though. Slightly changing dimensions like overall size but also width can dramatically change front downforce.

I use it as I have not come up with anything better and the numbers are great. But I like the new design from JJR more. Maybe I will steal that too.

[julien.decharentenay]

@CAEdevice Most of the time I hear a comment from one of my software provider it goes by "we will fix this in the next version". I have been through this process enough to know that, generally, the next version has its own set of problem - and I would rather not promise that everything will get fixed...

On this, the shiny new patch that I promised a while back is available at http://www.khamsinvirtualracecarchallen ... .1-010.zip It has an implementation of the porosity that "should" be working in principle - there is one aspect to sort out is the extraction of the flow rate through the radiators (during the simulation and at reporting time).

There are two keys aspects with this patch:
- blueCFD-Core-2.3 port of openfoam is supported out of the box http://joomla.bluecape.com.pt/index.php ... lect&id=45 - I have great hopes that this will solve the parallel solver issues that have been a plague for you guys. The cfdsupport version of openfoam is also supported - so if it worked for you there is no need to go to blueCFD;
- I fixed an issue with the calculation of the normals for the intake/exhausts (error reported by MantiumRAY). The issue occurs when faces within the same intake/exhausts are facing in opposite directions.

There are a few other issues (output scale on AWS for ex) that I have fixed (and hopefully I haven't added too many new bugs).

28th April is the submission date.

[machin]

I have prepared a similar package.......

Cool. These should make it easier for people to enter, although I can also understand why an entrant would want to design their own entire car, even if it would be technically inferior to a "customer" car. I must say though, if someone wins the Introductory class with my bodykit it will be entirely because they have designed a good set of wings and diffuser....

[JJR]

Thanks LVDH for compliment.
Verry good efficienty of your car LVHD. Maybe you can sacrifice of your good cooling for even more efficienty.
It will be hard to get to Variante huge downforce levels. Without cooling broblems ( and I think he can easly fix it) he is on the top.
TF was last year promissing and this round get podium with good efficienty as usual.
I like Matteo car too. If you can find front downforce you can be on podium too.

And to my car:
2015 3-element front wing was producing huge front downforce but it was shifting to much downforce to the front because centre of downforce of that wing was much forward ... and it was also effecting flow to rear wing. (with new solution it is not problem)
It was verry hard for 2016 to make front wing work but it payed off. Alone it make much less downforce than last years but for hole package it is better. It only work with curent front susspension/cooling/front floor package ....
I still use same diffuser and rear wing as in 2015 car.
I´m usually quiet in this talk because of my bad english and often forget my password for login to the forum

[CAEdevice]

Your english is not worse than mine.

I am using the same rear diffuser of 2015, and the rear wing is similar too. At the moment I have only worked on cooling devices and front wing.

[Alonso Fan]

ok, so I ran occfd from around 10pm last night, multicore, and I came back to it at 10am in the morning and it had gotten to 'simulation 1, resolving mesh with snappyhexmesh'. I thought it was strange because last time I tried the simulation on single core it took 9 hours, not 12. I figured it was stuck but no error was posted. so I ran a singlecore analysis at around 10:30am this morning and it would have finished within 8 hours, had someone else not logged me out. I checked the log. it was almost done, and the .foam file when viewed in paraview definitely had decent results, the html was missing due to the simulation not finishing completely but it was almost there.

so, single core, 8 hours
multicore, 12+ hours

this isn't normal. I was trying with openfoam 2.3.
i'll try with bluecore tonight, and post back tomorrow

[CAEdevice]

Hi, with OCCFD 1.0.10 I noticed that preprocessing and meshing require more time, but the test simulation is still running, so I don't have a complete feedback.

[Alonso Fan]

it seems I've done something wrong. I think I may have installed bluecore in the wrong place?

I used the default install path

[Ft5fTL]

http://i63.tinypic.com/10glgm0.png

it seems I've done something wrong. I think I may have installed bluecore in the wrong place?

I used the default install path

I have that error too.

[Alonso Fan]

http://i63.tinypic.com/10glgm0.png

it seems I've done something wrong. I think I may have installed bluecore in the wrong place?

I used the default install path

I have that error too.

did you uninstall the openfoam 2.3 from cfd support?

[Ft5fTL]

I did remove the files from my harddrive but didnt uninstal them. After that i installed the bluecfd. Got the same error both on them on the simulation phase 1.

[Alonso Fan]

I did remove the files from my harddrive but didnt uninstal them. After that i installed the bluecfd. Got the same error both on them on the simulation phase 1.

Right well I also uninstalled openfoam then installed bluecore. I got that error. I reinstalled openfoam up to the part where it asks to install paraview 5.0. Occfd still seems to be using bluecore but it's working now. Currently running a multicore simulation.

Try reinstalling openfoam from cfd support. But keep bluecore installed because occfd will use it

[Ft5fTL]

It seems its working with your solution. The only different thing is mine uses the cfd support version.