Uni Project

[Danny McGee]

Hiya folks,

Am bored with writing my interim report at the moment so thought i would share with you my lastest creation in solidworks. Its for my final year project (one of anyway) were currently desining a car that will go as far as possible on 1 gallon of fuel. The current record is around 12,000 miles :O lol

As we only have 8 months to design, make and compete i dont think were heading for that kinda distance but something aroung 5,000 would be nice.

For the people in the know, i hate using solidworks as a surface modeller, its pants, it wont follow guide curves, mirroring splines creates all kinds of projects with regards to the "zebra stripes" and dont ever get my started on the rear fairing, one slight change and the whole thing go "mer" basiucally.

Anywho. Back to it i guess

Moi

[ben]

looks pretty cool danny. Is tom cockerill making or designing a One way diff or something???

lil ben

[Danny McGee]

Erm yer i think so, last time i spoke to him about it he was making a one-way. That should be fun for him as its all gotta be done by hand machining, i.e no CNC stuff lol. Good luck with that Tom

[tc2k]

Really wanna do autosport engineerign at uni but seems a bit fo a risky business to get into, not exactly brimming with oppurtunities I dont think.
looks awesome though mate

[ashleyb4]

cool who will drive it??? and where will you go thats like from john o groats to london 4times with a bit more left over.

A

[josh_smaxx]

Looks great, always have the greatest respect for anyone who can use solidworks

I think i am doing the motor sport engineering degree, my idea is follow your dream.

[Fabs]

Hey Danny nice one. I've never used the Surface modelling feature of solidworks, but I'm quite good with solidworks otherwise. You tell Tom if he wants a one way he should ask me, after all I'm the one working with CNC lathes and machining centres all day...

[Danny McGee]

We have 3 drivers at the moment. We took all there dimensions today so i can make the bodywork at close as possible to them. There only little tho i think the tallest is about 5'6 and they have to weigh less than 55kg. The car itself shoulg be about 30kg with the engine, steering, braking etc. Were going to rockingham on the 2 and 3rd of july i think it is. Basically they give you a set amount of fuel, weigh the car, let you run for an hour and then reweigh the car. Then using black magic they calculate the fuel used. I suppose it an equivilant MPG as we dont actually go that far (think the driver may get a bit bored at an average speed of 15mph)

It is an awesome course, but as this is a new project for this year its a LOT of work, especially considering im having to learn how to use a program called FloWorks which is basically a virtual wind tunnel. Crazy stuff

Stroll on may, i only have a masters to do after that

[Danny McGee]

and whats the chance you have a 5 axis cnc machine that my uni could use for a couple of hours? It would basically to machine all the bits for the engine and the steering.

Whats your company? I could give them a call and see if they are interested in joining our ever increasing sponsors list.

And if the price is right we will even let the company use the car to show off there maching skills

[Fabs]

Originally Posted by Danny McGee

and whats the chance you have a 5 axis cnc machine that my uni could use for a couple of hours? It would basically to machine all the bits for the engine and the steering.

Whats your company? I could give them a call and see if they are interested in joining our ever increasing sponsors list.

And if the price is right we will even let the company use the car to show off there maching skills

3 axis only but if you show me the parts i'll tell you if we can make them. I don't think they'll be interested in sponsorship, it's only a small company, although the boss is a fan of motorsports so who knows...

[glypo]

If you think SolidWorks is rubbish for surface modelling....... you haven't used ProEngineer. Honestly there is nothing worse then ProE for surfaces IMO. Just a couple of days ago I was modelling the most basic of wing planforms and I was getting crazy results. In fact I'll show the result:



Using same aerofoil section, only at a smaller chord and thickness, it decided the best surface plot involves this crazy crease in the wing. After plotting 20 sections and still no real cure, I ended up photoshoping the images for the technical report and drawing the wing itself for the CFD analysis again using gambit! If only everywhere had Catia...

Anyway this brings me onto the whole reason I made the post, aerodynamics. What kind of speed are you looking at getting? The whole car seems like it will have a lot of flow under the body. I just wondered what the lift coeffcient would be, potentially quite high... which might not be a bad thing for a a car of this design? The Cd0 should be low for sure, and providing any lift generated is perpendicular induced drag should be low to.

Good luck with Floworks, it's very easy to use. Just be very careful setting up the atmospheric conditions. I found every time I loaded the file, even a full case study, it would not remember the atmosphere so had to type it in a lot. Fluent is the same as well for some reason. Very interesting project indeed, hope you keep this thread updated.

[Danny McGee]

The max speed will be 20mph. The idea of the flow under the car is to avoid a collision between the boundary layers, nothing been measured as of yet. At the moment the angle underneath hasnt yet been modified (gonna do that with the use of floworks) Cd is about 0.075 at the moment. with a frontal area of 0.254m2. I think thats a wetted area of 0.01772 but dont hold me to that one.

With regards to fluent/gambit. wwe've only been show how to do 2d (obvious infinate) shapes, which is rather annoying due to the fact that the fairing arent infinate. Still trying to get my lecturer to pull his finger out and show me 3d gambit.

Floworks seems pretty easy to understand if im honest.

I just wish we had catia, it would make our life so much easier, even unigraphics would help. Im currently doing a report on the theroy behind solid and surface modelling and i can assure you its not very interested. Nurbs this and B-Rep that ZZZZZZZZZZZZzzzzzzzzzzzzzzzzzzzz

[Alfonzo]

I might have the wrong end of the stick here, but I *think* me and my brother met you at the Petit 2007 event last weekend - had a quick chat on the Sunday? Anyway, we own a small CNC workshop and are pretty damn good at prototype parts, small batches etc. so don't hesitate to get in touch if any good to you.

Good luck

Al

[Danny McGee]

Yer that was most probably me last weekend. Chatting about how busy i akm at uni etc. I may well be sending you a PM on monday once ive had a chat with my class mates about it all sounds good to me tho.

I'll get back to you on it.

Danny

Originally Posted by Alfonzo

I might have the wrong end of the stick here, but I *think* me and my brother met you at the Petit 2007 event last weekend - had a quick chat on the Sunday? Anyway, we own a small CNC workshop and are pretty damn good at prototype parts, small batches etc. so don't hesitate to get in touch if any good to you.

Good luck

Al

[rich_cree]

I think the bluff leading edge of your design and the lack of curvature continous surfacing is going to hurt performance some.....but not as much as the lack of wheels will

[rich_cree]

Originally Posted by glypo

If you think SolidWorks is rubbish for surface modelling....... you haven't used ProEngineer. Honestly there is nothing worse then ProE for surfaces IMO. Just a couple of days ago I was modelling the most basic of wing planforms and I was getting crazy results. In fact I'll show the result:



Using same aerofoil section, only at a smaller chord and thickness, it decided the best surface plot involves this crazy crease in the wing. After plotting 20 sections and still no real cure, I ended up photoshoping the images for the technical report and drawing the wing itself for the CFD analysis again using gambit! If only everywhere had Catia...

Anyway this brings me onto the whole reason I made the post, aerodynamics. What kind of speed are you looking at getting? The whole car seems like it will have a lot of flow under the body. I just wondered what the lift coeffcient would be, potentially quite high... which might not be a bad thing for a a car of this design? The Cd0 should be low for sure, and providing any lift generated is perpendicular induced drag should be low to.

Good luck with Floworks, it's very easy to use. Just be very careful setting up the atmospheric conditions. I found every time I loaded the file, even a full case study, it would not remember the atmosphere so had to type it in a lot. Fluent is the same as well for some reason. Very interesting project indeed, hope you keep this thread updated.

The crease is due to the program lining up knot points in a spline, you need to change the sheets alignment to arclength or similar.