Project: Home made velomobile design with crank or mid motor

[perbear]

I think it is fair result. Remember you get a lot of drag exposing the front wheels, and if your vehicle profile results in lift (or downforce) it will result in extra drag.

I used the OpenFOAM based Caedium (http://www.symscape.com/node/1082) and it gave 11 N in drag at 10 m/s for my velomobile construction: I ran only half body and steady state so that simulation show some fluctuations:

 

[tahustvedt]

I guess it's ok. I'm getting 102 N downforce in the CFD though, which is just wasted energy. I'm going to try some more variations to see if I can improve things further. It's easy to draw a super efficient shape, but it's difficult to draw one that is really easy to build. I don't want to mold the body from composites. The wheel and suspension fairings will be carbon fiber.

I tried the Caedium trial, but when I tried to follow the tutotrial with my own model but it was missing a parameter under the fluid settings that I needed to continue, so I gave up. The CO2 car worked fine.

 

[tahustvedt]

I guess I should just go with it. It looks cool, at least.

 

[tahustvedt]

My latest simulation with a different rear wheel fairing resulted in 20,47 N at 10 m/s.

 

[tahustvedt]

20° relative wind. It (probably) won't tip over. The forces are at Mach 0,2, so to get the forces at 40 km/h must be multiplied with 0,02697.

 

[tahustvedt]

 

[tahustvedt]

 

[tahustvedt]

The whole right panel is assembled now. 8,45 kg is a bit much, but we'll see how the rest of the body fares. The other side will be much lighter due to no door pieces.

 

[StudEbiker]

Wow, I am so impressed with your build so far.

 

[tahustvedt]

Here's what I made yesterday. Four hours of milling.

 

[StudEbiker]

Any chance you are going to make the files available and/or do some kind of instructable?

 

[tahustvedt]

Sorry, I probably won't do that. I have seen instructions for making coroplast velomobiles though.

 

[tahustvedt]

Front suspension arms. They look short, but there will be ball joints extending from the end.

 

[tahustvedt]

Rear swingarm finished. It's beefy.

 

[recumpence]

This is some of the highest build quality I have ever seen.

Very top notch.

Matt

 

[tahustvedt]

Thanks.

I remember your work from RCGroups back in the days with LMH 120-modifications.

 

[recumpence]

Thanks.

I remember your work from RCGroups back in the days with LMH 120-modifications.

seriously? Wow, that really beings me back. I still have a collective LMH that I fly periodically.

Matt

 

[tahustvedt]

I also remember you electrified a recumbent bike with an Axi.

This is one of my home built helis from those days. Maybe you remember it.

 

[recumpence]

I also remember you electrified a recumbent bike with an Axi.

This is one of my home built helis from those days. Maybe you remember it.

That looks familiar.

My recumbent started the whole RC motored ebike thing. There was another guy on Whales that built an RC motored recumbent at the same time I built mine. But we never knew about each other until we were both finished.

I was invited to this forum based on my recumbent build blog on recumbents.com

There are a few other ebike guys here who remember those days on rcgroups. There are a few guys on the electric skateboard forum here that I knew from rc groups as well. I even ran across one guy here who remembered me from my competition car audio days, then rc groups, now here on the ebike forum.

It is truly a small world.

Matt

 

[Warren]

Don't forget John Tetz' low power trike setup. I was on several big group rides with him and his gorgeous streamliners almost 20 years ago.

 

[tahustvedt]

At least the front suspension is pretty lightweight. 2200 g total weight for the pictured assembly. It's only missing the tube, tire and disc. I'm going to use folding 35mm Kojak tires. The internal rim width is 21 mm.

 

[tahustvedt]

I made some progress in the last week. The cabin is strong enough to work as a monocoque structure. I'm considering going that way.

 

[kfong]

Very impressive build. Even the woodwork is exceptional!

 

[magna_503]

Beautiful work!!!

 

[spinningmagnets]

Don't be disappointed by how few have posted in this thread, its just that...it doesn't seem like you need any advice. Everything you've posted so far has been wonderfully designed and expertly produced.

Here's a pic just for fun: