Wheels out velomobile design with Cd of 0.28

I have now achieved a Cd of 0.28 for the wheels out design. This should lead to a CdA of between 0.09 - 0.11 depending on final configuration. This design is a lot more practical while still being as aerodynamic as other production velomobiles. Chassis is well under way and will be finished before 2019. I am constantly having to keep tp my design goals which are...
• Low weight (under 22kg)
• Lower cost of production (hope to be under €2500 or US$3000)
• Safety (some crash protection)
• Practical everyday use velomobile.

Velomobile in virtual windtunnel

Veloci-velo in virtual wind tunnel at 32 km/hr (20 mph). At this speed the cdA= 0.08, with further tweaking this could be reduced but will do the fine tuning on working prototype using wool tufts and video footage. In combination with lightweight chassis (under 22kg) I hope this velomobile will be competitive in average speed with more performance biased velomobiles such as the DF and the WAW but at a significantly lower cost.

Veloci-velo design philosophy

veloci velomobile ©2018

The design philosophy for this velomobile are low vehicular mass, aerodynamics, ease of manufacture, cost and minimal environmental impact.

Main benefits are...

• Non-polluting - 65% of all carbon monoxide emitted into the environmental is from road vehicles.   Veloci-velo is a Zero Emission Vehicle.
• Healthy and Fun - Easier than riding a bike, get fit commuting, shopping or just out cruising.
• Easy to park and store - Requires no wall or object to lean it against, takes up less than 1/6 loadspace of average automobile.
• Secure and safe - Stable and nimble tadpole trike design. Built in frontal crumple zone.

To understand my vision you really need to understand the problem...
The problem with most of todays personal transport options comes down to one thing - MASS!
Everyday 66% of vehicle journeys are under 6km in distance are taken by just one person!
This seems incredible especially when drawn to the fact that the single occupant only makes up 2-8% of the total mass being transported. So why do we need a 1000+ kg machine to transport one person such short distances? Is it for convenience sake?

Common chassis open or enclosed wheels

The great thing about designing my own velomobile is that I can have one of two options for the bodyshell. I can have an open wheel design like the one on the left or an enclosed version on the right. Both use the same chassis. The advantage for speed goes with the enclosed version, but style and practicality the winner has to be the open wheel design velomobile. What's your favourite?

Noise inside a velomobile

From my experience in riding velomobiles I have found one of the most irritating aspects to be the amount of noise (rumbling) when inside a moving velomobile. All this noise adds up to rider fatigue and makes the velomobile annoying to use when compared to a diamond frame bicycle.

Commercial fiberglass or carbon fibre monocoques are hollow tubes that echo like a drum with all the drivetrain and road on tyre noise as well as the suspension noise being transmitted to the rider.

Quest Velomobile Fiberglass Monocoque 

Solutions? I really like the foam shells of John Tetz the only issue with this construction method is the labour involved and the shell only provides limited crash worthiness. But it is lightweight and noise would be minimal due to the sound absorbing properties of the foam.

John Tetz Foamshell

Another great design is this Softshell concept velomobile has been made by Czech designer Martin Miklica. This approach would mitigate noise but if the fabric is too tight it may cause a drum effect.

Martin Miklica Softshell

Of course there are other solutions such as used in the car industry such as acoustic soundproofing, rubber mounted sub chassis etc. etc. but this approach always adds weight which is undesirable in a velomobile. Maybe even an approach of using all three of the above for one design could be a way of making riding a velomobile a quieter experience?

Quality renders of open wheel velomobile

The case against Carbon Fiber!

https://www.outsideonline.com/2261721/dirty-secret-hiding-your-high-end-mountain-bike?utm_content=buffer12110&utm_medium=social&utm_source=twitter&utm_campaign=tweet

Open wheel Velomobile

On my previous post "F1 inspiration" I tested a open wheel design which surprised me with it's aero efficiency. I decided to model this up a bit more in detail with some of the renders below.

What I really like about this design is its simplicity, ease of construction and ingress and egress would be very much easier than a wheels in design.

I can see many benefits especially I think this type of velomobile design would be more accepted by the general public as still being a "bicycle".

F1 inspiration

I have been looking at single seat race cars for inspiration and although F1 cars have really bad CdA figures that is in part due for the need to have huge downforce and air intakes to cool a high output power plant.
The F1 tub by itself has to protect the driver but also allow the smooth flow of air to the wings, foils and intakes. If we take away these downforce/cooling aids (by the way they are not aerodynamic aids!) we are left with the tub/driver pod.
I quickly modelled up a velomobile with similar design to a F1 tub and put it through the CFD. It made for some astonishing results.
The frontal area calculated out to be 0.32m2 and the Cd was 0.28! put these two together and I got a CdA of just 0.0896 !!!

Although this figure is higher than my older design which had a CdA of 0.07. It really is an interesting comparison and with this "Open Wheel" design it could be made a lot lighter and easier to produce and also have a smaller turning circle. This could be a great design for a practical everyday velomobile.