Go Back   EcoModder Forum > EcoModding > Aerodynamics
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 04-14-2015, 05:14 PM   #11 (permalink)
Master EcoModder
 
Join Date: Feb 2010
Location: Elmira, NY
Posts: 1,781
Thanks: 319
Thanked 355 Times in 297 Posts
The lower leg fairings are definitely worth developing. Upright Mike at recumbents.com has experimented with them and I have used barn boots in winter as well. The upper torso boat tail is also a proven design. The FIM limits its size on motorcycles and Triathlon sanctioning bodies have outlawed aero devices attached to clothing. A front aero water tank is permitted up to a given size. No ruling an rear water/food carriers yet.

The older gentlemen at the Vetter Challenge prefer a back angle close to vertical or slightly reclined. More progress is being made so check the latest post at craigvetter.com.

A bicycle fairing will be very similar in shape to the motorcycle fairing and 7/8 the size usually. The trick with a aero tuck is to have good fit and support of the chest and fore arms to reduce fatigue. I use a full face helmet with visor but a 'spaceman' bubble may prove undesirable when pedaling in warm weather. Anything over 30 mph (50kph) and I may install a lap belt plus skid plates in the fairing for my hips and shoulders.

  Reply With Quote
The Following User Says Thank You to Grant-53 For This Useful Post:
aerohead (04-14-2015)
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 04-14-2015, 05:25 PM   #12 (permalink)
T-100 Road Warrior
 
BamZipPow's Avatar
 
Join Date: Apr 2008
Location: The Woodlands, TX
Posts: 1,920

BZP T-100 (2010) - '98 Toyota T-100 ext cab - 3.4L/auto SR5
Last 3: 24 mpg (US)

BZP T-100 (2011) - '98 Toyota T-100 ext cab - 3.4L/auto SR5
Last 3: 23.66 mpg (US)

BZP T-100 (2009) - '98 Toyota T-100 ext cab - 3.4L/auto SR5
Last 3: 19.01 mpg (US)

BZP T-100 (2012) - '98 Toyota T-100 ext cab - 3.4L/auto SR5
Last 3: 25.45 mpg (US)

BZP T-100 (2013) - '98 Toyota T-100 SR5
Last 3: 25.79 mpg (US)

BZP T-100 (2014) - '98 Toyota T-100 SR5
Last 3: 23.18 mpg (US)

BZP T-100 (2015) - '98 Toyota T-100 SR5
Last 3: 23.85 mpg (US)

BZP T-100 (2016) - '98 Toyota T-100 SR5
Last 3: 17.62 mpg (US)

BZP T-100 (2017) - '98 Toyota T-100 SR5
90 day: 20.78 mpg (US)

BZP T-100 (2018) - '98 Toyota T-100 SR5
90 day: 20.19 mpg (US)

BZP T-100 (2019) - '98 Toyota T-100 SR5

BZP T-100 (2020) - '98 Toyota T-100 SR5

2012 Scion iQ - '12 Scion iQ Base
Thanks: 3,479
Thanked 1,395 Times in 968 Posts
Send a message via ICQ to BamZipPow
Wink

Quote:
Originally Posted by parabellum View Post
BamZipPow, thanks for the greeting. I have my account for a few years but I wasn't too active here, though.

It sounds like putting a well-fitted windshield can lower the power output by several watts, now I have to do it myself and check if it works that well for me (I ride almost only in the touring position, I don't do any racings).

These upper wheel fairing are really expensive, maybe doing your own fairing that are integrated with fenders and enclose the whole wheel (with cuts for brakes) would be a cheaper way?


Rumdog, I've seen that some of the pizza delivery men riding on scooters have rucksacks in a prolonged shape, maybe that would be a good base for making a kamback pack

Grant-53, I will surely make the read about the tail box, I'm riding upright so I have to check if it will work well in that configuration.
You could try building those items out of extruded foam/Foamular. It makes a fantastic platform to experiment with and you can easily shape fer yer needs. If you want to go even further, you will have a shape that you built to work from.
__________________
Dark Aero-The world's first aerodynamic single wheel boat tail!

  Reply With Quote
The Following User Says Thank You to BamZipPow For This Useful Post:
aerohead (04-14-2015)
Old 04-14-2015, 05:27 PM   #13 (permalink)
PSmodder lurker
 
Join Date: Jan 2009
Location: Chino
Posts: 1,605
Thanks: 26
Thanked 908 Times in 522 Posts
Minimum prep, aero refitting yourself to the bike. Time trial bike aero tips for more efficient road bike riding.

Duathlon Triathlon bike fitting

http://a2wt.com/research.pdf

Ways to improve aerodynamics for timetrials -

Biggest Bang For Your Buck In Time Trial Equipment | CyclingTips
  Reply With Quote
The Following 2 Users Say Thank You to botsapper For This Useful Post:
aerohead (04-14-2015), COcyclist (05-07-2015)
Old 04-14-2015, 10:40 PM   #14 (permalink)
Moderator
 
Vman455's Avatar
 
Join Date: Feb 2012
Location: Urbana, IL
Posts: 1,935

Pope Pious the Prius - '13 Toyota Prius Two
Team Toyota
SUV
90 day: 51.62 mpg (US)

Tycho the Truck - '91 Toyota Pickup DLX 4WD
90 day: 22.22 mpg (US)
Thanks: 198
Thanked 1,797 Times in 937 Posts
Quote:
Originally Posted by BamZipPow View Post
How on earth do those weigh 2 pounds?
__________________
UIUC Aerospace Engineering
www.amateuraerodynamics.com
  Reply With Quote
Old 04-14-2015, 11:23 PM   #15 (permalink)
T-100 Road Warrior
 
BamZipPow's Avatar
 
Join Date: Apr 2008
Location: The Woodlands, TX
Posts: 1,920

BZP T-100 (2010) - '98 Toyota T-100 ext cab - 3.4L/auto SR5
Last 3: 24 mpg (US)

BZP T-100 (2011) - '98 Toyota T-100 ext cab - 3.4L/auto SR5
Last 3: 23.66 mpg (US)

BZP T-100 (2009) - '98 Toyota T-100 ext cab - 3.4L/auto SR5
Last 3: 19.01 mpg (US)

BZP T-100 (2012) - '98 Toyota T-100 ext cab - 3.4L/auto SR5
Last 3: 25.45 mpg (US)

BZP T-100 (2013) - '98 Toyota T-100 SR5
Last 3: 25.79 mpg (US)

BZP T-100 (2014) - '98 Toyota T-100 SR5
Last 3: 23.18 mpg (US)

BZP T-100 (2015) - '98 Toyota T-100 SR5
Last 3: 23.85 mpg (US)

BZP T-100 (2016) - '98 Toyota T-100 SR5
Last 3: 17.62 mpg (US)

BZP T-100 (2017) - '98 Toyota T-100 SR5
90 day: 20.78 mpg (US)

BZP T-100 (2018) - '98 Toyota T-100 SR5
90 day: 20.19 mpg (US)

BZP T-100 (2019) - '98 Toyota T-100 SR5

BZP T-100 (2020) - '98 Toyota T-100 SR5

2012 Scion iQ - '12 Scion iQ Base
Thanks: 3,479
Thanked 1,395 Times in 968 Posts
Send a message via ICQ to BamZipPow
Wink

Quote:
Originally Posted by Vman455 View Post
How on earth do those weigh 2 pounds?
Probably from all the metall hardware...
__________________
Dark Aero-The world's first aerodynamic single wheel boat tail!


Last edited by BamZipPow; 04-15-2015 at 08:25 AM..
  Reply With Quote
Old 04-15-2015, 08:34 AM   #16 (permalink)
Master Novice
 
elhigh's Avatar
 
Join Date: Jan 2008
Location: SE USA - East Tennessee
Posts: 2,314

Josie - '87 Toyota Pickup
90 day: 40.02 mpg (US)

Felicia - '09 Toyota Prius Base
90 day: 49.01 mpg (US)
Thanks: 427
Thanked 616 Times in 450 Posts
Quote:
Originally Posted by BamZipPow View Post
Probably from all the metall hardware...
I was thinking that between the added weight, the added stuff sticking into the wind in the mounting hardware, and the minimal coverage, those little skirts probably aren't helping much.

Parabellum, filling in the main triangle of your bike's frame is a good idea for minimal investment, just to feel how it might improve things. That is, unless you want to retain your water bottle mount. Or that's where some people clip a battery for a headlight.

Based on my limited experience of a stationary bike vs. my vast experience on actual bikes, try not to limit your exposure to moving air too much. If you build a fairing to cover most of yourself and the bike, leave a couple of ducts open here and there to provide a breeze on you. Even at modest rates of exercise you'll build up a lot of heat and if you don't have any airflow, you'll be pretty overheated pretty quickly.

One flow of air directed toward your chest and another at your groin will make a big difference in your overall comfort level, but that's a matter of personal preference.
__________________




Lead or follow. Either is fine.
  Reply With Quote
The Following 2 Users Say Thank You to elhigh For This Useful Post:
aerohead (04-15-2015), Grant-53 (04-15-2015)
Old 04-15-2015, 01:45 PM   #17 (permalink)
Moderator
 
Vman455's Avatar
 
Join Date: Feb 2012
Location: Urbana, IL
Posts: 1,935

Pope Pious the Prius - '13 Toyota Prius Two
Team Toyota
SUV
90 day: 51.62 mpg (US)

Tycho the Truck - '91 Toyota Pickup DLX 4WD
90 day: 22.22 mpg (US)
Thanks: 198
Thanked 1,797 Times in 937 Posts
Quote:
Originally Posted by BamZipPow View Post
Probably from all the metall hardware...
There isn't that much to it, though--I count eight bolts, two rods, four plates, and the fairings themselves. To compare, this wheel:



...which is an aluminum box-section rim with a fairly substantial fairing, weighs just over two pounds.

Also, he shouldn't be claiming "up to 20 percent faster without any extra effort," when there was no controlled testing to generate that number.
__________________
UIUC Aerospace Engineering
www.amateuraerodynamics.com
  Reply With Quote
Old 04-15-2015, 02:05 PM   #18 (permalink)
Master EcoModder
 
3-Wheeler's Avatar
 
Join Date: Dec 2008
Location: Southern WI
Posts: 827

AlienMobile - '00 Honda Insight
Team Honda
90 day: 80.05 mpg (US)
Thanks: 101
Thanked 560 Times in 191 Posts
Quote:
Originally Posted by aerohead View Post
.... This is something the Craig Vetter gang is missing on the Motorcycle Forum......
Phil,

Just curious. Has anyone from EcoM ever written to Craig and mentioned the Streamlining Template to him?

I noticed that many of the CV fairings, drop quickly behind the rider. And there is a reference to a aero specialist that gave mention of making the rake even steeper.

I'm at a loss on some of the things I've seen there. The overall premise of an airfoil around the rider is great however, and he gives great ideas on how to mount them.

Jim.
  Reply With Quote
Old 04-15-2015, 06:12 PM   #19 (permalink)
Aero Wannabe
 
COcyclist's Avatar
 
Join Date: Dec 2007
Location: NW Colo
Posts: 738

TDi - '04 VW Golf
TEAM VW AUDI Group
90 day: 53.2 mpg (US)
Thanks: 705
Thanked 218 Times in 169 Posts
Quote:
Originally Posted by parabellum View Post
I would like to ask if there are any aerodynamic modifications that would do any good for a typical bicycle (in my case this is a diamond frame)?
Parabellum, I have been a bike commuter for roughly 40 years and an avid cyclist for much of that time. In my experience, anything you do to a diamond frame bicycle will have minimal effect on your commute times. I commute year round wearing bulky, baggy clothes in winter. The biggest drag comes from the rider. If you can get your upper body low and your back level with the ground that will make the biggest difference. You will decrease your CdA so a drop bar may be better than a flat handlebar. An "aero-bar" may get you even flatter but it is not practical to ride that way in traffic.

Anything you add to the bike may help in some ideal conditions but be a hindrance in everyday use. Bicycles are much more influenced by a crosswinds than are motorcycles. A 20 mph crosswind on a bicycle at 15 mps still feels like a nasty crosswind. A 20 mph crosswind at 60 mph on a motorcycle acts like mostly a headwind. Sailors talk of apparent wind, physicists speak in terms of vectors but you get the point. Many of the things that work for motorcycles could make you slower in the real world. Save up and build a tadpole trike velomobile as the ultimate commuter bike (or Human Powered Vehicle).
__________________
60 mpg hwy highest, 50+mpg lifetime
TDi=fast frugal fun
https://ecomodder.com/forum/showthre...tml#post621801


Quote:
Originally Posted by freebeard View Post
The power needed to push an object through a fluid increases as the cube of the velocity. Mechanical friction increases as the square, so increasing speed requires progressively more power.

Last edited by COcyclist; 04-16-2015 at 04:56 PM..
  Reply With Quote
Old 04-15-2015, 06:44 PM   #20 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 15,861
Thanks: 23,922
Thanked 7,207 Times in 4,640 Posts
Template

Quote:
Originally Posted by 3-Wheeler View Post
Phil,

Just curious. Has anyone from EcoM ever written to Craig and mentioned the Streamlining Template to him?

I noticed that many of the CV fairings, drop quickly behind the rider. And there is a reference to a aero specialist that gave mention of making the rake even steeper.

I'm at a loss on some of the things I've seen there. The overall premise of an airfoil around the rider is great however, and he gives great ideas on how to mount them.

Jim.
I'm not sure for certain.
When Low & Slow came by a few years ago we talked about MC aero quite a bit and Vic is acquainted with the Template and also a friend of Craig's.
So I figure Craig has at least been exposed to it.
I think Craig has used symmetrical wing sections as a template,and I think it's more appropriate for bikes.
And with these 2-D flow shapes,we don't want to truncate them as we would a body of revolution.Any kind of pointed curve in the aft-body is better than a chop-off.
The Summers Brother's Goldenrod would be a good example.Walter Korff,who did the aero on this record car,found the tail so important that he enclosed the parachute tubes entirely inside a boat-tailed cone which could be shot off the car as a prelude to parachute deployment.
Last September,at Bonneville I was happy to see the Vesco family streamliner with this feature added finally,along with a few other teams.
I feel like Craig and his associates are on top of MC aero and have done well with their designs.
Here's one example of the clamshell rear

This bike would suffer larger drag with it's truncated tail

Here's the lowest drag 2D profile (in the center)

This table gives an idea for drag penalty when the tail is mutilated


__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/

Last edited by aerohead; 04-15-2015 at 06:50 PM.. Reason: add image
  Reply With Quote
The Following 5 Users Say Thank You to aerohead For This Useful Post:
3-Wheeler (04-16-2015), BamZipPow (04-15-2015), Fat Charlie (04-17-2015), mikeyjd (04-15-2015), rumdog (04-16-2015)
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com