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Old 02-15-2022, 06:57 PM   #41 (permalink)
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Quote:
Too complex?
Possibly. The trailing arm is one A-arm, the tailbox is the second. One dog-bone link?

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Old 02-16-2022, 10:52 AM   #42 (permalink)
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Quote:
Originally Posted by The Toecutter View Post
If you attempted to put an image in your last post, it is not visible.
Here it goes:



Side note: initially these "strakes" i attached to the back had a positive efect, especially whe the wind was sideways from the front. Now, with the canopy, that has changed - the bike has become a bit slower.

And again: there are many more aerodynamic issues with that VM, an possibly even more important ones (at least according to Daniel Fenn, the maker of many of the fastes racing velomobiles including the one holding the 24h world record for women. Initially Daniel had raced a GoOne 3, so he knows that bike quite well).

One which might be important is the question what do do with the air coming in from the open side windows of the canopy? Cut holes into the back? Will that also reduce the wake?

Last edited by beate; 02-16-2022 at 11:18 AM..
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Old 02-16-2022, 11:40 AM   #43 (permalink)
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cutting holes

Quote:
Originally Posted by beate View Post
Here it goes:



Side note: initially these "strakes" i attached to the back had a positive efect, especially whe the wind was sideways from the front. Now, with the canopy, that has changed - the bike has become a bit slower.

And again: there are many more aerodynamic issues with that VM, an possibly even more important ones (at least according to Daniel Fenn, the maker of many of the fastes racing velomobiles including the one holding the 24h world record for women. Initially Daniel had raced a GoOne 3, so he knows that bike quite well).

One which might be important is the question what do do with the air coming in from the open side windows of the canopy? Cut holes into the back? Will that also reduce the wake?
If you open a pathway, between the side windows and wake, there's a high probability that you'll experience reversion, with wake air flowing forwards to the low pressure of the widened body section.
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Old 02-16-2022, 12:23 PM   #44 (permalink)
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Further to my point at #37, the triangular gusset would be a good location for an upper pivot point.
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Old 02-16-2022, 02:37 PM   #45 (permalink)
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You mean someting like that?

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Old 02-16-2022, 03:06 PM   #46 (permalink)
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That looks like a single swing arm. I guess I'm thinking of a tail box that moves up and down instead of pivoting.

But feel free to ignore my comments. Here's a picture I drew in the 1970s of an open-cockpit variable wheelbase motor home.



Don't ask me to explain that exhaust system today.
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Old 02-16-2022, 03:55 PM   #47 (permalink)
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I do not think that this would have a positive effect on the flow. Surface too uneven.

I noticed with a door of my car damaged by an accident, and i noticed with my bike as well:


That canopy will slow down the bike compared to full cabrio mode, while the smooth GFK-Canopies improve aerodynamics.

BTW: Your sketch reminds me to that one:

https://www.velomobilforum.de/forum/...76ef9b14e2c695

(no swing arm, suspension completely removed - that one has now been converted into an E-Bike)
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Old 02-16-2022, 04:43 PM   #48 (permalink)
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Quote:
Originally Posted by beate View Post
[nurl]https://www.velomobilforum.de/forum/proxy.php?image=https%3A%2F%2Fi.ebayimg.com%2Fimag es%2Fg%2F4ugAAOSws-1cuXyk%2Fs-l1600.jpg&hash=c25b635bf5c8fe106976ef9b14e2c695[/nurl]
Fails to load. Throw a tonneau cover over that rack and snap it to the trailing arm. Done.
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Old 02-16-2022, 08:04 PM   #49 (permalink)
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Ok, thatz one should hopefully load:

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Old 03-04-2022, 03:56 PM   #50 (permalink)
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Back to the general thread. Aerydynamics.

The canopy has a very noticeable effect: almost no air movement in front my face, nothing on the sides, but strong vortices in the neck, starting behing the ears. Indepent on the back.

What's going on. More important: how to deal with such a flow. Do i need to open the back plate?

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