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Search found 1498 matches

by Walter
Fri Jul 05, 2019 5:28 pm
Forum: Flycasting Physics
Topic: Thank you!
Replies: 24
Views: 3816

Re: Thank you!

Viking Lars wrote:
Fri Jul 05, 2019 5:20 pm
the rich library of papers dealing with the physics of casting
I for one wouldn't mind a thread with links to online ressources covering the above. Could that be an idea?

Lars
I second that. I know many of these papers aren’t free but maybe SL could start a library with paid access...
by Walter
Thu Jul 04, 2019 10:01 pm
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

Gordy,

You have it half right...ish. You provide examples of converting velocities between frames and then say that the transform only applies to position and not velocity???

Maybe if you think of velocity as a change of position it will be clearer.
by Walter
Thu Jul 04, 2019 7:19 pm
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

Or does it cause the bottom most part of a rolling wheel not to displace air around that part of the wheel, effectively "cancelling" form drag there? Dirk and Graeme, Figuring out the form drag on the cycloid-like path of a small section of line in an earth frame would be a daunting task. Consequen...
by Walter
Thu Jul 04, 2019 7:11 pm
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

Hopefully that makes it a bit clearer. The velocity profile of a rolling wheel is one of those counterintuitive things you come across in physics. Hi Walter I don't know how to put this more clearly than I have been. The velocity profile of A POINT ON a rolling wheel (cycloid path and all that) is ...
by Walter
Tue Jul 02, 2019 7:32 pm
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

1. Don't confuse linear motion with angular motion. There is a component of air drag evenly spread around the wheel due to the spinning motion of the wheel. I believe this is being called skin drag on this forum. The form drag is directly related to the motion of an object relative to air and if th...
by Walter
Tue Jul 02, 2019 5:08 pm
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

Hi all Not arguing for or against lift, just pondering the implications of a point on line in the lower part of the loop having basically zero velocity (tethered cast) - As a car drives, does the close-to-road-surface part of its wheels involve close to zero air drag because a point on the tread in...
by Walter
Tue Jul 02, 2019 3:21 pm
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

Another nice video Graeme. I think that’s what we call a parachute cast. Again, nothing to do with aerodynamics that I’m aware of.
by Walter
Tue Jul 02, 2019 12:03 pm
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

Can anyone cite a paper studying the use of form drag induced lift from the aeronautics world? Graeme, Try this https://www.leshatton.org/Documents/AW_JavelinArticle_1105.pdf This doesn’t mean I support the idea that the bit of line at the bottom edge of the loop is keeping the line aloft like the ...
by Walter
Tue Jul 02, 2019 4:29 am
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

30 20 1216.98% Walter, It looks like you have a factor of 2 difference in your normal force values compared to Torsten's. Also you need to multiple the Fn values by cosd(angle) to get the vertical lift component of Fn so it can be compared to downward Fg weight and thus get a true Fy/Fg ratio. Gord...
by Walter
Tue Jul 02, 2019 12:38 am
Forum: Flycasting Physics
Topic: Lift force acting on a fly line
Replies: 321
Views: 25202

Re: Lift force acting on a fly line

Hi, have updated the table, Gordy has mentioned the Reynolds number, I've included that and the ratio for the lift component as well, slightly lower density. The influence of the Reynolds number isn't that big, because Re is in the range > 100 for the fly line example above 1 m/s. Please check, if ...

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