J
Joe Riel
Guest
[email protected] writes:
> Joe Riel writes:
>
>> www.k-online.com/~joer/cycling/spoke-tension.pdf
>
>
> I think the inflexible rim assumption distorts this graph. The
> flexibility of the rim is seen in deflection plots in "the Bicycle
> Wheel" and these are roughly valid for tension increases on the order
> of the tension reductions by radial loading. Rim deflections are
> relatively large and the cosine effect of displacing the spoke center
> when manually squeezing is in that range. Therefore, the resulting
> over-tension is probably less than computed.
Possibly the graph wasn't clear (i.e. I didn't assume a rigid rim, but
did assume that any deflection would be in the plane of the wheel).
There are several plots in the graph, each for a different rim
stiffness (the Kl term is a computed loop stiffness, given in eq 11).
The upper plot is for a rigid rim, I included it to show the predicted
upper limit (for 1.8 mm spokes). The range of values of rim stiffness
were taken from Gavin's paper; the middle range of Gavin's numbers
were consistent with values extracted from your finite element data.
Joe
> Joe Riel writes:
>
>> www.k-online.com/~joer/cycling/spoke-tension.pdf
>
>
> I think the inflexible rim assumption distorts this graph. The
> flexibility of the rim is seen in deflection plots in "the Bicycle
> Wheel" and these are roughly valid for tension increases on the order
> of the tension reductions by radial loading. Rim deflections are
> relatively large and the cosine effect of displacing the spoke center
> when manually squeezing is in that range. Therefore, the resulting
> over-tension is probably less than computed.
Possibly the graph wasn't clear (i.e. I didn't assume a rigid rim, but
did assume that any deflection would be in the plane of the wheel).
There are several plots in the graph, each for a different rim
stiffness (the Kl term is a computed loop stiffness, given in eq 11).
The upper plot is for a rigid rim, I included it to show the predicted
upper limit (for 1.8 mm spokes). The range of values of rim stiffness
were taken from Gavin's paper; the middle range of Gavin's numbers
were consistent with values extracted from your finite element data.
Joe
