Source, please?What isnt generaly known is that certain spiders ilks have the highest heat conductivity of any material in existance.
Was working from memory,and will see if I can backtrack to the published article and data if its not paywalled.Source, please?
I found one study by one researcher on silk from one species of spider that reported surprisingly high levels of thermal conductivity: much higher than other organic materials, about as good as copper (which is very high), and not as good as silver, graphite, etc. The spider silk is about 25% as thermally conductive as diamond. But, yeah, if this guy's measurements are right, spider silk might be a very good conductor of heat. Magazine piece on the study.
There will certainly be improvements in belts and other materials in time. The available products will be bounded by economics (i.e. what the market demands and will pay for, not what is technically possible) just like everything else. Maybe spiders will work pretty cheap, we can just keep supplying juicy flies.
Just like a rubber band heats up when stretched.Didnt find a reference to the exact claim I mentioned about spider silk,but found something else which is real interesting,which is that when spider silk is stretched,the rebound is dampened because some of the
mechanical energy of stretching is released as heat as it returns to its original length.
Spider silk is a kind of natural biomaterial with superior performance. Its mechanical properties and biocompatibility are incomparable with those of other natural and artificial materials. This article first summarizes the structure and the characteristics of natural spider silk. It shows the...www.degruyter.com
Ok.Just like a rubber band heats up when stretched.
The stretch of spider silk would seem to make it less useful as a belt fiber than existing fibers. For a belt, we do not want a fiber that elongates a lot under load, adding heat to the belt as it expands and contracts.
To get back to the subject at hand: The existing aramid belt fibers are demonstrating that they are up to the task, if loads are kept reasonable. If loads aren't reasonable, then a "super belt" won't help if resonance, TV, etc loads are simply transferred to another susceptible part
Is there an airframe-specific reason to do it that way? What sort of aircraft is this anyway?I plan to mount the engine and drivetrain like on a BD-5....
You should not use it. It's just 20 year old data on my hard drive, and it may have been an early guess. Determine the stiffness of the belt you have on hand, or a suitable replacement. That means a test rig in your shop, which will probably take the form of angle vs load, just like any other stiffness, or manufacturer data. They have it.The only number that I used directly from your most recent list was the stiffness of the belt.
Your friction clutch setup is nothing like Jeron's, which was located near the first node, in parallel with the soft element, and purposely made of a material which minimized the delta between static and dynamic friction.My hope is that the friction clutch against the flywheel will give me the same result as Jeron had with his dry friction surface in the upper shaft.
Yes...if you intend to keep it.I am using the friction part of a factory Chevy Metro clutch. This has springs in it. Do I calculate these in like a stiffness?
The Shore scale is not a measure of torsional stiffnessAlso does anyone have a figure for Shor A stiffness?
Probably because it was designed to be a coupler, not a torsional soft element. It has a torsional stiffness value of course, but nobody intended it as an engineered stiffness product. Lovejoy makes a variety of products that are, so maybe it's time to look at them.My Lovejoy spider talks about angular limits but does not provide any torsional stiffness numbers.
That's the idea. Keep moving those stiffness and inertia values to different locations in the system. Then explore some different values.Played with Holzer this morning. If you read what both Billski and DanH have written here (and VAF for DanH) then play with the same numbers it is very educational.
A two-plate style drive purchased from Reductions Inc, in Canada. Circa 1996, advertised as "fully tested", complete with video of test stand running...which in retrospect, didn't include any footage while running at the resonant RPM. All in all, it was a torsional and mechanical disaster. Long gone I think. Back then auto conversions were the wild, wild West.DanH had a belt come apart in flight while doing touch and goes which ran his drive through the worst part of his frequency range multiple times.
Focus. Conceptual design first, then explore frequency while re-arranging stiffness and inertia values which fit the conceptual profile. Get the resonant frequencies out of the operating range, and amplification becomes a non-issue.I think it is time to play with minimizing amplification.