"Offtopic-posts-topic" NSFW

[ramses]

Your "200x hybrid mix" brings up an interesting question.

Is it possible, with only low order, gaseous, or ETG type propellants, to create a pressure that a container made of some arbitrary material cannot hold regardless of it's wall thickness?

[MrCrowley]

I find most everything delivered by the "Electronic Box of Truth" to be annoying... with the exception of the History Channel. I prefer British narration of WWII history films as they provide a strictly factual narration without adding any undue emotion and drama.

Ah I agree with you on that one. Also, I find that old doco's and books written about WW2 are far better than modern ones. If you've never read a book by Cornelius Ryan (Longest Day, The Last Battle, A Bridge Too Far), I would recommend doing so immediately. He puts authors like Antony Beevor (who has questionable facts in his writtings and they're really quite dull) to shame.

[Zeus]

In theory, if the pressure isn't infinite, a container can hold it, in reality such containers are impractical.

However I'm not paid to speculate, I think a few people here could answer your question.

inonickname, are you on APC chat at a certain time, I'd like to discuss your 200X mix hybrid?

[Selador]

but yes, I think he means that

That what ???

Your pretend cigarette, or my super-duper spudgun ?

[jackssmirkingrevenge]

Your pretend cigarette, or my super-duper spudgun ?

[Selador]

'Eh ???

Yesterday, using my incredispudgun, I shot a 60 pound pure unobtanium dibble-slotted cankbullet.

It completely tore down the railroad bridge.

Redirected the river. (I sure am going to miss looking at those falls.)

Built me a log cabin.

Then barbequed half a pig for my supper.

Let's see your fake cigarillo do that !!!

[velocity3x]

IMO, this is one of the most beautiful aircraft to ever take to the sky. She was heavy and comparatively clumsy but, had an extreme over abundance of power. The F-4 proves that anything can fly if enough power is applied to its arse! Much like launching spuds, I suppose.

[POLAND_SPUD]

hey, remember that guy from Belarus or Ukraine who build an ethanol fuelled combustion?
Do you think it is possible to convert that kind of combustion into a hybrid??

[saefroch]

I'd say probably not, because ethanol has a vapor pressure at room temperature of about .8 psi.

[inonickname]

Your "200x hybrid mix" brings up an interesting question.

Is it possible, with only low order, gaseous, or ETG type propellants, to create a pressure that a container made of some arbitrary material cannot hold regardless of it's wall thickness?

ETG, maybe. Some low orders, maybe. Once your chamber pressure exceeds the absolute tensile/yield strength of the material you begin relying on the chambers inertia to contain it. Assumedly, if you continually exceed it's tensile strength (in my case, by a factor of 10 or more) it will fail eventually. Thicker walls won't change the properties of the material itself.

By the way, "200x hybrid mix" is used rather tongue-in-cheek.

[MrCrowley]

Building an ETG...not exactly brain surgery is it?

[jackssmirkingrevenge]

not exactly brain surgery is it?

I love that sketch, so predictable but the delivery is flawless

IMO, this is one of the most beautiful aircraft to ever take to the sky.

This was my childhood favourite:

Let's see your fake cigarillo do that!

I'm quite liking it, shame on you for mocking my attempts to stay healthy

[Selador]

I'm quite liking it, shame on you for mocking my attempts to stay healthy

I'm not mocking your attempts to stay healthy.

I'm actually quite surprised that no one has joined in on the "Paul Bunyon of spudgun testomonies".

[Technician1002]

I was thinking about this post.. in theory.

Is it possible, with only low order, gaseous, or ETG type propellants, to create a pressure that a container made of some arbitrary material cannot hold regardless of it's wall thickness?

In theory a container can be built for any pressure. If it is built in layers, and each layer is pre-stressed for a certain pressure, than the number of shells and the added layer pressure could hold the pressure.

The difficulty is if the container is needed to hold a dynamic load instead of a static load. If you let the pressure out of the center container, the pre stress pressure on the layers outside it may cause collapse of the inner container.

I had played with design on an earlier PVC only contest. If for example you built an air cannon inside a pressure chamber which was inside another air chamber, it could be filled for a single high pressure shot.

For example, if each chamber can safely hold a max of 100 PSI, then a 6 inch chamber at 100 PSI can hold a 4 inch chamber at 200 PSI, which can hold a 2 inch chamber at 300 PSI which can hold a 1.5 inch chamber at 400 PSI and finally a 1 inch chamber at 500 PSI. The difficulty is the great possibility of failure of the inner chamber when it is fired.

In theory, a chamber can be built to hold any static pressure. Due to changes in stress, I have my doubts on a dynamic pressure spike.

[Fnord]

Another thing to consider with dynamic loads is the speed of the pressure wave. I'm pretty sure once you exceed the speed of sound in your chamber material it'll start behaving more like a liquid than a solid.
You'd be better off using a chamber that has a high elastic deformation tolerance or one that can be easily reformed without fatigue. I don't know what materials would be useful for that, though.

*****

Also, yes, everything on american tv is flashy and over-hyped. Especially news and sports. I think it's because life in general over here is really boring.
I just watch news and sports highlights when something funny or weird happens. I never played sports in school. The only one I actually liked was dodgeball . Now I guess school boards are trying to ban it. I guess it's too violent for them or something
*****

I have a not-quite-off-topic question to throw out there;
What's with the lack of builds coming in lately? It seems like JSR is running the forum by himself anymore. A quick glance at the showcases and it looks like a good bit of the front-page submissions are old bump-ups.
Back when I first joined it seems like there was a steady flow of stuff showing up; and a fair amount was actually pretty good.