calbiterol

Welcome back! (Yeah, it's a few weeks late...)

I'll answer these as best as I can.

1. What I meant by this is that the parts of the universe (individual galaxies, etcetera) are receding from each other. Hence, the parts of something infinite are receding from each other. Just a bad way of wording it.

2. I don't remember saying anything about unbounded. But yes, I am using these interchangeably.

3. Expanding (the overall size of the universe) and receding (the parts from each other). Again, a poor choice of words on my part, for which I apologize.

You could google it...

That's about all I can say though, because I am by no means familiar with commercial electolysis of water. I do know that they usually don't electrolysize.

Not a bad idea, but it might actually be cheaper to go with the fire bricks. I was considering hooking up a propane tank, but I think I'd rather just go with the coke. I should be finding some materials this weekend, I'll update you guys then.

Sounds like a trip to Home Depot would do loads of good.

I'd rather just use coke or charcoal, which brings me back to my previous question - got any suggestions of where to acquire some? Coke in particular, if you don't mind.

Instead of using solar cells perse, use parabolic reflectors to drive stirling cycle engines. It's much more efficient and cheaper by far.

Do I understand you to agree with me that space is unbounded?

Not quite sure of your wording, so I'll put it this way. I think the universe is infinite and expanding (receding), and am in agreement with the general scientific community. If that isn't a clear enough answer, let me know and I'll try to further clarify it. Note that as I'm planning on going into aerospace/aeronautical/astronomical engineering, I have somewhat of a responsibility to obey the current laws of physics.

Don't forget, there's a difference between metric tonnes and imperial tons.

I find it funny that everyone (or everyone that I've seen so far) arguing with the original post and against the accepted and (by all means) tried and true model of the universe (I'd like to see one of them try to prove it wrong) all bear the words "Banned" or "Permanently Banned" directly under their names. In all honesty, I did not know some of these people had been exterminated, and felt some satisfaction/relief upon seeing so.

I also find it ironic that this thread continues to live on despite this.

An idea just hit me - would using hydrogen as a fuel be practical? It's relatively easy to obtain and burns at very, very high temps... Or would that be too dangerous?

Not to be nit-picky or anything, but silicon oxide isn't an element. The most common element in the earth's crust, by the way, is oxygen, IIRC.

The problem' date=' as I see it is that escape velocity is what, 11,200 m/s? So even at a constant 3g acceleration your rail gun would be 2131 km long.

 

That'd be expensive... and I don't even want to spitball how much power it would require.[/quote']

First, I'm not sure that everyone will understand how you got that, so I'll post the math for you. Starting with the kinematic equation [math]vf^2 = vi^2 + 2ad[/math], substitute in variables and solve (your escape velocity is correct, in case you weren't sure). So...

[math](11200)^2 = 2 * a * d[/math]

[math]62720000 = a * d[/math]

[math]62720000 / a = d[/math]

 

Substitute in 3g for acceleration and you get around 2131 (mine came out to 2133, but close enough).

 

Now, the average human can take around 2-3 g before passing out. More naturally tolerant humans can take an additional 1 or 2 g before the lights go out. Most pilots in modern air forces are trained to withstand around 10-12 g with some special equipment (g - suits), in particular those filled with a liquid of constant density. I might add that this is exclusively in the headwards direction - the same direction as the constant 1g one experiences when standing. If the subject is exposed to acceleration that is equivalent to the constant 1g experienced while laying down, then the average person can withstand around 10g without any special equipment.

 

If you figure that the pilot/passenger is NOT experiencing acceleration in the headwards direction, and accelerate 10g (for the average human - plus the math is much simpler). This yields 640 kilometers, which is still very, very large. Hence the suggestion to send up living organisms seperately and by other means.

 

Alternatively, this could be used to save on fuel costs instead of completely eliminating them - in other words, burn a very small amount of fuel instead of a very large amount. This would also eliminate the need to overcome static friction, which is responsible for an incredible amount of fuel.

 

[Edit: I thought I might add that electromagnetic forces (just like a railgun) can accelerate 2,000 g (about 20,000 m/s^2) or more, and are not that expensive.]

Yep. Not as hot as that forge is going to be, though.

Took me a second to get what you meant, acidhash, but yeah, that's a great idea - it makes perfect sense. Which stones are you talking about? Just little pebbles? Or are they something in particular? I'll do some materials scouting this weekend and let you guys know what it's gonna look like when I scrounge up some cash, and I'll be sure to keep you updated on my progress - and any suggestions you might have would be cool then, too. I suppose I should ask where a good place to get either coke or charcoal would be, then?

Again, thanks much for all the help.

Will charcoal heat steel and iron to white or red-hot temperatures? I never knew it could be so hot. Just the run-of-the-mill kind, like you would use for a grill? Out of curiosity, what kind of temperatures can plaster of paris withstand?

YT, I'm not in any way worried about being ultra-traditional. Almost anything that makes it more practical or cheaper is fine by me.

What I'm thinking right now is that I'll use bricks or tiles of some sort (probably fire bricks... You say most stores that sell fireplaces will have them?) so that I can reconfigure the furnace for other things - for example, melting copper, bronze, etc in a crucible for detail work and castings, or if I feel like it, just a grand ol' bonfire with some good ol' wood.

Thanks for all the help, it'll definitely do worlds of good.

Would clay tiles work the same way? Well, the more appropriate question is, would they be practical? I can't describe them, other than you can get 'em for a couple US at random home-improvement / building shops.

Where could I obtain coke? How much would it cost me?

Also, could regular coal be used instead? If yeah, would it be any cheaper?

[Edit: wouldn't a high-temperature-tolerant parabolic mirror be better? That way, the center is incredibly hot? Or a combination thereof? I don't know the temps where steel/iron gets white-hot or red-hot, but I do know that aluminum in particular has an incredibly high melting point.

Then again, looking at melting points in particular, that doesn't look like it's going to be feasible, or even possible.]

I've been hit with a wave of revival for my fascination with blacksmithing, and, in particular, sword-smithing and armor-smithing. In order to have any hope in pursuing this interest, I need a furnace (of sorts) that is capable of heating iron, and eventually steel, to red-hot temperatures. I would prefer this to work in conventional means, and not involve the use of gas. In addition, it would be a definite plus if it was of minimal size, which leads me to my question:

If you have any questions, feel free to ask.

Hopefully that wasn't too vague. Thanks in advance,

Calbit

this REALLY does NOT belong here in this thead, DDT does NOT apply to pulse engines in fact if it were to apply to ANY type of engine it would be a Deisel sort (and they don`t fly).

YT, I have to disagree. DDT does not have anything to do with pulsejets, no, BUT the thread was started as an inquiry about pulse detonation engines. Pulse detonation engines use DDT as a method to produce detonation in the engine. In fact, the quote that vrus mentioned was from the wikipedia article on pulse detonation engines. Given all of the above, I would consider it a perfectly valid discussion in this thread.

vrus, as far as sustaining it, they don't, really - hence the pulse part. The repeat the process (up to) thousands of times per second.

Here in California, the power companies have a program whereby a solar panel on your house would feed energy back into the power grid if you generated excess power, so there's no need to get batteries. Excess power you generate and feed into the grid also go into lowering your energy bill, which is a nice bonus.

I would like to add two things. First, the need for batteries is not to store excess energy because there's nowhere for it to go - it's because solar cells don't produce energy consistently. What if you have a day that's excessively cloudy and/or dark? The batteries store unused energy on good days for use on bad days when there is a defecit of available solar energy.

Second, there are some designs out there that focus solar energy for heating applications, such as the driving of a sterling engine attached to a generator. This, it should be noted, is far more efficient than normal solar panels. There's already a thread on the efficiency though, it's in engineering, IIRC.

Oh, and most states have the same requirement of the power companies - they must pay you for putting energy into the grid. Some people attach solar equipment straight (and only) to the grid, and are paid more for their power than it costs them to buy it back from the power company, especially after their reduced rates. In other words, they are actually earning money from their power company by buying power from them.

You could add a spot to the admin panel to add a custom style sheet link. You could also add a style sheet control to the admin panel.

If I had time, I'd help you. Maybe next weekend. I'd be willing to look for vulnerabilities, but the time it would take for me to find any would be greatly reduced if I had the source code (the PHP I mean). I wouldn't call myself an expert coder or anything, I just like challenges, and know a bit about various important PHP exploits.

[Edit: wait, is that the download link on sourceforge? If it is, let me know - it's late and I can't think... Not that I would have picked up on that normally, but you get the idea. [Edit edit:what do you mean, it doesn't have an installer? Isn't it just some php files and a db file? Does that need an installer?]]

I'm not sure if you all knew this, but I didn't. The knocking or pinging ina car engine is also Detonation ! The unburnt fuel air mixture explodes before the flame front reaches it causing detonation. I read it somewhere on wiki, can't remember where though....

Yeah, i seem to remember hearing about that somewhere, but the term "detonation" is often used very loosely, so I never took it that way before. That's actually rather interesting - it makes sense, too.

Also I have a few doubts about detonation. How can you actually cause it rather than Deflagaration. I'm not sure my understanding on this is right. What factors will affect whether it takes place ? Will largely increasing the compression/pressure create it ? If so, then I have a few ideas that might work !

From my understanding (which is not very good either), it's all about helping the shockwave to propagate. I think the wikipedia article (or a link from it) explained the process in more detail. The shaping of the detonation chamber takes a big role, too.

Note: THIS IS NOT QUANTUM COMPUTING. From every description I have heard, this is an example of chips designed using nanotechnology. Quantum computing is a completely different thing. Check wikipedia for both "quantum computers" and for "atomic-scale computing." The difference is immense.

Yep, that was the idea.

There have been many scholarly journals / respectable science magazines reporting on nano-scale data storage (non volatile). It is, in fact, possible to fit that much data into something that small!

I'm not sure exactly which articles I'm referring to 'cause I don't remember exactly what it was, but IEEE Spectrum, Technology Review (MIT's Magazine of Innovation), Scientific American, and Popular Science are some good candidates.

As far as this particular case goes, I don't know.