Tri-phase Hydrogen water cannon

[hydroblast]

I was'nt aware of the smooth bore approach,(teflon). I think the real trick is trying to make it portable. The valve and pressure pump take a lot of juice(electricity).
Anyway, I was trying to create a water machine gun with an illuminated water stream.
Thanks for your help.

[Ben]

I don't think friction is quite that big of a deal to coat the internals in teflon. I remember a discussion about this on a long-gone message board (WaterWar.net back a few years ago). To summarize, the easiest way to reduce friction would be to increase the internal diameter to decrease the total percent of water touching the edges, which has other benefits as well (mainly flow). Teflon would increase performance, but I don't think it would increase it very much if noticably.

[Silence]

Hmm...Ben does have a point. You're going to have a velocity gradient with no velocity on the surface, no matter what the surface is. Teflon can help reduce turbulence, but it won't change the velocity gradient.

It would be a very neat experiment to test exactly how effective Teflon would be as opposed to surfaces like those of PVC and copper.

[Kalogagatya]

yes i agree that the effect of teflon isn't much on small diameter flows. however, in this case the ideia is to have a high velocity flow on a considerable diameter condition.. friction is not affected by area, but diameter does affect friction.

this is a complicated matter but i'll try to make it simple

about friction -> this friction is NOT the same value in classical mechanics Friction=coefficient*weight (in a simple way..):

if a flow is laminar (small velocity, small diameter, high viscosity) then friction will in most cases be very small, depending only on these values.

in water guns we have a big velocity, relatively small diameter and VERY low viscosity (from all the liquids, only amonia has less viscosity than water....)
and so our flow is either almost turbulent (kind of a heart beat, not all the flow is turbulent), or it's fully turbulent.

in this case friction depends on rugosity (and this is where teflon has its importance), diameter and Reynolds number (velocity*diameter/dynamic viscosity).

in detail (Colebrook equation):

1/sqr.root(f)=-2*log[(rugosity/diameter)/3.7 + 2.51/(Reynolds*sqr.root(f))]

...
there is no simple way to solve this :P

and then in the Bernoulli equation, power loss caused by friction (hf):

hf=(f*L*V^2)/(2*g*D) g=9.8 m/s^2 (sorry, SI units :x)

what happens is that altough velocity remains the same, you will need MORE pressure to reach that velocity. on the other hand, if you have that pressure and eliminate friction, you will get more velocity..

considering that you use a watergun horizontaly (gravity effects are not considered that is...) and the velocity remains the same (which would happen in a simple configuration such as the one hydroblast described), in a simple way:

p1/(density*g)+v1^2/(2*g)=p2/(density*g)+v2^2/(2*g)+hf+hl

p1 - pressure in the air tank
p2 - exterior pressure (14.69 PSI)

which develops into:

(p1-p2)/(density*g)=hf + hl

hl represents localized power losses (such as intersections, valves, etc etc..)

and this is the way friction affects flow. p1-p2 represents the differential you need to aply for the required velocity.. you need to use a iteractive calculus method for these equations though .. :| you can also use a Moody chart/diagram to help you out..

bottom line: because in most cases we're talking about devices that don't need that much care for details such as rugosity and friction, it may not be very important but i'm sorry i like to show you all that's going on in these situations =) for example, i have a fluid dynamics exam: "find the power loss value on a typical turbine intake assembly.".. i couldn't answer "who cares?.." hehe

[Silence]

Wow, this is some high-level information! Too bad the forums won't let us easily see symbols like rho.

In those equations, what does g signify? Mass (in grams)? Also, do you think we could come up with a rough estimate of hf if we knew the material's surface area and rugosity?

I suppose parts of those equations can be replaced with a constant k, since variables like density don't change - at least not for water in water guns.

Yeah, it's nice how we don't need very precise calculations. Once again, thanks for all your help!

[Kalogagatya]

g is the acceleration due to gravity..

yeah you could that. there is actually a constant (greek symbol gamma) for density*g

i think you could do that.. but first try some home built simple water guns to check if affects the power that much..

no problem!

[hydroblast]

I asked originally about creating a sharp on/off pulse from a portable water gun. A rotating tubular disc may give me the pulses I'm looking for, however I don't have a complete understanding of how to best dispense the water stream. I've seen many hose adaptors that have a long taper before the actual nozzle,( fire-hose-ish). Is this long taper best for water gun nozzels?
I know that water stream dispersal is a factor if you simply drill a hole in a end cap for stream size,(and spray).
Any common sense thoughts would be appreciated before I start spending money on parts.
Thanks Hydroblast

[Ben]

Too bad the forums won't let us easily see symbols like rho.

I believe there is a forum modification that lets you use many symbols. I'll have to investigate it.

Is this long taper best for water gun nozzles?

Yes. The long taper reduces flow loss and also reduces turbulence created in the nozzle. It basically comes down to the basic principle of avoiding turns and such in water guns. Flat endcaps have a more complicated path for the water to follow, which creates turbulence and reduces flow. These "smoother" conical nozzles however have a straighter path.

There are other good things to have in a nozzle too. I believe there is a thread here about water nozzle patents, but I'd have to dig it up. The easiest and best thing to do would be to have a conical nozzle still, but other things can help reduce turbulence further.

@Kalogagatya: Feel free to post these explanations. They're appreciated very much. I am unfamiliar with the equations you're using (I just graduated high school and only have basic Calculus knowledge), but I can see where you're going with them. I think you know what I'm talking about though... friction's effect exists, but for the most part is negligible unless we're talking super-high flow water guns (wait... that's actually what I want to talk about sometimes!).

[hydroblast]

I think I understand now. A long same diameter tube invites fricton, a tapered nozzle keeps the fricton away yet delivers a stable consise water stream. Add a little teflon, and wow!
I think I'll try shaping 3/8" sink supply tubing.
Thanks guys!

[powerpit25]

I saw a news broadcast the other day. Some guy trying to invent a way to cure cancer, stumble on a way to break water molecules in to constituent atoms (two hydrogen and one oxygen), from ordinary salt water -by bombarding a 1" test tube full of salt water with radio waves! By the looks of it, microwave energy(don't quote me), not enough to hurt his hand place in front of the waveguide aperture, but enough to produce enough gases that when ignited with a torch flint striker, produced and sustained a 8" flame at a temperature of more than 1200 degrees f! Some Energy management type scientists observing this were creaming their jeans about it 'cause it looks like it is the breakthrough of the century we need to run cars on water and generate excessive amounts of electricity using just water and a little salt....whala!

I am officially impressed...just what you need to power your water gun eh?

Search the net for the link to the broadcast clip.

If I find it, I will post it here for your viewing pleasure.

By the way. The inventor IS willing to sell all the specs and plans. Obviously, he did not disclose any of the pArcticulars. but it looked simple enough to me, through trial and error, I should be able the figure out the frequency and wattage since THAT is the only secret to this! Anyway for now.

Edit:

Like I promised, here is the link to the Arcticle.

Watch the video, then pick your jaw up off the floor


http://search.wkyc.com/sp?aff=101&keywords=hydrogen

Then click on "water into fuel" headline

[hydroblast]

Thank you, Thank you, Thank you!
Yes that was an amazing clip. I have an extensive back ground in technology and all I need to know is the frequency. This is alot like the flame vortex I'm working on using high voltage on frequency as the carrier for the spiral flame extension.
I really want to know the frequency, obviously thats the key. From what I saw it looks like he's bombarding the entire tube. My guess would be the signal is tuned to either the space between the molecules or the molecules themselves,( Or an outside chance that its a sub-harmonic frequency of the above mentioned molecules).
Once more, thank you, I will check that out!!!

Hydroblast

[powerpit25]

Don't blow your self up!

My opinion is it is definitely low power and due to wave guide size, frequency isn't that high..maybe, for show, he is resonating the VOLUME of liquid....

just a thought....jjuuuust a thought

Also Impedance, loading the 'Q'..thinking more about it, probably more complex than just frequency alone...modulated harmonics,am-fm, stereo, surround-sound
with or without dolby ahhh who knows..I must figure it out, so I can take over the world..booah ha.ha.ha

[Ben]

Welcome to Super Soaker Central powerpit25!

I saw this before and I think the jury is still out on it. For those who don't know anything about energy, creating a powerful enough radio wave may take more energy than is released from the salt water. I think the fact that he didn't provide any energy requirements indicates that it uses more energy than it produces... but we'll see.

hydroblast, I believe his patent application will provide some of the information you are looking for: http://www.freepatentsonline.com/20060190063.html

I have not read the entire thing in detail, but it does mention a few frequencies from what I can gather.

[powerpit25]

As I scanned that link, I found ONLY the medical application of the patent you referenced. Nothing about the fuel generation. The patent search site IS amazing though, I could spend hours getting inspiration from it...so I'll bookmark that for another time.

I did stumble onto this though.....check it out. It made me chuckle!

What is your opinion?



http://www.wam-a-bam.com/hydrockickb...1&tid=S9372NSH

[Monsoon]

Also be careful since microwaves and radio waves are two different types of waves as well (wavelengths makes a difference--you can't cook with radio waves )