Opaque Water
 

Does anyone know how to make water block an infra-red light source?

Maybe add some sort of red dye? Would a sufficiently high percentage of anti-freeze do it?

All waterblocks are already sources of infrared: you just can't see it.

If you're referring to RED UV dye, that's a whole different ballgame.:dome:

:)

Nooooo.... I want the water itself to block infra-red light.

:)

What bandwidth of IR, what range of absorbtivity, and for God's sake, why? ;)

Alchemy

I may have to switch to visible light - it's not the preferred method, but it would result in a lot less in terms of electronics.

I don't know what spectrum of IR I'm after, but the one that generates the least amount of heat is preferred. How many spectrums are there? :)

Either way, I still need water that light is either diffused in, or where light is almost completely blocked.

Maybe food coloring?

Just make sure You don´t have any IR-sensitive EPROMs on Your MTB.
regards
Mikael S.

But "a lot less" what?

The entire range of IR, from near IR to far IR, goes from a wavelength of 1 micron to 1 mm. Roughly, about 400 THz to 300 GHz.

Not sure if that helps you, since I have no idea what you're intending to do.

That has everything to do with how intense the incoming IR that you want to block is.

All organic materials will absorb a great deal of energy at a few narrow bandwidths of IR, which works great for organic spectroscopy. Not so great for absorbing a wide range of the IR spectrum. Nor can I conceive of any reason for someone to want a fluid to absorb energy from an IR source completely, or any means in which that can be done.

Alchemy

I think you had better explain your purpose more clearly here, before you get turkey-monkey'ed out of these forums!

The only conceivable reason you would want to do this, is to reduce heat absorbed through radiation, which is so minimal that it wouldn't be worth the effort: you'd do far better by increasing your rad-fan's rpm by 1 or 2... (Yes, 1'000 rpm + 1 rpm)

Opaque things *absorb* light. To minimize absorption, you'd want something reflective or transparent.

And yeah, we're talking an absurdly small amount of energy. A crapload more than the energy absorbed by light, but nothing that would increase water temperature by so much as a thousandth of a degree.

JSimmons, really, what is your intention?

Alchemy

I think you may achieve your goal by wrapping your tubes with aluminium foil, but again, it's a turkey-monkey idea, up there with alien mind probes ;)

Re: Opaque Water
 

Geez, I must have completely misread this. For some reason, I missed the word "block."

The waterblock is already an infrared source of light. Just a very, very poor one - it's not at a high enough temperature to emit much IR radiation. Also, aluminum and copper don't have anywhere near the emissivity of tungsten, steel, or compounds like that.

The only way to make a waterblock, regardless of what it's made of, emit a significant amount of IR radiation - that is, enough that you could feel it by holding your hand above it* - is by operating your CPU at a temperature into the hundreds or thousands of degrees.

Fry: "Fahrenheit or Celsius?"
Old Man: "First one, then th' other."

/Futurama joke that amuses me far too much.

Alchemy

*If the block is very warm, you could probably feel heat coming from it via convection through the air. Your senses aren't good enough to feel radiation from anything that cold, and even if they were, they'd be drowned out by the heat coming off via convection.

That would work great (read: "do nothing useful") until a piece of aluminum-clad tubing touched a PCB board and destroyed the computer.

If you're going to do that, you might as well make a tinfoil hat to protect your thoughts and precious body fluids. Purity of essence, and all that.

Alchemy

Hey, ground it and maybe you will think faster!

I'm trying to build a water level sensor for lucite reservoirs. I have yet to see anything already available, so I thought I'd try to come up with something myself. So here goes:

My idea is to have (three or more, depending on desired granularity) IR receiver/emitter pairs aligned along the vertical axis of a reasonably tall reservoir. These IR pairs would each be responsible for altering the state of an associated status indicator depending on the water being low enough to trigger an electronic signal.

There are several concerns:

1) Is lucite transparent to IR? Don't laugh - some glass isn't, so I don't want to just assume that lucite is.

2) How much heat would be associated with three or more emitters (IR LED's) being on 24/7 (or at least while the computer itself is on)? Negligible amounts?

3) If the water cannot be made to block/diffuse IR light, I would have to consider visible light. This has it's own problems:

A) Ricers (my term for people that put lights in their case for no reason except that "it's pretty"), would not be able to make use of such a kit. The same goes for people with windows in their cases.

B) Lucite has an annoying (in this case) tendancy to edge light when a light source is place in close proximity.

C) Photocells are not exactly reliable as far as their light sensitivy values are concerned, so even in a dark case, one light illuminating the lucite AND the water could errantly activate an receiver that is not associated with the emitter in question.

Since the visible light concerns are enough to convince me to try IR first, the IR's spectrum needs to be able to exist in a dark case, a case with just a clear window, a case with enough lights in it to illuminate a small city, and a case that contains a black light.

However, before any of this can work, I need to make sure I can create a fluid environment that can effectively block/diffuse IR light.

Assumtion:

Most/all lucite reservoirs are sealed and the typical modder wants to just tape/screw/glue something on and see the resulting pretty indicator lights.

Status display:

There's a number of different indicator styles that could be used:
- Multiple single LEDS
- a bank of LED's (I've seen them arrange in straight and arched row packages)
- a LED character display
- a LCD character/graphics display
- a VFD

I don't know about IR LEDs, but normal LEDs hardly produce heat at all...

I think you ought to consider a mechanical solution first: it's much more reliable. A simple float mounted to a switch will do. Many such products available.

Otherwise, you might do well with a vertical row of copper electrodes, where a small current will pass if the copper pins are under water.

Easy, mechanically.

Wow, that was not what I was expecting from this conversation. I mean Gawd: that's like developing quantum physics to try to estimate how long to microwave your pizza ... a bit overkill.

A float valve would work great. On the pivot arm, use two brushes that will contact a plate connected to the arm. When the water level gets too low the plate will be removed breaking the circuit and you could do damn near anything from there. Use it to kill your entire PC. Use it to sound an air raid siren. The possibilities are endless.

It's Turkey-Monkey's day today...:rolleyes:

I think I've decided on a different route - the copper diode approach.

Here goes my BillA impression:

:rolleyes:

We are apparently graced by the reincarnation of Rube Goldberg.

Lucite is not glass. And most polymers are transparent to IR, though they can easily be treated to be otherwise.

Maybe 3 watts apiece. And if you're using IR LEDs, you will be emitting IR just beyond the range of visible light. So the answer to question 1 would be yes - if it's transparent to red light, it'll be transparent to near, near-infrared light.

If it diffused the IR beam, it would hit all of the sensors. Same thing if it did any other sort of light scattering. You want the beam to be absorbed.

It would also work poorly if there was an LED on the mobo or the case was not sealed completely.

"Edge"?

Photocells are designed for detecting visible light. IR is at the very edge of their detection. I see no reason to say they have decreased sensitivity in the visible range.

A photocell *will* detect visible light shining on it, and make no differentiation between it and IR. If the lights in the case are anywhere near as intense as the detection limit of the photocell, the sensor will give a signal.

If it blocks visible light, it'll probably block the sort of IR frequencies you'll be making with a LED. So just fill your water with enough dye to make it dark as night and you're all set.

Bit ahead of ourselves, aren't we?

Alchemy

You're talking about copper pins, right?

'cause if you want copper diodes...click me!

Yah - the pins... :)

I have also located a schematic for a four-probe sensor.

I'm off to the electronics store tomorrow.

WTF? Lucite resivores? Can't you get that in clear? And if so why would you need a level sensor if you can see the water level. :confused: :shrug:

I think that the turkey-monkey is unable to bend over, to look down at the res level ;) so he needs an alert/sensor.

Ahh I see. So he will never look at the inside of the computer for the next 6-20 months after he filled the res? because unless a leak pops up, there is not much reason to worry about the water level in a sealed system. Will take some serious time for the water to evaporate. Only use I could see is if a leak formed while one wasn't around and you had the sensor rigged to shut off the pump and computer. But there are much easier ways to do that than a level sensor.

Just maybe there is a reason why no one has started selling level sensors? :eek: ;)