backtop


Print 68 comment(s) - last by oTAL.. on Jan 8 at 10:11 AM


Kronos cooling run at 8.5kilo-volts to cool a device 25 degrees Celsius - Image courtesy TheFutureofThings.com
Kronos Advanced Technologies claims that's the way we're headed

Lately, heatsinks and traditional fans have become so large that they are beginning to be obstructive and are sometimes too heavy. This is an issue on the graphics processor front in many ways, as there isn't enough room for large heatsinks, yet GPU thermal exceeds that of high-speed CPUs.

A company called Kronos Advanced Technologies is working on a method of removing heat from devices such as CPUs by using ionic discharge to create a fluid motion of air. This technology has been around for a few years and is used in products such as ionic air filters, which have no moving parts but still move volumes of air and create quite a strong breeze. The same concept is being applied to micro processor cooling.

Despite the advancement however, the volume of air moved over the CPU core is still small because the core surface area is small. Heatsinks are used to increase surface area of the hot surface, so that when air is moved over the fins, more heat can transfer to the air. The Kronos' device will attempt to remove hot air away from the processor core directly without the need for heatsinks. With this method, the velocity of air being moved needs to be extremely fast in order to compensate for the lack of surface area -- and speed is something that ionic air "movers" lack.

Right now, Kronos is still working on prototypes, which it claims are scalable from very small micro coolers to large scale sizes. Power requirements also appear to be quite steep at this point in time. One of Kronos' demonstration shows a heated area being reduced from roughly 50C to 25C using an ionic cooler, but the power supply required around 8.5kV, or 8500 volts, to stay stable.


Comments     Threshold


This article is over a month old, voting and posting comments is disabled

RE: 2.5kV?
By masher2 (blog) on 1/4/2007 11:55:43 PM , Rating: 5
> "Let's say you touch 100kV and we assume a body resistance of 1000 Ohm...we will see a current of 100mA flowing through your body (I=U/R)...It is, however, not an issue if you're properly insulated from ground potential - and that is most likely what you were "

No, you're incorrectly using Ohm's Law. In simple terms, you must realize that real-world voltages are not idealized sources, and do not remain constant regardless of load. Even in the case of 120VAC house current-- once current begins flowing, the potential drops. Voltage is measured assumming infinite resistance (or, if you prefer, zero amperage).

In the case I described, I most certainly was touching a >100kV voltage source while well-grounded, and thus current was flowing through me. A few microamps at most...which explains why I'm here typing. The reason your calculation of current was incorrect is, because the moment I touched that source, the current flow caused a corresponding potential decrease.

> "Also, ventricular fibrillation is not only a result of current flowing through your heart. Frequency is also a important factor..."

Certainly; I never said otherwise. However the fact remains that amperage is the primary factor in inducing fibrillation. Voltage is irrelevant, insofar as enough exists to overcome body resistance.


RE: 2.5kV?
By Griswold on 1/5/2007 3:45:57 AM , Rating: 1
quote:
No, you're incorrectly using Ohm's Law. In simple terms, you must realize that real-world voltages are not idealized sources, and do not remain constant regardless of load. Even in the case of 120VAC house current-- once current begins flowing, the potential drops. Voltage is measured assumming infinite resistance (or, if you prefer, zero amperage).


Now you make me smile. You are of course partly correct, but the potential drop is not nearly as big as you make it sound. Please, remain with me in reality. Ohms law is perfectly clear. The example is perfectly valid. The fact it may not occur due to technical limitations/safeguard of the voltage source does not change that.

quote:
In the case I described, I most certainly was touching a >100kV voltage source while well-grounded, and thus current was flowing through me. A few microamps at most...which explains why I'm here typing. The reason your calculation of current was incorrect is, because the moment I touched that source, the current flow caused a corresponding potential decrease.


Dont forget to mention what kind of voltage source it was. In your case, it was, most likely, a van-de-graaf generator, which generates DC (with indeed extremely low currents due to the static nature of the voltage) and thus you would not need to be insulated from ground potential. Try that with a tesla generator and report back, if you can.

quote:
Certainly; I never said otherwise. However the fact remains that amperage is the primary factor in inducing fibrillation. Voltage is irrelevant, insofar as enough exists to overcome body resistance.


Again vague and incomplete. Current is a result of voltage in your body. DC will not to the same as AC either.



RE: 2.5kV?
By masher2 (blog) on 1/5/2007 6:41:48 AM , Rating: 3
> "Now you make me smile..."

Always happy to provide a little joy in people's lives.

> "Ohms law is perfectly clear..."

It's always been so to me. The fact remains you're applying it incorrectly, by assuming idealized voltage sources. Connect a 1000 ohm resistor across a 9V battery, and you can treat that battery as an idealized source. Connect a 0.1 ohm piece of wire across the terminals, and you cannot. Many high voltage sources supply very little current, and thus to measure their voltage potential at infinity, then apply Ohm's Law using that voltage against a low resistance, gives incorrect results.

This is really pretty basic electrodynamics. And it explains why some high voltage sources, such as a static sparks, Van der Graaf generators, and the ionic generator in this article-- are all non-fatal to touch.





"I mean, if you wanna break down someone's door, why don't you start with AT&T, for God sakes? They make your amazing phone unusable as a phone!" -- Jon Stewart on Apple and the iPhone

Related Articles













botimage
Copyright 2014 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki