A new way to remove ice buildup without power or chemicals | Hacker News Reader

A new way to remove ice buildup without power or chemicals

phys.org

62 pointsdnetesn18 comments

Not directly related to ice, but...

A fellow lives near a new wind farm, and a TV transmitter. Both the windmills and the TV tower are in direct view. He, and I assume also others on that area, have had great trouble receiving a good picture. Even the technicians from the broadcasting company are scratching their heads. 100m rotating blades create awful changing reflections.

It would help if the blades were coated by some absorbent material. Just the sharp edges, if the material is too costly.

The defence forces have even banned wind farms from certain areas, I read on the papers last week. Too much interference on radar.

I don't know what the current situation is with fellows TV reception. I assume careful aiming of TV antenna has helped.

There are a few companies that specializes in removing that noise from radar systems used in planes. Apparently it isn't easy.

You might try and look for a ground wave vhf antenna and see if you can pick up something from the TV station. 100m is very close

The top layer is an absorber, which traps incoming sunlight and converts it to heat. The material the team used is highly efficient, absorbing 95 percent of the incident sunlight, and losing only 3 percent to re-radiation

Is there anything to prevent the surface from getting too hot? Solar is powerful, but as anyone who knows of the dangers of fresnel lenses and magnifying glasses can tell you, it can sometimes be too powerful.

The good news is that the heat isn't concentrated on a single spot, it's spread out quickly over the surface. In contrast, a lens concentrates the light to a small spot. It's the localized heating that causes things to catch fire.

And the heating isn't a one way street. It's either converted to the melting of the ice, or re-radiated at longer wavelengths.

There are issues with solar loading on aircraft fuel tanks, which are essentially the inner volume of an airliner wing. The induced gas flow in a tank can result in hotspots as heat pools in the internal structure.

That layer of insulation seems like a double-edged sword. It would keep incoming heat from being wasted on the interior, but without it, the internal heat of the object can keep the surface from freezing as quickly.

So, for example, if an object is moved entirely into the shade for 10 minutes, perhaps in certain cases without the insulation it would not freeze but with the insulation it would.

Also, it might be harder to use an internal heating element for the cases (like night time) where the solar approach isn't good enough.

This is pretty cool, I wonder if this could be used on roofs in places where ice dams [0] are a big problem.

An alternative and cheaper system which my team and I developed in our undergrad senior capstone was to use drip irrigation mounted to roofs (and organic deicing fluid) to mitigate ice dams. This was accomplished by dripping fluid down the roof to "cut" channels into the ice dam to allow the water built up behind the dam, to drain off of the roof. I think you could possibly do something similar by placing strips of this 3-layered material vertically oriented on a roof to melt channels in the ice dam..

[0] https://en.wikipedia.org/wiki/Ice_dam_(roof)

At power output produced by APU of a large airliner, electric deicing looks to be almost free.

For smaller planes, things are different. Pneumatics is an acceptable compromise, and piezoelectric that is soon to come to the market will have almost no flaws besides the upfront cost.

From a thermodynamic perspective, roughly speaking fuel based engines convert the flow of heat from a high temperature heat bath to a low temperature heat bath into work. The higher the difference between the temperatures the more work can be extracted. It would seem to me that in theory the vehicle surface area could be used as the colder heat bath for improved efficiency.

I am not claiming any actionable specific device or configuration design to improve the efficiency though!

Would this work to deice heat pumps in winter? There are obviously some factors working against it (low temperature, shorter days), but maybe with enough surface area?

Would these layers be thin enough to be translucent?

My thought is that in order to be thick enough to absorb sufficient sunlight, they also have to be thick enough to look black.

Not so useful if your airliner flies at night as well

Or above 50degrees latitudes

That's actually incredibly useful. The aviation industry and any pilots must be stoked.

This probably wont work well if all in cloudy days or with any kind of snowfall (due to very low amounts of incoming irradiance). Also, just the aluminum coating in this 3 layer material weighs 586 kg for a 747 wing area.

Wow, that does seem like a huge amount. On the other hand, 184,567 kg is the empty weight so it's "only" a 0.3% increase. Maybe not so bad since they don't need to carry deicer anymore?

They dont carty deicer anyway...they use bleed air from the engines.

Reply on news.ycombinator.com