Friday, November 19, 2010

Super Deicing





This is obviously going to be welcomed everywhere and not just on airplanes.  Car windshields will be high on the list of first adopters.

Somehow it will be while before we need friction free roadways though.

However a couple of comments are possible even there.  First, heavy lift, and that means all trucking will end up been better handled with dirigibles even at the local level.  What I mean is that a balloon can drop a container at a delivery pad from a height of less than a hundred feet and then scoot direct line to the next pickup.

This suggests that the whole trucking industry is today ready to transition to airlift transport.  Costs will start high but quickly drop to levels which make them compete directly with road service.  Shipping will evolve to container bays that are loaded and unloaded in preparation, and timed dispatch by airship using fast grab and drop technology.

Recall that the economics of helicopter logging ultimately caused logs to be pulled every couple of minutes and dropped at the loading site.  Imagine an airship working all day over a city moving containers.

This evolution will hugely reduce the wear and tear on road beds.

Secondly, the one ton vehicle is also getting ready to disappear mostly and to be replaced by an electric vehicle weighing around half as much for a forty percent less impact of roads.  In addition the human driver is also disappearing.  This all means that actual roadbeds can be far more finely engineered. Tires can be settled into slightly recessed track ways with excellent braking characteristics.  The unthinkable can be tried.

Of course, the advent of a shedding skin will allow airships to operate in far worse weather than would be chanced today.  At icing blimp is a really bad idea.



Nanostructured materials to put an end to icy airplanes and roads
21:34 November 15, 2010
Icing on surfaces such as airplane fuselages could become a thing of the past, thanks to newly-developed nanostructured materials


  
Much to the chagrin of those of us in the Northern Hemisphere, winter is once again on its way. For many of us, this means a return to icy roads, sidewalks, power lines and even airplane wings. Traditionally, the main methods of getting rid of this ice – or at least, keeping it under control – involve the use of salt and/or de-icing chemicals. Both of these are labor-intensive, environmentally-unfriendly, plus the salt kills grass and causes cars to rust. Now, however, researchers from Harvard University are developing nanostructured materials that could keep ice from ever forming on surfaces in the first place.

Like the superhydrophobic coating developed by a University of Pittsburgh-led team that mimics the rutted surface of lotus leaves to reduce the surface area to which water can adhere, the Harvard team got their inspiration from natural models. Although the principle is the same, instead of the lotus leaf the Harvard team turned to the eyes of mosquitoes and the legs of water striders for their inspiration. In both cases, the insects are able to keep these body parts dry due to an array of tiny bristles that repel droplets of water by minimizing the available surface area.

The researchers proceeded to create silicon surfaces incorporating various nanoscale shapes, patterns and geometries, such as bristles, blades, honeycombs and bricks. When they watched slow-motion videos of supercooled droplets hitting some of these surfaces, they saw that that the droplets would initially spread out, but then retract back into a sphere and bounce off before they could freeze. The surfaces with interconnected patterns were particularly effective. On regular smooth surfaces, by contrast, the droplets would simply spread out and freeze.




The nanostructured materials were shown to prevent the formation of ice down to a temperature of -30C (-22F). Even below that, what ice did form wasn’t able to adhere well, so would be relatively easy to remove.

“We see this approach as a radical and much needed shift in anti-ice technologies,” said team leader Prof. Joanna Aizenberg. “The concept of friction-free surfaces that deflect supercooled water droplets before ice nucleation can even occur is more than just a theory or a proof-of-principle experiments. We have begun to test this promising technology in real-world settings to provide a comprehensive framework for optimizing these robust ice-free surfaces for a wide range of applications, each of which may have a specific set of performance requirements.”

The research was recently published in the journal ACS Nano.

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