Category Archives: homebuilt

Air Wasp

Not to be out done (by complaints or police) I’ve found something to keep my self active, have you ever heard of a “Hilsch Vortex Tube?”, nor had I, till just recently. (once again thanks to Mark and Stumbleapon!)

Put simply it divides a stream of gas (or liquid) into a cold and hot flows.

Commercially available ones claim to get down as low as 20 degrees C above absolute Zero!

I also read a blog that a hobbyist claimed to get 275 degrees F on his “hot”side! (point 1. I don’t believe it, point 2. I can’t find the blog in question to make sure I read it right, (I’m sort of Dyslexic) point 3. if I’m wrong about point 1. and point 2. I apologize and Kudos to you for doing it at home, well done! (Card carrying Engineers eat your fucking hearts out!))

Here is one I prepared earlier!

As you can see it is made from standard, over the counter plumbing parts, the “Hot” end is the bit with the Blue handle, (actually it’s a 3/4″ Ball Valve!) the silver bit near the top is a Hi Flow Compressed Air fitting (male) and, of course the short piece at the top is the “Cold” end!

Now lets take a look inside shall we?

Basically, as you can see, the air is made to swirl as it enters the chamber (aided by the offset input, the aluminum piece inside and even the thread of the collar that makes up the outside of the chamber!) Note the washer (reducer) to the left of centre, this is very important as the air must travel to the hot end first forming a vortex then the hot air passes thru the ball valve whilst the cold air compresses into a smaller vortex which moves back down the low pressure area created by the original vortex and passes thru the reducer into the cold end

The ball valve seems to have more effect on the cold than the hot!

When tested (with a multimeter and a temperature probe) the best we got out of it
was8 degrees C at the cold end and 24 degrees C at the hot end!
The ambient temperature was about 14 degrees C!

Not too shabby, for something that took me more time to shop for than it took me to build!

I’m sure I can improve on those specs by making the swirl chamber more precise!

Remember that there is no such thing as cold!
It is merely an absence of heat!

Cheers all for now, Mick. ;-))