building a smoke generator for aero testing.

[aerohead]

Originally Posted by justme1969

Mixture seems to be as importent as the vortexgenerator after burn chamber.
very touchey in all areas and best result was sub standard. worst result wouldnt stay lighted long enough for air pressure to keep it lit.
I had a few streaming spark runs the last attempt but nothing good enough to feel like posting it here unless others are trying also then Ill give some failed spec's to designs tried.
I wish I could use those old black worms that ya light and they grow and that may be an answer in its own way if re purposed with other additives.

Long ago I ran across an article about building a generator.The oil was suspended within a metal wool matrix,inside a chamber common to the airstream.A Variac (model train speed control sort of device) was used to vary the current to the metal wool to control smoke generation.Air from the wind tunnel test section entered the chamber,picked up smoke,and carried it into the smoke wand,discharging at the tunnel air velocity so as not to induce a jet.
Nichrome wire mesh from old,unused flash bulbs (if you could find any)would also be okay as long as you could limit DC voltage and current.
Also,there are AC voltage controllers used for widespread commercial electric furnaces and heating units.

[Xist]

Originally Posted by aerohead

Nichrome wire mesh from old,unused flash bulbs (if you could find any)would also be okay as long as you could limit DC voltage and current.

I have several thousand feet of nichrome wire. If you PM me your address, I will send you however much you want.

I planned on building something called a foam factory, but that is on hold indefinitely. Nichrome wire is so thin and light that one postage stamp should ship enough for most projects.

[doviatt]

Aren't Estes rocket engine ignitors nichrome wire?
Available at your local hobby store....

[freebeard]

The last time I saw the subject come up, in 2012, aerohead was reminicing about smoke grenades at China Beach.

I still have the Lionel model train transformer my parents used with Nichrome wire, those work on 110AC. It might take heavy gauge wires to carry 12DC to the Nichrome.

[Xist]

Originally Posted by freebeard

The last time I saw the subject come up, in 2012, aerohead was reminicing about smoke grenades at China Beach.

I still have the Lionel model train transformer my parents used with Nichrome wire, those work on 110AC. It might take heavy gauge wires to carry 12DC to the Nichrome.

I remember that.

I bought a car battery trickle charger, which is supposed to do the job, but it did not do anything when I tried.

[freebeard]

You remember the folks! They were Makers before the time.

They had a light gauge wire in a jigsaw arrangement, maybe 3-4" long. As I recall, the throttle was set to about 30%. You'd probably need to short right across the generator/alternator.

But what I came back to say is: Bubbles!

They can be generated at ambient temperature and I think they can be tuned for persistence. A multiple exposure of 1 bubble/second would be a low-resolution sampled average, or you could track single bubbles with a high frame rate—60 frames /second would be every 1 1/2 feet at 88fps/60mph.

Foam streamers. The mind boggles.

[doviatt]

I'd personally would feel kind of silly driving around a big bubble machine....unless it was in a parade or something....but that is just me.
Truth is, that is a great idea and it would work.
On the other hand tufts seem silly but, some people might understand what you are trying to accomplish.

[Xist]

Originally Posted by doviatt

I'd personally would feel kind of silly driving around a big bubble machine....unless it was in a parade or something....but that is just me.
Truth is, that is a great idea and it would work.
On the other hand tufts seem silly but, some people might understand what you are trying to accomplish.

I would have been completely confused until I joined this forum. I am confused regularly by this forum!

[aerohead]

Originally Posted by freebeard

You remember the folks! They were Makers before the time.

They had a light gauge wire in a jigsaw arrangement, maybe 3-4" long. As I recall, the throttle was set to about 30%. You'd probably need to short right across the generator/alternator.

But what I came back to say is: Bubbles!

They can be generated at ambient temperature and I think they can be tuned for persistence. A multiple exposure of 1 bubble/second would be a low-resolution sampled average, or you could track single bubbles with a high frame rate—60 frames /second would be every 1 1/2 feet at 88fps/60mph.

Foam streamers. The mind boggles.

Didn't Mercedes do some studies with bubbles filled with hydrogen,to get really low inertia and neutral buoyancy?

[aerohead]

If you just wanted to see your wake,fireplace ashes make an extremely fine airborne dipersant.I made 'play' landmine explosions with them as a young warrior,and they rival Hollywood's best effects.
Sprinkled on a dirt road,a photo-strobe can freeze a wake's image on film or digital camera as a car passes over after dark,vacuuming these minute particles up into the low pressure turbulence.
Caliche roads will do the same if you have access.
Also,if the car has been recently washed,the fine particles will leave an ashen- white patina of dust which will clearly reveal your car's separation line.
Neighbors will NOT understand and will likely be on their smart phone to the Sheriff's Department.
There are also edible powders which make a fine dust.They won't be any better understood.
Friends and family with private property 'acreage' make handy co-conspirators.