I want to make a portable smoke generator

[andylaurence]

I've seen great airflow lines over my car after driving in the wet and the dirt sticking in the right places. I should've got a picture. It happens every so often. As for the oil in the intake, it takes very little oil to blow out the breather and into the intake before you have huge plumes of white smoke behind you. Ask me how I know

[JasonG]

Model airplaners have found a 50/50 mix of diesel and canovus form release oil makes the best smoke for acrobatic planes. ATF works well but smells odd.
That said, Check your state laws.
In most states even having a smoke generating device, nevermind using it on the road, is illegal. In some you will lose your car and get a heavy fine. The authorities don't want big smoke clouds blocking other drivers vision.

[vtec-e]

I found a picture of an f-18 with aerodynamic test equipment on board. They had a load of nozzles fitted to places they wanted to study and pumped a liquid through them that stained the body, revealing the airflow. Here's a link to the picture:http://www.dfrc.nasa.gov/Gallery/Pho...8-0212-002.jpg
I found it elsewhere in the nasa site with a description but can't find it for now.

ollie

[chuckm]

Check out McMaster Carr's smoke candles and pens. They also have a 120VAC smoke generator, but getting onboard power would be a challenge and it's a bit expensive (~$500).
Grainger has some stuff here as well.

[MetroMPG]

Jack - I recently saw a film crew create A LOT of smoke from a single small source on a moving boat to simulate a foggy day in a harbour on a calm day. Tracking down a movie effects company might lead you in the right direction.

Also, I suspect the film industry is subject to regulations that might mean whatever they're using may be less noxious than simply burning oil/whatever.

[aerohead]

There are commercial smoke generators.SAE published an entire book on imaging,including smoke and it might contain info on fabrication.I've glanced at it but don't own a copy.Texas Tech Aero Lab had a commercially produced smoke unit we used on a model in 1991.$1,100.00 US was the price at that time.A non-toxic oil is electrically heated and flashed off as smoke in a chamber exposed to the windtunnel airflow and flows to the rake,exiting at the exact velocity of the tunnel's flow,so as not to introduce turbulence right at the rake.------------- To do this on a moving car would require some fanagleing,as well as providing a sinewave inverter powerful enough to run the unit.---------------- You might cobble up a DC- powered unit to do the heating and experiment with a ram tube you could calibrate to match to the car's outer flow field.--------------- Demonstration parachute teams and aerobatic airplanes both do smoke.I think the parachutists use smoke bombs.They can be purchased at HVAC suppliers in sizes up to 50,000 cubic feet.The thing about them though,is that once you light them,they burn to conclusion----------------- I think the aerobatic planes spray oil onto the exhaust system.Don't know for sure.-------------- A bunch of us have settled on yarn tufts taped to the car for proof of flow.Darin has a boom which supports a video camera and he's self contained.I end up getting friends to drive "chase" cars and operate the camera to "freeze" the action.

[Cd]

I've thought of this sort of thing in the past as well.
I second what Metro said about trying to find an special effects outlet.
On a much smaller scale ( If the price on the movie set sized one is too steep ) , you could buy a home smoke machine ( smoke generator ) once Halloween is over and they drop the prices.You would really need to pump out a lot of smoke with it though .... and where would you plug it in at ??
I tried one and it didn't put out enough smoke once the fan kicked on in my small DIY wind-tunnel.
Since they are for use around people, they would certainly be more environmentally friendly than the other options given so far.

( MOTHER would thank you )

BTW, How's MAX coming along ? I suddenly got really interested in the car when I saw the aero mods planned. It's cool how that you retained the 'classic' look, yet have a car that is very streamlined. Well done !


( Hmmm... O.K. so maybe the Halloween smoker wouldn't work. Well hmmm... what about a large Thermos of dry ice connected to your wand ??? ... grabbing at straws here.

EDIT : Sorry for posting an idea that was just mentioned. I rushed in without thinking.

[Cd]

One more straw to grab at - A bug fogger ( minus the toxic poisions ). That would be portable and it already comes with ( sort of ) a 'wand'.

[aerohead]

Originally Posted by Cd

One more straw to grab at - A bug fogger ( minus the toxic poisions ). That would be portable and it already comes with ( sort of ) a 'wand'.

Cd,your brain must be as twisted as mine! I grabbed a second-hand CRAFTSMAN bug fogger at a local flea-market for $15.I've made no attempt to fire it up so she languishes amidst my mountain of "treasure." When time allows,I'll research the oil used in windtunnels.Shell makes one I'm pretty sure of,although it's probably a "special" and not locally available.

[Cd]

Originally Posted by vtec-e

I found a picture of an f-18 with aerodynamic test equipment on board. They had a load of nozzles fitted to places they wanted to study and pumped a liquid through them that stained the body, revealing the airflow. Here's a link to the picture:http://www.dfrc.nasa.gov/Gallery/Pho...8-0212-002.jpg
I found it elsewhere in the nasa site with a description but can't find it for now.

ollie

I saw a device that ecomodders were using back in the '70s that consisted of a funnel pointed into the wind. The funnel was then connected to a length of clear tubing filled with colored fluid. As the car got up to speed, the fluid was pushed out of the tube on the area needing to be tested. There is a certain name for the instrument, but I cant think of it now.
It produced the exact same results as those shown in the F-18 image.

The magazine that had this article on ecomodding was published around 1978, and I have long since forgotten the name of it. It was devoted mainly to hot rods - in fact the car that tey were ecomodding was a '69 Camaro.
( Imagine that ! )
They added a large air dam to the front of the car and did coast down testing as well.
P.M. me if anyone recognizes the magazine I am talking about.

Sorry for the hijack - back on topic please ( P.M. me instead please )