Well here is the complete guide on how to make a cheap and efficient wind tunnel for projects etc.,
What you will need:-
- A Pringles container
- A medium sized cardboard box
- Some straws
- A computer fan
- An LED bulb
- Two AAA batteries
- A switch (optional)
- OHP sheet
- An ac to dc adaptor(according to specs of fan)
- A small plastic box or battery holder
Step 1: MAKING THE PEEP HOLE
Cut a clean flap on the Pringles canister to sufficiently see your test subject.
Then cut the flaps interior according to the image.
Then cut the OMR sheet according to the dimension of the peephole.
stick the omr sheet on the flap frame.
Make hinges for the flap to be opened and closed.
Do not make the peephole to close to the ends of the canister or the flow straightener will cover it.
Step 2: MAKING THE INTAKE
Firstly cut off the metal bottom of the canister cleanly.
The intake is made from a cardboard box with one side open for the fan and the other the test section.
You must narrow down the other side to the width of the canister.
then place the CPU fan in the larger end.(there must be no gaps between the cardboard and fan).
Step 3: Making the Flow Straightner
First bundle up the straws,then cut them having a length of 5 cm.
Bundle them up so that they fit the canister mouth snugly.
then put them in the mouth of the canister.
Step 4: Connecting the Intake to the Test Section
Now tape the cardboard inlet you made with the other end of canister.
Then connect the CPU fan to the adapter or Battery.(with switch-optional).
Step 5: Making the Lighting
Now make a hole big enough for the LED bulb to fit perfectly.
Connect the LED to the dual AAA battery setup and also connect a switch too.
If you do not have a battery holder you can make a close enough one with paper clips and tape (that's how i did it).
Step 6: Finalizing....
To keep the wind tunnel steady you can also make cardboard stands and also place a toothpick or stick to keep the test subject. Like the one above.
You have finally completed the wind tunnel.
For the sake of testing I used a bunch of incense sticks.(the stream was a bit thin)
but there are multiple other indicators also.