The non scientific part.......
I used a stainless teapot (bad choice as it let heat escape through the spout and I guess SS is harder to heat than Aluminium)
Temperature was around freezing but there was no breeze.
The Build.......
I used what was to hand, a coffee tin, a cat food tin and a tuna tin. The coffee tin had a pop-off plastic lid but when it was open there was a lip/edge on the inside which was a more or less tight fit on the cat food tin. I did have to roll the lip back a bit to let the cat food tin fit. The reason I used a cat food tin was that it had a rounded base rather than one with a lip which meant I could press it into the outer (coffee) tin more easily. The Pot stand was made from a tuna tin which when cut sat nicely on the lip of the outer tin but could be stored by sliding it into the base.
I started by cutting the base from the outer tin and making some air slots around the bottom, I then made two rows of holes in the inner (cat food) tin, one row about 10mm from the top, another the same distance bottom, the holes were about 10mm dia. I then punched as many holes in the base of the inner can as possible. To make the windshield/pot stand I cut a section from the tuna tin, removed the base and made a few vent holes (it might have been easier to use a tin like pineapple rings come in as most have a base that can be opened with a tin opener)
The End Result.......
Really rough build but it's ah .................... um................
....... a work in progress :-)
The base with a load of holes!! The inner after finishing boiling the water
The windshield ready to store. Packed to go, knife shown for scale.