/diy/ - Do It Yourself

>>1541213
I mentioned it in >>1541133 but I'd like to avoid it if possible because the thing will easily get clogged with grease, or at the very least be a pain to clean. The problem with using a small hole is that the pressure builds up and causes the edges of the lid to start leaking significantly. 1cm is probably borderline for that, since the ~3mm holes definitely seem to have that issue. But it's also important to be able to measure very low levels of boiling, like a 1/10 or less on an electric stove.

I threw together a spreadsheet for a variable area flow meter with calculations that simply balance the gravity force of the ball with the drag force of the air going past it, pic related is a reasonable configuration. "h" is the height that the ball moves up the tube due to the influence of the flowing steam, the angle is the angle to horizontal of each side of the tube, "D" is diameter, "C drag" is the coefficient of drag, and "v" is the gas speed. Note that since the gravity force is constant, the drag force must also be constant, and so as the area of the meter changes the speed remains constant. 0.8mm minimum is a bit shit though, so I may replace the conical shape with a curved air-horn shape to get higher resolution at lower levels. Here the maximum height is 11cm, which sounds reasonable. I may or may not be designing a massive steam whistle.