The Rijke tube, first described and name after Dr. P.L. Rijke is extremely simple device and yet is a wonderful demonstration of thermoaccoustics,
(sound produced by thermal energy) it was first demonstrated dating back to approx. 1858. The device consists of a tube with a metal screen inserted about 1/4 or 1/5 of the way in from one of the end. The tube is activated by heating the screen with a Bunsen burner or torch sufficiently and when the tube is turned vertically emits a tone that will last up to about one minute.
The frequency is dependent on the temperature of the air inside the tube, measuring it from the start until the tubed cooled enough that sound stopped showed a change of about 3 Hertz.
Suggested length: I found success with various tube length but generally suggest the length should fall somewhere between 8 times to 24 times longer than the interior diameter of the tube, with the most success with a ratio of 14 to 1
no success with tubes smaller than 3/4 inch diameter and any tube less than 1 inch diameter may.not work with 3 screens thickness.
Longest successful tube so far has been a 7 feet long cardboard carpet tube
Tube types/ materials that I tried,
glass works well but must be borosilicate or pyrex suitable for high temperatures. Special care needed with glass and hot glass!
Stainless steel, my favorite tubes, work well, sounds lasts the longest of any of the tubes
aluminum works well
galvanized pipe works
steel vent pipe okay sound seemed to die out quickly
aluminum downspout interesting in that it was the only pipe that where it wa being held was critical, tube itself vibrates
copper, works but not well, conducts heat so quickly it gets hard to hold and does work when the bottom of the tube gets too hot
cardboard works but not as long as metal tubes, must if careful about heating the screen, love the big bass sound emitted by carpet tubes
27 июн 2024
