Thermally Induced Acoustic Oscillations in a Pipe : 2nd Report : Oscillations Induced by Interference of Heat Sources

抄録

Thermally induced acoustic oscillations in a pipe in which two or more heat sources are closely installed have been studied analytically and experimentally. The analytical model used in the first report has been improved to describe the effect of the air current temperature change due to the variation of heat flow rate from the upstream source upon that from the downstream source. If there is a certain phase relation between the pressure variation and the heating rate, thermal energy is converted to acoustic energy, therefore an oscillation is induced. The condition in which the oscillation grows has been clarified as a function of heat generation rate, stream velocity, distance between the heat sources and so forth, which is different from that in case of a single heat source. Experimental results using nichrome heaters agree well with the calculations.