円管内高速旋回流の流れ特性

抄録

A swirling flow has a high diffusibility and the high mixed efficiency, so it is used in a combustor, a boiler, a gas turbine and so on. The swirling flow is known that it has various unsteady, and in the case of unstable condition, the swirling flow causes fluid oscillation and it causes a vibration and a noise for fluid machinery. However, there is few reports of the research which is taken account of the high-speed swirling flow, that is, about compressibility flow. In this research, the unsteady behavior of the high-speed swirling flow was experimentally investigated. The high-speed swirl flow was generated by the inlet guide vane and the suction type wind tunnel. The various type of the unsteady flows was found in the large guide vane angles and the lower tank pressures. For 60 and 70 degrees of the inlet guide vane, the peaks near 2000Hz and 5000Hz observed in the large guide vane angles disappeared and the peak near the 3000Hz appeared.