スピンアップ過程における渦崩壊の発生機構に関する数値的研究

概要

論文の詳細を見る
A Numerical study presented on a vortex breakdown in spin-up process in an enclosed cylindrical container. In a transitional state, momentary vortex breakdowns can occur for particular parameter values ofthe Reynolds number and aspect ratio where no vortex breakdown appears in a steady state. This transient vortex breakdown flow is convenient to consider a mechanism for the occurrence of a vortex breakdown. It isdiscussed that periodical increase and decrease of angular momentum in upstream of the flow leads to the occurrence of momentary vortex breakdown. Regions for momentary vortex breakdown in spin-upoccurrence are shown in the Re-H/R plane for comparison with regions for steady vortex breakdown occurrence. The character of the regions for momentary vortex breakdown where no upper limit of Reynoldsnumber exists is found to be very different from that of the regions for steady vortex breakdown.
東京都立産業技術高等専門学校の論文