EXPERIMENTAL INVESTIGATION ON VORTEX BREAKDOWN IN SPIN-UP AND SPIN-DOWN PROCESSES VIA PIV  

作　　者：LiuYing-zheng KoyamaHideS. ChenHan-ping 

机构地区：[1]DepartmentofPowerMachineryEngineering,ShanghaiJiaotongUniversity,Shanghai200030,China [2]DepartmentofMechanicalEngineering,TokyoDenkiUniversity,Tokyo101-8457,Japan

出　　处：《Journal of Hydrodynamics》2003年第2期58-63,共6页水动力学研究与进展B辑（英文版）

摘　　要：The whole field measurements of swirling flow in spin-up and spin-downprocesses via PIV are presented in the paper. Investigation of the flow patterns at H/R = 1. 50 wasexperimentally carried out for the first time in both processes. By means of symmetry analysis, itis found that the overall flow structure in the spin-up process still keep axi-symmetric to a greatextent, but deteriorated very fast in the spin-down process. The time to settle to the state of restin the spin-down process is found to be greatly shorter than the time to achieve the steady statein the spin-up process. Temporarily oscillatory vortex breakdown was discovered during the spin-upprocess, although no breakdown in the steady state at the same Reynolds number is found in preciousresearches.The whole field measurements of swirling flow in spin-up and spin-downprocesses via PIV are presented in the paper. Investigation of the flow patterns at H/R = 1. 50 wasexperimentally carried out for the first time in both processes. By means of symmetry analysis, itis found that the overall flow structure in the spin-up process still keep axi-symmetric to a greatextent, but deteriorated very fast in the spin-down process. The time to settle to the state of restin the spin-down process is found to be greatly shorter than the time to achieve the steady statein the spin-up process. Temporarily oscillatory vortex breakdown was discovered during the spin-upprocess, although no breakdown in the steady state at the same Reynolds number is found in preciousresearches.

关 键 词：vortex breakdown PIV swirling flow 

分 类 号：O351.3[理学—流体力学]