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This paper presents construction and performance of a novel hybrid microelectromechanical system (MEMS) vortex flowmeter. A miniature cantilever MEMS displacement sensor was used to detect frequency of vortices development. 3-mm-long silicon cantilever, protruding directly out of a trailing edge of a trapezoidal glass-epoxy composite bluff body was put into oscillatory motion by vortices shed alternately from side surfaces of the obstacle. Verified linear measurement range of the device extended from 5 to 22 m/s; however, it could be broadened in absence of external 50-Hz mains electrical interfering signal which required bandpass frequency-domain digital sensor signal processing. The MEMS vortex sensor proved its effectiveness in detection of semilaminar airflow velocity distribution in a 40-mm-diameter tubular pipe.\hfill[2010-0164] [ABSTRACT FROM AUTHOR]

Images of the electron density of a magnetized electron column illustrate the dynamics of intense vortices moving in a weaker background vorticity. A moving retrograde clump of vorticity generates a spiral wake that then evolves into many long-lived holes, contributing to the late time fluctuations. [ABSTRACT FROM AUTHOR]