Method for Measuring Turbulence by a High Speed Image Procession Using an Area Type Image Sensor

Abstract

A method for measuring fluid turbulence with an aid of an area-type image sensor is developed in this work. The equipment consists of a probe, an area-type image sensor having a parallel scanning mode and a circuit for high-speed processing of signals from the image sensor. The role of the probe, consisting of an image fiber, a light guide fiber and a micro lens, is mainly to transfer accurately the images of tracer particles flowing into a small observing space set in a unit toward the image sensor. The roles of the circuit are to digitize the analog signals from the sensor to let the processed signals under a particular mode be memorized by the RAM.
The flow velocity of liquid in a stirred vessel was measured by using this proposed method, as a demonstration. The power spectra of turbulence in two flow directions are shown in this paper.
It may be possible to measure not only mean flow velocity but also liquid turbulence in any unit by applying this method.