The study of water-head measurement shown in a single tube manometer by use of easy image-processing technique

National Defense Academy of Japan, Department of Mechanical Engineering, 1-10-20 Hashirimizu, Yokosuka 239-8686, Japan

^* Corresponding author: yokoi@nda.ac.jp

Published online: 28 June 2019

Abstract

This study proposes the technique which can perform pressure measurement by the low flow velocity which is performed by flow visualization. The technique is the following. The water level image accompanied by the scale shown in a single tube manometer is photographed with a digital camera or a digital camcorder. And image-processing measurement of the image data is carried out in the length of the water level by computer. As verification of the technique, the measurement comparison result of the pressure distribution on the surface of a circular cylinder set in the stream was compared with the previous result. The result was good. It proved that the technique is measurable also by a minute water-head. Furthermore, examination was performed about the validity, the reliability, and the operativity of the technique. As a result, even if who did operation of image-processing measurement, it was shown that high resolution and good accuracy are obtained.