Capacitive flowmeter for gas-solids flow applications exploiting spatial frequency

Abstract

Non invasive flow measurement principles are required in various industrial and agricultural applications. Among other principles capacitive sensing offers an elegant solution to measure granular material flow. In this paper the principle of spatial filtering, which is widely used in the world of optical measurement, is applied for a capacitive flow meter. The paper introduces a useful electrode geometry as well as potential electrode excitation modes. The principle is tested and verified by means of simulations. To show the practical usability a flow sensor based on spatial filtering was built up and tested in a laboratory setup.