Study of Non-Contact Type Flowmeter for Low Flow Rates Using Near-Infrared Light

Abstract

We have proposed a novel method of non-contact thermal type measurement for low flow rates using radiation heating and spectroscopy of water in the near-infrared wavelength range . We made a simulation for studying the performance of the flowmeter, and based on the simulation we conducted experiments using a prototype flowmeter. We obtained calibration curves between the estimated and true flow rates. From the experimental results , we can measure the flow rates from 0.3 to 9 ml/ min with the accuracy of about 10% of the flow rate . We also obtained agreement between the simulation and measurement results. Discussions are made to improve the measurement accuracy .