Method for Measuring Flow Velocity Based on Periodic Heating and MEMS Techniques

摘要

A method to measure fluid flow velocity is developed by means of periodic heating and a micro flow sensor based on MEMS techniques. The sensor consists of a heater and a temperature sensing unit. When an AC voltage is applied to the heater, the output from the temperature sensing unit becomes a phase-delayed sinusoidal wave. The magnitude of the phase shift reflects the fluid velocity. A numerical model is also developed. It has been shown that the numerical model can correctly predict the characteristic trends of experimental results.