基于二极管的热式流量传感器的设计与实现

Design and realization of thermal liquid mass sensor by using diodes

设计并实现了一种基于二极管的热式流量传感器.传感器由两个感温二极管和一个加热电阻构成,其中一个二极管作为测温元件感测流体温度,另一个二极管和电阻封装到一起感测流体流速.使用Multisim软件对包含传感器的桥式电路进行了仿真,分析了输出信号与两个二极管温差的关系.并设计了以单片机为核心的信号测量处理电路,给出了流量为10~100 L/h的测量结果.

A thermal type flow meter for liquids that using two diodes was presented.The sensor was composed by two diodes which act as thermal sensors and a resistor acts as thermal feed-through.A CPU-included sensor control circuit was designed to find the fluid temperature by using one diode and the fluid flow rate by using the other which was glued to the resistive heater.The theoretical analysis was performed by using Multisim software,and the results of water flow tests in the range（10 ~ 100） L/h were presented.