Measurement principle of digital hot bulb anemometer:
There is a tiny wind speed sensor (glass ball) on the top of the probe of the thermal ball anemometer, and a nickel-chromium wire coil (heating coil) and a thermocouple are burned in the ball. The sensor is directly exposed to the airflow. When a certain amount of current passes through the heating coil, the glass ball is heated to a certain temperature. At this time, a corresponding thermoelectric potential appears at both ends of the thermocouple. When in still air (the wind speed is zero), the thermoelectric potential is a fixed value; when measuring the wind speed, the airflow makes the temperature of the working environment of the thermocouple drop, and the thermoelectric potential at both ends of the thermocouple changes, and its value is a function of the wind speed. Therefore, the corresponding wind speed value can be calculated by measuring the thermoelectric potential.
Thermal bulb anemometers are especially suitable for measuring light wind speed, such as 0.1-0.5m/s wind speed is its advantage, and its accuracy and stability are better than other forms of thermal anemometers.
