Analysis of the principle and working mode of thermostatic hot-wire anemometer
Principle and working mode of constant temperature hot wire anemometer:
1, is an electrically heated fine metal wire (called hot wire) placed in the airflow, the heat dissipation of the hot wire in the airflow is related to the flow rate, and the heat dissipation leads to changes in the temperature of the hot wire caused by changes in electrical resistance, the flow rate signal that is converted into an electrical signal.
The working mode of constant temperature hot wire anemometer:
1,Constant current type: the current through the hot line remains constant, when the temperature changes, the resistance of the hot line changes, thus the voltage at both ends changes, thus measuring the flow rate.
2, constant temperature type: the temperature of the hot line remains constant, the current to the wind speed sensitive components can be adjusted, in different wind speeds so that the wind speed sensitive components in different thermal equilibrium state of the working temperature is basically inconvenient, that is, the resistance value is basically constant, the power consumed by the sensitive components as a function of the wind speed.
Above is the product principle and working mode explained for you, then I next further explain what are the characteristics?
Constant temperature hot-wire anemometer features:
1, small size, small interference with the flow field.
2, high measurement accuracy, good repeatability.
3, high frequency response, can be as high as 1MHz.
4, the disadvantage is that there is a certain interference with the flow field, the hot line is easy to break.
5, a wide range of applications, can be used for gas, liquid, in the gas subsonic, transonic and supersonic flow can be used; in addition to measuring the average velocity, but also can measure the pulsation value and turbulence; in addition to measuring the single-direction movement can also be measured at the same time more than one direction of the velocity component.
