Ultrasonic wind speed sensor is a full digital signal detection instrument, which can calculate the wind speed through the time of ultrasonic transmission in the air. It is widely used in mines, forests, weather monitoring and other fields.
Ultrasonic wind speed sensor is mainly the use of ultrasonic time difference method to achieve the measurement of wind speed, sound in the air propagation speed, and the wind up the airflow speed superposition. If the ultrasonic wave travels in the same direction as the wind, it speeds up. Otherwise, it will slow down. Therefore, under fixed detection conditions, the transmission speed of ultrasonic wave in the air can be corresponding to the wind speed function and accurate wind speed and direction can be obtained through calculation.
Principle of pressure difference change:
A fixed obstacle (orifice plate, nozzle, etc.) is placed in the direction of movement so that a differential pressure will occur depending on the flow rate. After measuring the pressure difference, it can be converted into a measurement of the flow rate.
Heat transfer principle:
In no limit flow straight into a nonlinear resistance body of infinite length (i.e. body vortex attack C, wind speed sensor probe bar), when the wind through the spiral attack body C, on the edge of the whirlpool attack body dirty side will attack within two rows of alternate, spiral vortex column (i.e., air flow vortex), and the onset of vortex frequency f is proportional to the velocity V, with a formula that is as follows:
Based on the above formula, we can also draw the following conclusion that when a barrier is set between the wind speed sensor and the transducer, two rows of alternating vortexes will be generated below the barrier when the flowing air passes through it.
Because of the blocking effect of vortex on ultrasonic wave, ultrasonic transducer will receive ultrasonic wave with the intensity of vortex frequency change, when the vortex does not block ultrasonic wave, the intensity of ultrasonic wave received is the largest; When the vortex just blocks the ultrasonic wave, the intensity of the received ultrasonic wave is the smallest. The ultrasonic transducer sends the received frequency signal to the frequency/voltage conversion module and converts it into voltage. The two are linear proportional relationship, that is, voltage and wind speed are linear proportional relationship. So ultrasonic wind speed sensor is to use the principle of ultrasonic vortex modulation to measure the vortex frequency.
To sum up, it can be seen that ultrasonic wind speed sensors in many places bring people not only data, but also safety protection, while the traditional method of wind speed, wind volume measurement, often has low accuracy, high cost, poor stability and other problems.
The ultrasonic wind speed sensor of JXCT measures the wind speed by using the influence of the velocity of ultrasonic wave in the air. Compared with traditional anemometer, the biggest characteristic of this method is that the whole wind measuring system does not have any mechanical rotating parts. Inertial measurement can accurately measure the high frequency component of gust pulsation in the natural wind.