Wind Tunnel Wind Velocity Profiler and Its Control Method

Abstract

The invention relates to a wind-tunnel wind profiler and a control method thereof. The wind-tunnel wind profiler comprises a data acquisition portion, a wireless data transmission portion and a control processing device. The data acquisition portion comprises a plurality of hot-film probes and a data acquisition card. The wireless data transmission portion comprises a wireless transmitting deviceand a wireless receiving device. The hot-film probes are connected to the data acquisition card. Wind speed signals acquired by the hot-film probes are converted into voltage signals after being calibrated, and then the voltage signals are transmitted to an Analogue-to-Digital (A / D) converter in the data acquisition card, so that the data acquisition card completes the acquisition of the wind speed signals output by the hot-film probes and transmits the wind speed data acquired to the wireless transmitting device; next, the wireless transmitting device transmits the wind speed data received to the wireless receiving device in a wireless way; and the control processing device is connected to the wireless receiving device. The wind-tunnel wind profiler has the characteristics of being simple in structure, feasible in performance, low in cost, convenient for carrying and installation, simple in field wire connection, and flexible and reliable in use.

Description

technical field [0001] The invention relates to a wind tunnel wind speed profiler and a control method thereof, in particular to a wind tunnel wind speed profiler based on a hot film sensor and a wireless sensor network and a control method thereof. Background technique [0002] Soil wind erosion is the primary cause of land desertification and sandstorm disasters in arid, semi-arid and partially sub-humid areas, and is also one of the major environmental problems in many countries and regions in the world. Sand movement is as harmful as natural disasters such as floods, droughts and storms. It can bury farmland and pastures, destroy crops and blow away topsoil and seeds, seriously eroding the land on which human beings depend. At the same time, wind and sand movement can also hinder traffic, bury railways and highways, and endanger driving safety. [0003] In my country, the Institute of Environment and Engineering in Cold and Arid Regions of the Chinese Academy of Science...

AI Technical Summary

Problems solved by technology

[0006] figure 1 The wind speed measuring device shown in has the following defects: (1) the system uses a pitot tube and a long rubber tube as the main measuring element, and the sensitivity and accuracy are poor

In a certain range of wind speed, the absolute value of air pressure measured by pitot tube is much smaller than the differential pressure value measured by static pressure difference. The measurement error of differential pressure sensor is certain, and the result will lead to relative error of velocity pressure measurement results. Therefore, the Pitot tube is only suitable for the measurement conditions with wind speed greater than 4m / s; and when working in the field, the pressure measuring hole of the wind speed sensor may be blocked by dust or sand in the air and lose the speed measurement function

In addition, when the rubber tube connecting the pitot tube and the differential pressure transmitter is long, the rubber tube is easily bent and deformed, resulting in a decrease in measurement sensitivity

Moreover, due to the inertia of the measurement system, it takes a certain amount of time for the measurement medium and the measured medium to reach equilibrium, which causes a certain time delay for the pulsation change of the airflow. In the high-frequency pulsation airflow, the measurement result will be smaller than the actual value.

(2) There are too many connections in the measuring device, and it is inconvenient to move the measuring point

When measuring wind speed in the field, the measuring point will move at any time, and the existing wind speed collection and data processing devices are connected together, which needs to be installed and disassembled when moving, which brings uncertainty to the accuracy and accuracy of the measurement results , and it is inconvenient to use

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