组合热膜式流速矢量传感器

Abstract

To realize the measurement of the air flow vector on a Micro Air Vehicle(MAV),a new type of hot-film anemometer which was lighter than a pitot and firmer than a hot-wire anemometer was developed and a corresponding combined system was also presented. Similar to the hot-wire anemometer,the hot-film anemometer is sensitive to both magnitude and direction of flow speed,and its output is a resistance when either the flow magnitude or direction changes.Moreover,by combining the sensor array simply, the flow speed vector could be acquired in a angle range,and thus its application area was expanded.Based on the experimental tests on the sensor characteristics,the principles and conditions of the combination scheme were researched,the method to arrange the sensor array was given and the speed vector measuring error was discussed.The experimental results indicate that arranging 3 hot-film anemometers with a separation angle of 45° to form a combination system can measure the flow vector in the angle range of 180°.Both of theoretical and experimental results prove that the presented combination method is effective and feasible,and its volume and energy consume are both lower than those of traditionnl methods.It can be further expanded to other flow sensors with similar characters.