A four-wire micro anemometer in double cross shape with high mechanical stability for high sensitive air flow

Abstract

Wind sensors are applied in a wide variety of applications from air forecasting to aerospace. In proportion to different demands on sensing range of flow, different Materials and structures with different sensing principles can be used. In this paper, a novel and highly sensitive wind sensor with four suspended hot wires with promising mechanical strength is presented. The sensor works in the constant power mode and the consistency between the simulation results and the experimental curves verified the correctness of the sensor. The narrow and trapezius shape silicon (Si) substrate with 40- μm thickness was considered to increase the stability of the wires at high speed (up to 30 m/s) and other physical damages in harsh places. Initially, to verify the validity of the sensor function for wind speed and direction detection, 3D models of the thermal wind sensor was built with COMSOL Multiphysic software. The difference in the resistance among the hot wires is a measure for the air velocity. The testing results indicate that the accuracies of the wind sensor are in the range of 0.2 m/s and ± 5° at wind speed ranging from 0 m/s to 10 m/s and wind direction from 0° to 360°, respectively.