Modeling, Simulation, and Fabrication of a 2-D Anemometer based on a Temperature-Balanced Mode

A 2-D anemometer sensor on a ceramic substrate is proposed, modeled, simulated, and fabricated. The sensor consists of four outlying heaters and four inlying thermistors arranged in two orthogonal directions on a ceramic substrate. The heaters are driven by power feedback control circuits, while the thermistors measure the temperature distribution on the surface of the sensor. By applying a power difference on the upstream and downstream heaters, the flow-induced temperature gradient is canceled via the temperature-balanced mode, and both wind speed and direction can be extracted by the applied power difference. An analytical model of the 2-D anemometer sensor is developed for the applied power difference as a function of wind speed and direction. The finite-element method simulations have been utilized to demonstrate the analytical model. The sensor was fabricated directly on the ceramic substrate by using a typical lift-off technology. The sensor output was measured and compared with the theoretical model. A high measurement accuracy has been achieved from 0 to 40 m/s with a speed error less than ±0.5m/s and a direction error of less than ±2°.