LAUSR

A thermal based acoustic vector sensor consisting of three heated wires can detect the acoustic particle velocity instead of pressure. This paper proposes an analytical model for calculating the temperature distribution and acoustic caused temperature perturbation of the sensor with three-hot-wire configuration. In this model, the nonlinear effect caused by nonuniform thermal conductivity is considered. The nonlinear effects will not only affect the temperature of three hot wires, but also the frequency response of the sensor. According to the stationary temperature distribution calculated by nonlinear model, we correct the heat diffusion coefficient in acoustic perturbation model. The nonlinear stationary model and corrected perturbation model are found to be in good agreement with numerical results. What’s more, we design a chip to measure the temperature distribution of three heated wires and compare the sensitivity of the sensor with corrected model. The experimental results can verify the proposed model. This study provides a theoretical basis for sensor performance optimization.