A Numerical Investigation on Convective Accelerometer

Aim of this paper is to investigate an innovative, low – cost, non-intrusive technique for measuringan arbitrary acceleration vector, belonging to a reference plane. The technique is based on freeconvection and allows computing the acceleration magnitude as a function of the temperatureimbalance across four sensors, located within a cavity. The dual-axis convective accelerometermakes use of the relationship existing between the Grashof number and the acceleration vector. Thetechnique shows good linearity, sensitivity and frequency response. The use of a four-sensor clusterallows obtaining the acceleration direction. The shape and the size of the enclosure, as well as thelocation and the number of sensors considerably affect the response of the system. Therefore, aparametric analysis is carried out by numerical simulation. Finally, some hints are provided for thedesign and the tuning of the measuring device. The numerical simulation is carried out using afinite-volume-based ‘projection method’, accurate to the 2nd order in both space and time.Some hints for the designer are finally given based on the dimensional analysis of the device.