A new sensor to measure fluid velocities: The Peltier anemometer

This paper introduces a new approach to the measurement of low fluid velocities. A new type of anemometer is presented, resorting to a sensor directed to measuring low velocities (> 2 x 10(-2) m s(-1) in air) with a precision to the nearest 5 x 10(-2) m s(-1). The device works owing to the thermoelectric effects, especially the Peltier and Seebeck ones. It is non-invasive since its increase in average temperature remains lower than 15 K. Therefore low-velocity measurements can be carried out without any significant perturbation. A coherent design rationale is formulated and the various stages in the technical development of the system are delineated. A compensating technique is described in order to provide reliable performance over temperature variations. In most cases this sensor can be instrumental in studying mechanisms of natural convection.