Abstract
This thesis shows the development of a thermal microsensor with calorimetric operation for the shear stress measurement. Its operating principle is based on the modification of thermal exchanges in a heated fluid. Among other things, this sensor has the advantage of measuring the change in flow direction, an important characteristic in the detection of the boundary layer separation. One of the objectives of this thesis is to develop the performance of this sensor in order to meet the requirements of the measurement of more or less important fluctuations of the fluid on the surface. In this context, the development of a numerical model, then the elaboration of microfabrication processes, and finally the characterization in a wind tunnel of four main structures allowed the realization of a geometrical and structural study of the sensor. Areas of improvement on sensitivity, measurement range and mechanical robustness are presented and several applications of the sensor to the detection of near-wall aerodynamic phenomena and in particular the flow separation are studied.