Thermoelectric cool-film shear stress sensor

Hot-wire anemometers, being a robust and highly sensitive method for measuring flow properties, can be limited in sensitivity where locally increasing the temperature may induce measurement inaccuracy such as when used in near-boiling fluids. In this environment, locally decreasing the temperature allows for a larger temperature difference between the sensor and the ambient environment, thereby increasing device sensitivity while maintaining single-phase convection heat transfer physics. In this letter, we present the new capability of using thermoelectrically cooled sensors to measure wall shear stress. The power required to maintain a constant sensor temperature was increased as the wall shear stress in the channel was increased, providing proof of concept.