A preliminary study on calibration-free hot-wire anemometry method

The study aimed to investigate convective heat transfer from a heated circular cylinder with a diameter of 5 microns and a length-to-diameter ratio of approximately 200 or more using experimental methods. A new relationship between the Nusselt number and the Reynolds number was proposed. The results obtained from this study and those reported in the literature were fitted linearly to a curve. This curve served as the basis for proposing a novel hot-wire velocity measurement technique. In this method, velocities are directly calculated from the voltage outputs of the anemometer without requiring calibration. However, validation measurements indicated that there were errors of up to 23% between the measured and actual values. These errors may be due to measurement uncertainties in the probe's length, cold resistance measurement, the resistance of the lead wire, and connectors.