Thermofluiddynamic experiments with a heated and rotating circular cylinder in crossflow: Part 1: Subcritical heat transfer measurements

Heat transfer experiments with a heated and rotating circular cylinder in an air crossflow were performed for subcritical freestream-Reynolds-number 8.3 · 10³ < Re_f < 7.1 · 10⁴ and for Nusselt-numbers up to 300. The experiments took into consideration important practical parameters such as freestream-turbulence intensity, aspect ratio, blockage ratio and temperature loading. The measured values were standardized to the 'idealized case' to allow adequate comparison with pertinent literature. The results encompass the range of velocity ratios α (circular/freestream-velocity) between zero and 2.5. For values α > 0.5, the typical Nusselt-number behaviour noted by some authors has been confirmed. For small velocity ratios α < 0.5, however, there are significant deviations from the heat transfer coefficients previously believed to be constant.