Self-similarity of obliquely impinging jet heat flux fields in a range of Mach numbers from 0.1 to 1.0.

• Reveal the self-similarity (Mach-number-invariance) of the normalized time-averaged surface heat flux in an obliquely impinging jet in a range of the nozzle exit Mach numbers from 0.1 to 1.0. • Conduct temperature sensitive paint (TSP) measurements in an obliquely impinging jet in a range of the Mach numbers from 0.1 to 1.0. • Elucidate the origin of this self-similarity based on a semi-empirical model proposed for the maximum surface temperature difference used for normalization,. • Exhibit self-similarity is also found in the normalized root-mean-square (RMS) fields of the heat flux fluctuation and the normalized skin friction fields. This study reveals self-similarity (Mach-number-invariance) of the normalized time-averaged surface heat flux fields measured using temperature sensitive paint (TSP) in an obliquely impinging jet in a range of the nozzle exit Mach numbers from 0.1 to 1.0. Further, this self-similarity is also found in the normalized root-mean-square (RMS) fields of the heat flux fluctuation and the normalized skin friction fields extracted from the surface temperature and heat flux fields. To elucidate the origin of this self-similarity, a semi-empirical model is proposed for the maximum surface temperature difference used for normalization, indicating that the Mach number effect on the impinging jet heat transfer is mainly represented by the recovery temperature at the impingement point. [ABSTRACT FROM AUTHOR]