摘要
With measurements of boiling curves and bubble dynamics, this paper experimentally investigates the effects of heating orientation on the boiling characteristics under the downward facing heating condition. The boiling curves and bubble dynamics for various heating angles are measured. Based on the present data, the boiling heat flux increase with the decreasing heating angles. This enhanced effect is insignificant in the higher heat flux region, similar to the previous work. Combined with the data in the merged slug bubble region from Kim et al., the present measured bubble dynamics in the discrete bubble region can give the overall picture of boiling heat transfer and bubble dynamics for the whole nucleate boiling. In addition, the present data including boiling curves and bubble dynamics can provide the valuable information for the in-depth understanding of the boiling characteristic and the benchmark of boiling models for the downward facing heating.