'Flow Characteristics of Skimming Flows in Stepped Channels' by I. Ohtsu, Y. Yasuda, and M. Takahashi

摘要

The discussers congratulate the authors for their systematic study of skimming flows on stepped channels with different slopes and step heights. Their experimental data provide a solid database that might lead to better and improved design criteria. Important outcomes include some estimate of the friction factors for skimming flows and a design flowchart for stepped canals. Despite these outstanding results, the discussers would like to comment constructively on further design criteria for skimming flows and to provide additional flow-resistance results and a discussion on the physical processes.