Application of power law in shallow open channel flows

• Main Author: Tan, Jian Ming.
• Other Authors: Cheng Niansheng
• Format: Final Year Project
• Language: English
• Published: 2011
• Subjects: DRNTU::Engineering::Civil engineering::Water resources
• Online Access: http://hdl.handle.net/10356/45133
• Institution: Nanyang Technological University

The knowledge of rough bed flow is essential for open channel hydraulics as flow in rivers can be considered as hydraulically rough and channel morphology and local bed friction are major contributors to flow resistance.Many researches were conducted for open channel flow with large relative submergence but few researches were conducted for flow with low relative submergence in an open channel. The hydraulics of shallow open channel flow is therefore poorly understood. This research aimed to measure the velocity distribution in a shallow open channel flow with sediment height to flow depth ratio less than 4 using a Particle Image Velocimetry (PIV). Seven sets of experiment were conducted using a 0.3m wide flume with varying flow depths from 1.8cm to 7.6cm and gravels of diameter D50 equal to 3.28cm were used as the sediment to simulate a gravel bed open channel. The statistical stability of the velocity data are analysed with respect to time and space obtained using the PIV. The velocity data are then compared with the power law to ascertain if a relationship exists.