Design and characterisation of customised-roughness beds for open-channel flow experiments

Abstract

The use of laboratory channels or flumes for open-channel flow research is widespread. However, this type of equipment is often expensive, susceptible to damage, and require regular maintenance. In open-channel flow, the roughness of the channel bed is a critical property in governing the flow characteristics. Unfortunately, changing the bed properties, particularly its roughness, proves to be a challenging and time-consuming task in most laboratory channels. To address these limitations, this stud introduces a novel and cost-effective technique to build laboratory channel beds with tailored roughness. Additionally, we describe a precise photogrammetric-based method for quantifying the absolute roughness of the bed. These engineered beds can be seamlessly integrated into various laboratory channels without posing any risk of equipment damage. In addition, they offer the flexibility to be modified to meet specific roughness conditions, thus advancing the capabilities of experimental setups in hydraulic studies Furthermore, these specially designed beds can find utility in other facilities where control of surface properties is necessary.