DESCRIPTION

Technical Description

Sharp-crested weirs are a type of control structure that dam up an open channel in a defined manner. They are often used to determine the discharge of an open channel. 

HM 150.03 contains two different plate weirs as sharp-crested weirs. The two weirs are typical measuring weirs with defined weir openings: in the Thomson weir the opening is triangular; in the Rehbock weir it is rectangular.

The weirs are installed and screwed in place into the HM 150 base module. The weir can be installed and replaced quickly and easily.

Water from the small experimental flume in HM 150 flows over the weir being investigated. A level gauge for detecting the head is included in the delivery. The head is used to determine the discharge, which is then compared to the measured values from HM 150. 

The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

Learning Objectives / Experiments

- free overfall at the sharp-crested weir
- plate weirs as measuring weirs
  * determining the discharge coefficient
  * comparison of measuring weirs (Rehbock, Thomson) 
- determining the discharge
- comparison of theoretical and measured discharge