Many examples of open channel flow can be approximated as uniform flow allowing the Manning equation to be used.  Non-uniform flow calculations are needed, however, in some open channel flow situations, where the flow is clearly non-uniform.  The concepts of supercritical, subcritical and critical flow, and calculations related to those three regimes of flow, are needed for non-uniform open channel flow analysis and calculations. In this course, the parameter called specific energy will first be used to introduce the concepts of critical, subcritical, and supercritical flow.  Various calculations related to critical, subcritical and supercritical flow conditions will be presented, including hydraulic jump calculations.  The thirteen possible types of gradually varied non-uniform flow surface profiles will then be presented and discussed.  Also, the procedure and equations for step-wise calculation of gradually varied non-uniform surface profiles will be presented and illustrated with examples. This course is intended for hydrologists, civil engineers, hydraulic engineers, highway engineers and environmental engineers.  An attendee of this course will gain knowledge about the meaning of critical, subcritical, and supercritical flow, about basic calculations related to those three types of flow, about the hydraulic jump and basic calculations concerning it, about the classification scheme for types of gradually varied non-uniform flow, and about how to carry out a stepwise calculation of a gradually varied, non-uniform flow surface profile.  Upon completing this course, the student will be prepared to take additional open channel hydraulics courses.

Learning Objectives

• Determine the critical depth for a specified volumetric flow rate through a rectangular channel of specified bottom width, as well as through an open channel of specified shape, size, & Manning roughness coefficient with known critical depth.
• Distinguish whether a specified volumetric flow rate through an open channel of given shape & size, with known depth of flow will be critical, subcritical or supercritical flow.
• Calculate the depth of flow after a hydraulic jump if given the depth before the hydraulic jump, the volumetric flow rate and the shape and dimensions of the open channel.
• Identify which type of surface profile (e.g. M1, M2, M3, S1, S2,  S3, etc.) is present in a specified gradually varied flow situation.
• Compute a stepwise calculation of the surface profile for a specified, gradually varied, non-uniform open channel flow.