Hydraulics Field Observation
Embedded Files
1- Location: Logan River
Date of observations: February 8, 2025
41.7428321, -111.7639979
Location of observations in relation to downtown Logan.
2- Field Map Sketch
3- Channel Flows
Arrow represent flow within the channel and the size of the arrows represents the magnitude of flow.
This section of the river reflects convergent and divergent flow as well as a chute, wake and ripples.
Shear Zones: Eddy Vs. Wake
LEFT: An example of a wake, where the direction of flow remains the same on the downstream side of an obstacle, such as the boulder in the photo.
RIGHT: An Eddy is caused by a river irregularity. Water is circulated in the opposite direction of the river, creating an eddy.
Each shear zone reflects Flow Seam(s) and Flow Separation Point(s), also known as detachment points.
Neither of these examples provide a very good example of a reattachment zone.
4- Estimated Discharge
Discharge: Q=VA can be roughly calculated to be
11.25 m^3/s.
This calculation was done using the Orange Peel Method and rough estimates of the cross sectional area of this location in the river.
5- Cross Section
This stretch of the river had large cobbles and some boulders. The channel was relatively uniform in depth.
6- Hydraulic Jump
Hydraulic Jump:
Is a transition from Supercritical to Subcritical Flow.
This photo and video provide an example of a small hydraulic jump in the Logan River. Supercritical flow can be seen flowing shallowly over a rock with a Hydraulic jump at the bottom where the flow then transitions into subcritical flow as is deeper.
*The Upstream subcritical flow is not very well represented in this photo.
Page updated
Google Sites
Report abuse