1 / 14

Flow Routing

Flow Routing. Learning Objectives Calculate outflow hydrographs for reservoirs using the storage indication method Calculate outflow hydrographs for stream reaches using the Muskingum method Reading: 8.5 and 8.6 in text 9-3 in EM 1110-2-1417. Flow Routing.

ralph-osborne
Télécharger la présentation

Flow Routing

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Flow Routing • Learning Objectives • Calculate outflow hydrographs for reservoirs using the storage indication method • Calculate outflow hydrographs for stream reaches using the Muskingum method • Reading: • 8.5 and 8.6 in text • 9-3 in EM 1110-2-1417

  2. Flow Routing • Flow, or flood, routing – process of determining the outflow hydrograph from a reservoir or stream reach for a particular inflow hydrograph • Streamflow Routing – technique to compute the effect of channel storage on the shape and movement of a flood wave

  3. Inflow and outflow from a reservoir Inflow exceeds outflow and the reservoir is filling Outflow exceeds inflow and the reservoir empties Inflow and outflow are equal and maximum storage is reached

  4. Reservoir Routing – process of determining the outflow rate from a reservoir for a particular inflow hydrograph Level Pool Routing – process for calculating outflow from a reservoir assuming horizontal water surface when given inflow and storage-outflow characteristicsBased on the Continuity Equation:

  5. Values for I1 and I2 are specified by the inflow hydrograph. Equation 1 contains two unknowns, O2 and S2. • Get a relationship between water surface elevation and reservoir storage by topographic maps or field surveys. • Get a elevation-discharge relation from hydraulic equations relating head and discharge for the type of outlet. • Dt is the time interval of the inflow hydrograph

  6. Central Branch Webb Branch 1000 ft. 1002 ft. 1006 ft. 1004 ft. Step 1 – Develop a stage-storage relationship for the pond

  7. Step 2 – Develop a stage-discharge relationship for the outflow structure

  8. Step 3 – Plot outflow (O) as a function of S/t+O/2 = Storage-indication curve

  9. Step 4 – Route flow through structure, assuming initial outflow equals initial inflow Inflows for the storm are given. Assume inflow = outflow for the first time step. Using the assumed outflow, find S1/Dt - O1 /2 for the first time step ONLY from the storage-indication graph and solve for the initial storage volume. For the second and remaining time steps, calculate Si/Dt - Oi/2 and add it to the average inflow (Ii + Ii+1)/2 to determine Si+1/Dt+ Oi+1/2. Use chart to get Oi+1 and then calculate Si+1. Start again at next time step.

  10. Step 5 – Plot inflow and outflow hydrographs

  11. Flow Routing • Learning Objectives • Calculate outflow hydrographs for reservoirs using the storage indication method • Calculate outflow hydrographs for stream reaches using the Muskingum method • Reading: • 8.5 and 8.6 in text • 9-3 in EM 1110-2-1417

More Related