Different Models Required (Reservoir)

In previous chapter we discussed about the Models required and discussed our second fundamental model (HD Model). In this chapter I will discuss about reservoir model.

Reservoir model deals with the flow to the reservoir, outflow and the level of reservoir. There are various techniques used. Some person skip the HD model and directly use Reservoir model. Now you know that it will alter accuracy. 

I am using HEC ResSim software as Reservoir Model. It is simple and open source. The purpose of using Reservoir Model is very simple. 

I have the inflow, Outflow is also in my control, I want to know the level of reservoir for a controlled outflow or vice versa. 

You can also put your own rating curves and rules so that the reservoir automatically controls the outflow as per current inflow and level of the reservoir. 

To make a model you will need river profile. Then you have to mark your reservoir.The model of ResSim is shown below.

Now comes the tricky part. In reservoir you have to add few things.

1) EAV (Elevation area volume)

To calculate the exact level it needs the elevation, area and volume table of the reservoir. You can calculate it using Arc GIS or by doing a survey of reservoir (Lidar or Echo Sounder). The EAV of the reservoir changes because of the incoming silt. EAV table looks like:

Then you have to insert a controlled outlet. If you have gates you can add the elevation of gates and their dimensions (max outflow through them).

After that you create rules for the operation of the reservoir. You can add any type of rules according to your requirement such as flood control, conservation etc. You can add the level and outflow of it. 

ResSim gives you multiple scenarios or options to play with. You can calculate ensembles, level of reservoir for constant outflow/ time series. This will help in better operation of reservoir. As you can guess what will happen in future with this easy to use software.

Note:- Inflow to reservoir must be added (from Hydrodynamic model or Hydrological model)

After all the setting you go and run a simulation to see your results. Simulation is simple add date and time and press ok to create a simulation. Then run it. The simulation window looks like :

In next chapter I will discuss about Real Time Simulation and it's concepts. I am working on a software which is publicly released on July 13th  2017. I am working on different versions of that software since 2014.