SIC^2: Simulation and Integration of Control for Canals

Volume indicators

David Dorchies — 2009-10-22T15:33:51Z

The volume indicators refer to three kind of volumes:

The demand volume (V_D), which is the target volume at the offtakes,

The supply volume (V_S), which is the volume supplied at the offtakes,

The effective volume (V_EF), which is the really usable part of the supply volume.

The definition of the effective volume depends on two coefficients: W and X (in %):

if (1-W/100).Q_D <= Q_S <= (1+X/100).Q_D => Q_EF = Q_S
if Q_S < (1-W/100).Q_D => Q_EF = 0
if Q_S > (1+X/100).Q_D => Q_EF = (1+X/100).Q_D

All volumes are calculated with trapezoidlal rule:

$$V = \frac{t_d-t_f}{\Delta t} \left( \frac{f(t_d) + f(t_f)}{2} + \sum_{k=1}^{n-1} f \left( t_d+k \frac{t_d-t_f}{n} \right) \right)$$

Only the supply discharge close to the water demand is thus taken into account (see below).


Graph indices volumiques

In this figure the effective volume is shaded. We define three volume indicators:

Indicator IND1 = V_S/V_D
Indicator IND2 = V_EF/V_D
Indicator IND3 = V_EF/V_S

These indicators can be defined for a single offtake or for a set of offtakes.

Time indicators

David Dorchies — 2009-10-22T15:33:51Z

We define TD as the total period of time during which the demand discharge is non-zero and TEF as the total period of time during which the effective discharge is non-zero. We introduce the indicator IND4 = TEF/TD. It compares the duration of delivery of the effective volume with that of the demand volume. This indicator is dimensionless and can only be calculated for individual offtakes since it doesn't have any significance for all the offtakes taken together.

We also define two time lags: DT1 and DT2. DT1 is the time separating the start of the water demand and the start of the effective discharge. This time is positive if the effective discharge arrives after the demand discharge (Cf. figure 30). DT2 is the time lag between the centers of gravity of the demand hydrograph and the effective delivery hydrograph.

Figure 30

All these indicators are defined for each offtake. They can be calculated for any particular period of the simulation that the user wants to focus on.

Performance indicators

David Dorchies — 2009-10-22T15:33:48Z

Some performance indicators have been inserted with the aim of evaluating the efficiency of the discharge delivered at offtakes. They permit an integration of discharge information at offtakes, either for an unique offtake, or for all offtakes. There are two indicator types: volume indicators and time indicators.

The definition of these indicators is detailed in the theoretical guide. Volume indicators refer to 3 types of volumes:

- asked volume (VD), which is the targeted volume at offtakes,

- provided volume (VS) which is the real volume supplied at offtakes,
- effective volume (VEF) which is the real usable part of the provided volume.

The following colours are used to display the indicators (in RESIR):
- green, if the value is between 1 and 1.,5
- light green, if the value is superior to 1.5

- red, if the value is between 0.5 and 1
- light red, if the value is lower than 0.5

Remark: The validity of these indicators is poor when the storage of data on the result file is not done at each time step, because some discharge values will be missing (Cf. "Time parameters").