Storage at End of Time Interval of Reservoir Calculator

Storage at End of Time Interval Formula:

\[ S_2 = S_1 + \left( \frac{I_1 + I_2}{2} \right) \times \Delta t - \left( \frac{Q_1 + Q_2}{2} \right) \times \Delta t \]

Storage at the Beginning of Time Interval:

m³

Inflow at the Beginning of Time Interval:

m³/s

Inflow at the End of Time Interval:

m³/s

Outflow at the Beginning of Time Interval:

m³/s

Outflow at the End of Time Interval:

m³/s

Time Interval:

Storage at the End of Time Interval:

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1. What is Storage at End of Time Interval?

The Storage at End of Time Interval represents the amount of water stored in reservoirs within a hydrological system at the end of a specified time period. It is calculated based on initial storage, inflow rates, outflow rates, and the time interval.

2. How Does the Calculator Work?

The calculator uses the reservoir storage equation:

\[ S_2 = S_1 + \left( \frac{I_1 + I_2}{2} \right) \times \Delta t - \left( \frac{Q_1 + Q_2}{2} \right) \times \Delta t \]

Where:

\( S_2 \) — Storage at the End of Time Interval (m³)
\( S_1 \) — Storage at the Beginning of Time Interval (m³)
\( I_1 \) — Inflow at the Beginning of Time Interval (m³/s)
\( I_2 \) — Inflow at the End of Time Interval (m³/s)
\( Q_1 \) — Outflow at the Beginning of Time Interval (m³/s)
\( Q_2 \) — Outflow at the End of Time Interval (m³/s)
\( \Delta t \) — Time Interval (s)

Explanation: The equation calculates the final storage by adding the average inflow and subtracting the average outflow over the time interval from the initial storage.

3. Importance of Reservoir Storage Calculation

Details: Accurate reservoir storage calculation is crucial for water resource management, flood control, irrigation planning, and hydroelectric power generation. It helps in understanding water availability and making informed decisions about water allocation.

4. Using the Calculator

Tips: Enter all values in appropriate units (storage in m³, flow rates in m³/s, time in seconds). All values must be non-negative, and time interval must be greater than zero for valid calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why use average inflow and outflow rates?
A: Using average rates provides a more accurate estimation of storage change over time, especially when inflow and outflow rates are not constant.

Q2: What are typical time intervals used?
A: Time intervals can vary from minutes to days depending on the application - shorter for flood forecasting, longer for reservoir management.

Q3: How accurate is this calculation method?
A: The method provides good accuracy for most practical purposes, though extremely variable flow conditions may require more sophisticated modeling.

Q4: Can this be used for any reservoir type?
A: Yes, the equation applies to all reservoir types including natural lakes, artificial reservoirs, and storage tanks.

Q5: What if outflow exceeds inflow?
A: When outflow exceeds inflow, the storage decreases over time, which is common during drought conditions or planned water releases.