How Do I Size a Surge Drum?

Modern engineering has provided us with more convenient, efficient living. Maintaining a regular water supply depends on a complex system of storage and distribution of which surge drums are a part. Surge drums handle sudden, significant inflows our outflows of pressure and accommodate for the corresponding changes in pressure and volume. Without them, aqueduct tanks would cease to function. Sizing surge drums is governed by a specific formula: Size = Starting Level + (inflow - outflow) * t / tank volume.

Instructions

1. Determine the starting level by reading the meter on the outside of the drum, which indicates the height of the drum contents.

2. Subtract outflow from inflow. Outflow refers to the liquid leaving the tank, while inflow refers to the incoming liquid. Use the formula P = p * v, where v is the volume of incoming (or outgoing) liquid and v is its pressure. Outflow, of course, will have a negative value.

3. Multiply the result in Step 2 by the time interval.

4. Divide the result in Step 3 by the volume of the tank.

5. Calculate the log of the result of Step 4 and add it to the initial level.

References

• Civil Engineering: Hydraulics; Bruce Larock; 2004