1. What is Total Dynamic Head?

Total Dynamic Head (TDH) is the total equivalent height that a fluid is to be pumped, taking into account both the static head (vertical lift) and friction losses in the system. It's a crucial parameter in pump system design and selection.

2. How Does the Calculator Work?

The calculator uses the fundamental TDH equation:

Where:

• \( Static\ Head \) — Vertical distance from water surface to discharge point (ft)
• \( Friction\ Loss \) — Pressure loss due to pipe friction (ft)

Explanation: The equation accounts for both the physical lift required and the energy lost due to friction in pipes and fittings.

3. Importance of TDH Calculation

Details: Accurate TDH calculation is essential for proper pump selection, ensuring the pump can overcome both elevation changes and system resistance to deliver the required flow rate.

4. Using the Calculator

Tips: Enter static head (vertical distance) and friction loss (from pipe friction calculations) in feet. Both values must be non-negative.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between static head and dynamic head?
A: Static head is just the vertical lift, while dynamic head includes both static head and friction losses.

Q2: How do I determine friction loss?
A: Friction loss can be calculated using the Hazen-Williams equation or Darcy-Weisbach equation based on pipe size, material, flow rate, and length.

Q3: Why is TDH important for pump selection?
A: Pumps are rated for specific flow rates at specific TDH values. Selecting a pump requires matching your system's TDH to the pump's performance curve.

Q4: Does TDH change with flow rate?
A: Static head remains constant, but friction loss increases with flow rate, so TDH increases as flow rate increases.

Q5: What units should be used for TDH?
A: TDH is typically expressed in feet (US) or meters (metric) of fluid column. This calculator uses feet.