1. What is Total Dynamic Head (TDH)?

Total Dynamic Head (TDH) is the total equivalent height that a fluid is to be pumped, taking into account friction losses in the pipe. It's a crucial parameter for selecting the right pump for a given application.

2. How Does the Calculator Work?

The calculator uses the TDH equation:

Where:

• \( Static\ Head \) — Vertical distance from water surface to discharge point (ft)
• \( Friction\ Loss \) — Head loss due to friction in pipes and fittings (ft)
• \( Pressure\ Head \) — Additional pressure required at discharge (converted to ft)

Explanation: TDH represents the total resistance the pump must overcome, including elevation changes, pipe friction, and any required discharge pressure.

3. Importance of TDH Calculation

Details: Accurate TDH calculation is essential for proper pump selection. An undersized pump won't deliver required flow, while an oversized pump wastes energy and may cause operational issues.

4. Using the Calculator

Tips: Enter static head (vertical lift), friction loss (from pipe calculations), and any additional pressure head required. All values must be in feet (convert psi to feet by multiplying by 2.31).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between static head and dynamic head?
A: Static head is the vertical distance only, while dynamic head includes friction losses and pressure requirements.

Q2: How do I calculate friction loss?
A: Friction loss depends on pipe size, length, material, flow rate, and number of fittings. Use hydraulic tables or software.

Q3: When is pressure head needed?
A: When the system requires pressure at discharge (e.g., sprinkler systems, pressure tanks).

Q4: How does TDH affect pump selection?
A: The pump curve must show adequate flow rate at your calculated TDH. Select a pump where your operating point is near its best efficiency point.

Q5: What units should I use?
A: This calculator uses feet. For metric, convert meters to feet (1 m = 3.28 ft) or modify the formula to use meters.