Enter the elevation head, friction head loss, and pressure head into the calculator to determine the total dynamic head (TDH).

TDH – Total Dynamic Head – Formula

The following formula is used to calculate a total dynamic head: 

TDH = PH + FLH + EH
  • Where TDH is the total dynamic head (ft)
  • PH is the pressure head (ft)
  • FLH is the friction head loss (ft)
  • EH is the elevation head

To calculate the total dynamic head, sum the pressure head, friction head loss, and elevation head.

TDH Definition

TDH, short for the total dynamic head, is the total head loss that a pump must overcome in order to move and pump water.

The total head loss has three components:

Elevation Head: The amount of head/pressure the pump needs to overcome due to the elevation of the system

Pressure Head: The amount of head the pump needs to overcome due to pressure.

Friction Loss Head: The head is created due to friction of the water flow in the pipes.

Example Problem

How to calculate the total dynamic head?

First, determine the elevation head. For this example, the pump must overcome 100 ft of elevation.

Next, determine the pressure head. In this case, the pressure head is found to be 12ft.

Next, determine the friction loss head. The total friction loss is an equivalent head of 10ft.

Finally, calculate the TDH using the formula above:

TDH = PH + FLH + EH

TDH = 100 + 12 + 10

TDH = 122 ft of total head

FAQ

What is the importance of calculating Total Dynamic Head (TDH) in a pumping system?
Calculating TDH is crucial for selecting the right pump for a specific application. It ensures that the pump has enough power to move water through the system’s entire elevation, overcome pressure losses, and handle friction losses in the pipes, providing efficient and effective operation.

How can elevation affect the Total Dynamic Head in a system?
Elevation affects TDH by adding to the height that the pump needs to lift the fluid. Higher elevations require the pump to work harder to overcome gravitational forces, increasing the TDH. This is especially significant in systems where fluids are pumped from lower to higher levels.

Can the Total Dynamic Head change over time, and what factors contribute to such changes?
Yes, the TDH can change over time due to several factors, including pipe wear leading to increased friction losses, changes in system elevation due to construction or modifications, and variations in pressure requirements based on system demand. Regular system evaluations are necessary to ensure optimal pump performance.