Total dynamic head (TDH) in feet is defined as the sum of static head, friction losses, and minor losses, with appropriate conversions between psi and feet when needed.

• A. static_head_ft + friction_loss_ft (converted) + minor_losses
• B. static_head_ft - friction_loss_ft - minor_losses
• C. static_head_ft * friction_loss_ft + minor_losses
• D. friction_loss_ft + minor_losses only

Answer: (A)

Total dynamic head in feet is the total energy the pump must supply to push water through the system. It’s found by adding three components: the static head (the elevation difference the water must overcome), friction losses (energy lost as water flows through pipes), and minor losses (additional losses from fittings, valves, bends, and other components). To combine them, express all of them in the same unit, typically feet of head. If any part is given in psi, convert to feet of head using about 2.31 feet of head per psi for water, then sum static head, friction losses, and minor losses. Subtracting losses or multiplying terms would misrepresent the actual head required, and using only losses ignores the elevation the pump must lift. The correct approach is to add all three components after proper conversion.