Dynamic total head is the sum of which dynamic components?

• A. Flow rate and head
• B. Dynamic suction lift and dynamic discharge head
• C. Total head and flow
• D. Suction head and discharge head

Answer: (B)

Dynamic total head is the energy per unit weight the pump must provide to move water from the source to the discharge, including what happens on both sides of the pump. It is the sum of the dynamic suction lift and the dynamic discharge head. The dynamic suction lift accounts for the energy needed to raise water in the suction line and overcome the velocity there; the dynamic discharge head accounts for the energy needed to push water through the discharge line, including its velocity. Adding these two dynamic components gives the total dynamic head the pump must overcome to achieve the desired flow. The other options mix in flow rate or static terms, which don’t represent the dynamic energy the pump must supply on both sides.