In the Net Discharge Head equation Hd = hd + hv + hp + hf, what does hd denote?

• A. Static discharge head
• B. Static suction head
• C. Height head
• D. Pressure head

Answer: (A)

hd is the static discharge head—the elevation-related energy on the discharge side. It represents the vertical lift the pump provides to move the fluid from the reference level up to the discharge point, independent of how fast the fluid is moving or what pressure exists at discharge. In the Net Discharge Head formula, this static component is added to the velocity head, pressure head, and friction head to give the total head at discharge. If the discharge point is higher than the pump, hd is positive; if it’s at the same level, hd is zero. The term for the analogous energy on the suction side is not part of hd.