Input data

Diameter (D) or height (H)

Opening ratio

Output data

k for knife gate valve

kQ for knife gate valve

k for gate valve

kQ for gate valve

Description

Find the head loss coefficients for partially open gate and knife gate valves.

Given the diameter and the opening relation of a gate valve, or the side and the opening relation of a knife gate valve, calculates the head loss coefficients, for the expressions hf = k.U²/2g and ℎf = kQ.Q².

For k applicable to: $hf = \frac{k \cdot U^2}{2\cdot g}$
For $k_Q$ applicable to: $ℎf = k_Q\cdot Q^2$

Gate valve

Description

Find the head loss coefficients for partially open gate and knife gate valves.

For k applicable to: $hf = \frac{k \cdot U^2}{2\cdot g}$
For $k_Q$ applicable to: $ℎf = k_Q\cdot Q^2$

Gate valve

References

Miller, Donald S. Internal flow systems. BHRA Fluid Engineers, 1978.