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Head loss coefficient of a partially open butterfly valve
Default

Input data

Diameter

Opening angle (°)

Output data

k of type A

kQ of type A

k of type B

kQ of type B

k of type C

kQ of type C

Description

Find the head loss coefficients for partially open butterfly valves.

Given the diameter and the opening angle of a butterfly valve, calculates the head loss coefficients corresponding to three different types of valves, for the expressions:

  • For k applicable to:
    hf=k⋅U22⋅g hf = \frac{k \cdot U^2}{2\cdot g}
  • For kQk_Q applicable to:
    hf=kQ⋅Q2 ℎf = k_Q\cdot Q^2

Types of opening valves

References

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