Head loss coefficient in orifices and strainers

Input data

Area

Discharge coefficient

Output data

kQ

Description

The pressure loss coefficient in orifices and strainers is calculated based on the orifice area and the discharge coefficient. This coefficient is crucial for determining head loss in hydraulic systems with restricted openings.

The fundamental equation used in the calculation is:

hf=kQQ2h_f = k_Q \cdot Q^2

where:

  • hfh_f is the head loss (m)
  • kQk_Q is the pressure loss coefficient
  • QQ is the flow rate (m³/s)

The equation used to calculate kQk_Q is:

kQ=1(CdA)212gk_Q = \frac{1}{(C_d \cdot A)^2} \cdot \frac{1}{2g}

where:

  • AA is the orifice area (m²)
  • CdC_d is the discharge coefficient
  • gg is the gravitational acceleration (m/s²)

Input and Output Parameters

Inputs

Parameter
Standard Units
Description
Area (AA)
Orifice opening area
Discharge coefficient (CdC_d)
-
Flow efficiency factor

Output

Parameter
Standard Units
Description
kQk_Q
-
Pressure loss coefficient