Control valves (a fortiori when operating under conditions of high pressure drop) can contribute significantly to industrial & process plant noise, namely due to aerodynamic noise generation depending on valve data & process data, main parameters being as follows:

  • Valve inlet absolute pressure
  • Valve outlet absolute pressure
  • Liquid pressure recovery factor of a valve with or without attached fittings
  • Pressure differential ratio factor of a control valve with or without attached fittings at choked flow
  • Valve style modifier
  • (Required) Flow coefficient
  • Acoustic power ratio or Valve correction factor for acoustical efficiency
  • Molecular mass of flowing fluid
  • Inlet absolute temperature
  • Density of fluid at inlet
  • Specific heat ratio
  • Mass flow rate
  • Strouhal number
  • Outlet absolute temperature
  • Density of fluid at outlet
  • Speed of sound at downstream conditions
  • Valve outlet diameter
  • Internal downstream pipe diameter
  • Contraction coefficient for valve outlet or expander inlet

When valve style modifier is not an available explicit input data, additional parameters must be accounted

  • Area of a single flow passage 
  • Wetted perimeter of a single flow passage
  • Number of independent and identical flow passages in valve trim

When flow indicators are not available explicit input data, additional parameters must be accounted

  • Liquid pressure recovery factor of a valve without attached fittings
  • Upstream inside pipe diameter

Links to learn more about control valves noise calculation