scope:

This part of ISO 6358 specifies a method that uses a simplenumerical technique to estimate without measurements the overallflow-rate characteristics of a system of components and piping withknown flow-rate characteristics. The formulae used in this part ofISO 6358 describe the behaviour of a compressible fluid flowthrough a component for both subsonic and choked flows. NOTE Theconductance of a tube, silencer or filter is influenced by theupstream pressure, so the values of C and b are only valid for theupstream pressure at which they are determined. This part of ISO6358 also provides methods to obtain equivalent flow-ratecharacteristics for components whose flow-rate characteristicsdiffer from those defined in the ISO 6358 series.