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Is there any conversion factor between Nm3/hr anf m3/hr?
I am confused because gas flowrate are measured in KNm3/hr while liquified gas flowrate are measured in m3/hr.
To convert Nm3/hr to M3/hr, use Nm3/hr*(Pnormal/Pactual)*(Tactual/Tnormal)
Where normal conditions are 1 atm and 0°C
23/05/2011 A: keith bowers, B and B Consulting, kebowers47@gmail.com
This issue of 'conversion factors' is usually well covered in the first course in Chemical Engineering curriculums and similar fields of physical science.
Nm3 means Normal--i.e.'standard temperature and pressure conditions. 'Actual m3' is real physical volume at the flowing conditions.
'Most' liquid flow meters are calibrated to indicate Normal(standard) volume units by incorporating actual flowing pressure and temperature into the 'meter factor' used to calculate the 'calibrated flow rate' from the output signal of the flow measuring element (orifice delta p for example).
In your example, Nm3 is fully specified and 'known.' m3, as given, is also 'known' as actual volume AT THE MEASURED CONDITIONS, unless corrected to 'standard conditions', when then Nm3 is appropriate
23/05/2011 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
Gases are referenced to a standard set of atmospheric conditions. Referring liquids that way is not needed. No conversion. When gas is liquified, it can be treated as a liquid. Since LNG is not pumped from a vessel open to the atmosphere, atmospheric conditions are not relevent even in an NPSH calculation, for example.