KROHNE Summit 8800 Vol 2 - Manual (Page 186)

186 www.krohne.com 08/2013 - MA SUMMIT 8800 Vol2 R02 en
SUMMIT 8800 APPENDIX 2: GAS CALCULATIONS 17
s
b c N
q = q
ρ
ρ
1
×
Equation 27 Normal volume flow rate
qn Normal volume flow [Nm³/h]
qbc Corrected line volume flow [m³/h]
ρ1 Line Density [kg/m3]
ρs Base Density [kg/m3]
17 .5 Calculate base and line density
The flow computer calculates the base compressibility, and base density based on the gas com-
position in-use according to the AGA-8 standard.
The line density is calculated according the AGA-8 standard based on the gas composition in-
use.
17 .6 Calculation for mass flow rate
1000
*
1
ρ
b c
m
q
q
=
Equation 28 Mass flow rate
qm Gross volume mass flow rate [t/h]
qbc Corrected line volume flow [m³/h]
ρ1 Line density [kg/m3]
17 .7 Calculation for energy flow rate
cv q q
N E
× =
Equation 29 Energy flow rate
qE Energy flow rate [MJ/h]
qn Normal volume flow [Nm³/h]
cv Caloric value of the gas [MJ/Nm3]
17 .8 Calculate heating value
The flow computer calculates the calorific value according to the ISO-6976 standard, based on
the gas composition in-use.
17 .9 Integrate flow rates for totalisation
All rates of flow are integrated to form cumulative totals.