EN
16.1.2023
Official Journal of the European Union
L 14/143
(32)
Where: qmaw,i
is the instantaneous intake air mass flow rate, kg/s
A/Fst
is the stoichiometric air to fuel ratio, kg/kg
λi
is the instantaneous excess air ratio
cCO2d
is the dry CO2 concentration, per cent
cCOd
is the dry CO concentration, ppm
cHCw
is the wet HC concentration, ppm
Air flow meter and analyzers shall meet the linearity requirements of paragraph 9.2., and the total system shall meet the linearity requirements for the exhaust gas flow of paragraph 9.2.
If an air to fuel ratio measurement equipment such as a zirconia type sensor is used for the measurement of the excess air ratio, it shall meet the specifications of paragraph 9.3.2.7.
8.4.1.7.
Carbon balance method This involves exhaust mass calculation from the fuel flow and the gaseous exhaust components that include carbon.
The calculation of the instantaneous exhaust gas mass flow is as follows:
(33)
With kc= (cCO2d – cCO2d,a) x 0,5441 + cCOd/18522 + cHCw/17355 (34) And kfd = - 0,055586 x wALF + 0,0080021 x wDEL + 0,0070046 x wEPS (35) Where: qmf,i
is the instantaneous fuel mass flow rate, kg/s
Ha
is the intake air humidity, g water per kg dry air
wBET
is the carbon content of the fuel, per cent mass
wALF
is the hydrogen content of the fuel, per cent mass
wDEL
is the nitrogen content of the fuel, per cent mass
wEPS
is the oxygen content of the fuel, per cent mass
cCO2d
is the dry CO2 concentration, per cent
cCO2d,a
is the dry CO2 concentration of the intake air, per cent