EN
L 14/148
Official Journal of the European Union
16.1.2023
The total mass of equivalent diluted exhaust gas mass over the cycle shall be determined as follows:
medf = (46) qmedf,i = qmew,i x rd,i
(47)
rd,i = (48) Where:
8.5.
qmedf,i
is the instantaneous equivalent diluted exhaust mass flow rate, kg/s
qmew,i
is the instantaneous exhaust mass flow rate, kg/s
rd,i
is the instantaneous dilution ratio
qmdew,i
is the instantaneous diluted exhaust mass flow rate, kg/s
qmdw,i
is the instantaneous diluent mass flow rate, kg/s
f
is the data sampling rate, Hz
n
is the number of measurements
Full flow dilution measurement (CVS) The concentration signals, either by integration over the cycle or by bag sampling, of the gaseous components shall be used for the calculation of the mass emissions by multiplication with the diluted exhaust mass flow rate.
The exhaust mass flow rate shall be measured with a constant volume sampling (CVS) system, which may use a positive displacement pump (PDP), a critical flow venturi (CFV) or a subsonic venturi (SSV) with or without flow compensation.
For bag sampling and particulate sampling, a proportional sample shall be taken from the diluted exhaust gas of the CVS system.
For a system without flow compensation, the ratio of sample flow to CVS flow shall not vary by more than ±2.5 per cent from the set point of the test.
For a system with flow compensation, each individual flow rate shall be constant within ±2.5 per cent of its respective target flow rate.
The complete test set up is schematically shown in Figure 7.