Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p125
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 125/150)
Character Range: 1071491–1074696

applied:
              Where:
              uCO2 is the ratio between CO2 density and density of the exhaust gas
              cCO2,i is the instantaneous CO2 concentration in the exhaust gas, ppm
              qmew,i is the instantaneous exhaust mass flow, kg/s
              f is the data sampling rate, Hz
              n is the number of measurements
              Optionally, the CO2 mass may be calculated in accordance with paragraph 8.4.2.4. of Annex 4 by using a CO2 molar mass (MCO2) of 44.01 g/mol.
              3.2. Dilute measurement
              This paragraph applies, if CO2 is measured in the dilute exhaust gas.
              3.2.1. Measurement
              CO2 in the dilute exhaust gas emitted by the engine submitted for testing shall be measured with a non-dispersive infrared (NDIR) analyser in accordance with paragraph 9.3.2.3. and Appendix 2 to Annex 4. Dilution of the exhaust shall be done with filtered ambient air, synthetic air or nitrogen. The flow capacity of the full flow system shall be large enough to completely eliminate water condensation in the dilution and sampling systems.
              The measurement system shall meet the linearity requirements of paragraph 9.2. and Table 7 of Annex 4.
              The measurement system shall meet the requirements of paragraphs 9.3.1., 9.3.4. and 9.3.5. of Annex 4.
              3.2.2. Data evaluation
              The relevant data shall be recorded and stored in accordance with paragraph 7.6.6. of Annex 4.
              3.2.3. Calculation of cycle averaged emission
              If measured on a dry basis, the dry/wet correction according to paragraph 8.1. of Annex 4 shall be applied.
              For systems with constant mass flow (with heat exchanger), the mass of CO2 (g/test) shall be determined with the following equation:
              mCO2 = 0.001519 x cCO2 x med (in g/test)
              Where:
              cCO2  is the average background corrected CO2 concentration, ppm
              0.001519 is the ratio between CO2 density and density of air (u factor)
              med  is the total diluted exhaust mass over the cycle, kg
              For systems with flow compensation (without heat exchanger), the mass of CO2 (g/test) shall be determined by calculating the instantaneous mass emissions and integrating the instantaneous values over the cycle. Also, the background correction shall be applied directly to the instantaneous concentration values. The following equation shall be applied:
              Where:
              cCO2,e is the CO2 concentration measured in the diluted exhaust gas, ppm
              cCO2,d is the CO2 concentration measured in the dilution air, ppm
              0.001519 is the ratio between CO2 density and density of air (u factor)
              med,i is the instantaneous mass of the diluted exhaust gas, kg
              med is the total mass of diluted exhaust gas over the cycle, kg
              D is the dilution factor
              Optionally, the u factor may be calculated with equation 57 in paragraph 8.5.2.3.1. of Annex 4 by using a CO2 molar mass (MCO2) of 44.01 g/mol.
              CO2 background correction shall be applied in accordance