Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:13:p17
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 13 (pt 17/56)
Character Range: 341640–344672

ratio, kg/kg
                  i 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

              cCOd is the dry CO concentration, ppm

 cHCw is the wet HC concentration, ppm
8.4.2. Determination of the gaseous components
8.4.2.1. Introduction
 The gaseous components in the raw exhaust gas emitted by the engine submitted for testing shall be measured with the measurement and sampling systems described in paragraph 9.3. and Appendix 2 to this annex. The data evaluation is described in paragraph 8.4.2.2.
 Two calculation procedures are described in paragraphs 8.4.2.3. and 8.4.2.4., which are equivalent for the reference fuel of Annex 5. The procedure in paragraph 8.4.2.3. is more straightforward, since it uses tabulated u values for the ratio between component and exhaust gas density. The procedure in paragraph 8.4.2.4. is more accurate for fuel qualities that deviate from the specifications in Annex 5, but requires elementary analysis of the fuel composition.
8.4.2.2. Data evaluation
 The emission relevant data shall be recorded and stored in accordance with paragraph 7.6.6.
 For calculation of the mass emission of the gaseous components, the traces of the recorded concentrations and the trace of the exhaust gas mass flow rate shall be time aligned by the transformation time as defined in paragraph 3.1. Therefore, the response time of the exhaust gas mass flow system and each gaseous emissions analyzer shall be determined