Document ID: chunk:federal_register_of_legislation:F2023C00229:reg:9:p6
Version: federal_register_of_legislation:F2023C00229
Segment Type: reg
Provision Reference: reg 9 (pt 6/71)
Character Range: 223041–226350

calculated as follows:

              and:
               where,

                      ER, ES, ET, EU = specific NOx emission of the enveloping modes calculated in accordance with Section 4.6.1.
              MR, MS, MT, MU = engine torque of the enveloping modes

        Figure 4

        Interpolation of NOx control point

4.6.3.                        Comparison of NOx emission values

              The measured specific NOx emission of the control point Z (NOx,Z) is compared to the interpolated value (EZ) as follows:

5.                                 CALCULATION OF THE PARTICULATE EMISSION

5.1.                            Data evaluation

              For the evaluation of the particulates, the total sample masses (MSAM,i) through the filters shall be recorded   for each mode.

              The filters shall be returned to the weighing chamber and conditioned for at least one hour, but not more than 80 hours, and then weighed. The gross weight of the filters shall be recorded and the tare weight (see Section 1 of this Appendix) subtracted. The particulate mass Mf is the sum of the particulate masses collected on the primary and back-up filters.

              If background correction is to be applied, the dilution air mass (MDIL) through the filters and the particulate mass (Md) shall be recorded. If more than one measurement was made, the quotient Md/MDIL must be calculated for each single measurement and the values averaged.

5.2.                            Partial flow dilution system

              The final reported test results of the particulate emission shall be determined through the following steps. Since various types of dilution rate control may be used, different calculation methods for GEDFW apply. All calculations shall be based upon the average values of the individual modes during the sampling period.

5.2.1.                        Isokinetic systems

              where r corresponds to the ratio of the cross-sectional areas of the isokinetic probe and the exhaust pipe:

5.2.2.                        Systems with measurement of CO2 or NOx concentration

              where:

              concE = wet concentration of the tracer gas in the raw exhaust concD = wet concentration of the tracer gas in the diluted exhaust concA = wet concentration of the tracer gas in the dilution air
              Concentrations measured on a dry basis shall be converted to a wet basis according to Section 4.2 of this Appendix.

5.2.3.                        Systems with CO2 measurement and carbon balance method (1)

              where:

              CO2D = CO2 concentration of the diluted exhaust CO2A = CO2 concentration of the dilution air (concentrations in vol % on wet basis)
              This equation is based upon the carbon balance assumption (carbon atoms supplied to the engine are emitted as CO2) and determined through the following steps:

              and

5.2.4.                        Systems with flow measurement

    (1) The value is only valid for the reference fuel specified in Annex IV.

5.3.                            Full flow dilution system

              The reported test results of the particulate emission shall be determined through the following steps. All calculations shall be based upon the