Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:16:p30
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 16 (pt 30/108)
Character Range: 969090–972135

dynamic tyre radius of the vehicle with which the running resistance was determined, m;
                   1.02 is an approximate coefficient compensating for drivetrain losses.
              8.2.4.1.2. The determined f0, f1, f2 values shall not be used for a chassis dynamometer setting or any emission or range testing. They shall be used only in the following cases:
                  (a) Determination of downscaling, paragraph 8. of Annex B1;
                  (b) Determination of gearshift points, Annex B2;
                  (c) Interpolation of CO2 and fuel consumption, paragraph 3.2.3 of Annex B7;
                  (d) Calculation of results of electric and hybrid-electric vehicles, paragraph 4. of Annex B8.
              8.2.4.2. Once the chassis dynamometer has been set within the specified tolerances, a vehicle coastdown procedure shall be performed on the chassis dynamometer as outlined in paragraph 4.3.1.3. of this annex. The coastdown times shall be recorded.
              8.2.4.3.  The road load Fj at reference speed vj, N, shall be determined using the following equation:
              where:
               Fj is the road load at reference speed vj, N;
              TM is the test mass of the vehicle, kg;
                  mr is the equivalent effective mass of rotating components according to paragraph 2.5.1. of this annex, kg;
              ∆v = 5 km/h
              ∆tj is the coastdown time corresponding to speed vj, s.
              8.2.4.4. The coefficients f0, f1 and f2 in the road load equation shall be calculated with a least squares regression analysis over the reference speed range.
Annex B5

Test equipment and calibrations
              1. Test bench specifications and settings
              1.1. Cooling fan specifications
              1.1.1. A variable speed current of air shall be blown towards the vehicle. The set point of the linear velocity of the air at the blower outlet shall be equal to the corresponding roller speed above roller speeds of 5 km/h. The linear velocity of the air at the blower outlet shall be within ±5 km/h or ±10 per cent of the corresponding roller speed, whichever is greater.
              1.1.2. The above-mentioned air velocity shall be determined as an averaged value of a number of measuring points that:
                  (a) For fans with rectangular outlets, are located at the centre of each rectangle dividing the whole of the fan outlet into 9 areas (dividing both horizontal and vertical sides of the fan outlet into 3 equal parts). The centre area shall not be measured (as shown in Figure A5/1);
Figure A5/1
Fan with rectangular outlet
                  (b) For fans with circular outlets, the outlet shall be divided into 8 equal sectors by vertical, horizontal and 45° lines. The measurement points shall lie on the radial centre line of each sector (22.5°) at two-thirds of the outlet radius (as shown in Figure A5/2).
Figure A5/2
Fan with circular outlet
              These measurements shall be made with no vehicle or other obstruction in