Evaluation on Maximum CO2-Delta in 2-Tests-Approach WLTP-DTP-LabProcICE-238 Evaluation on Maximum CO2-Delta in 2-Tests-Approach Simulation example with wide spread family data A. Feucht Audi AG 28.6.2013

Comparison of simulation values against interpolation with 2-test-approach Family of A4 sedan (bc), A4 hatchback, A5 Coupe, A5 Cabrio, A4 allroad (wc) Same 4-cyl. gasoline engine and 7-gear-aut. transmission, 4WD, same n/v-ratio TML: 1674kg; TMH 1948 kg Difference in cd*A: 0.1526 m2 Rolling resistance: min: 6,5 kg/t; max: 10,5 kg/t Weight RR Aero ⊿CO2 total =32.8g ① ③ ② ④ ⑧ ⑤ ⑦ ⑥ Worst Best 9 Annette Feucht, I/EG-341, 20130521_max_Delta_2-tests-approach, 21. Mai 2013

Results Overall deviation between the simulation test and the interpolated values is less than 0.7 g/km for the standard gasoline engine with an interpolation range of 32.8 g/km Intermediate range „individual“ vehicle, which is most likely to be configured by the customer, shows even less deviation in all phases. Annette Feucht, I/EG-341, 20130521_max_Delta_2-tests-approach, 21. Mai 2013

Conclusion Interpolation between measured best- and worst-case-vehicle regarding to rolling resistance coefficient, aerodynamic drag and weight is at least as accurate as measuring more configurations for interpolation. This is because in a CO2-measurement of an individual set of parameters the tolerances and measurement insecurities add up (RLD + dyno setting + WLTP measurement) and with a reasonable number of measurements the overall-tolerance is at least 1 g/km rather 2-3 g/km (0,1 l/100km). It is demonstrated that the 2-test-interpolation method also works for best-case to worst-case differences of over 30g/km if only mass, rolling resistance and aerodynamics are changed in a car. Annette Feucht, I/EG-341, 20130521_max_Delta_2-tests-approach, 21. Mai 2013