Abstract
The work presented on this paper is part of a larger activity that the California Air Resources Board embarked on to update brake emissions factors. To pursue such updates using laboratory testing, brake dynamometers need to provide speeds and temperatures that replicate, within reason, those for in-use vehicles on the road. To characterize the thermal regimes, the brake cycle derived from Worldwide Harmonised Light Vehicles Test Procedure (WLTP) was used as the test cycle on six vehicles fully instrumented, while driving on a closed-course proving ground. The use of the WLTP provides a clear reference to the initiatives from the Particle Measurement Programme (PMP), and allows future comparisons to driving cycles from California. This paper provides an overview of the temperature regimes on the friction couple on both axles for six different vehicles. In addition, this study implements a heating and cooling matrix as well as coast downs for total vehicle resistance. These additional measurements along with the WLTP-Brake track tested measurements offer the necessary inputs in building a brake temperature prediction model, account for occasional aggressive driving conditions, and provide the vehicle brake decelerations corrected for vehicle innate losses.