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Non-exhaust emissions in general and brake particle emissions in particular have become very relevant during the last years. Even if many investigations and efforts are under progress, no common test standards exist so far. Many mechanisms and possible impacts are not fully understood either. Hence, the authors continued their investigations by using an already refined and proved test setup, which is the base for further characterizations and enhancements. The presented studies include the characterization of three different friction couples (using the same brake system) for two different test cycles (namely a modified AK Master and a WLTP) in terms of particle number concentration. Additionally, the major differences of the modified AK Master and the WLTP are investigated and analyzed. Finally, results of particle mass characterizations introduced. A brief summary and some conclusions are presented in the final chapter.

Brake Particle Emission (BPE) is gaining considerable importance for the friction brake and automotive industry. So far no common approach or legislation for BPE characterization exists although many activities in this field have been started during the last years. Taking this into account, the authors carried out a joint measurement campaign to investigate a new approach regarding the sampling location using a brake dynamometer. During preliminary investigations the influence of the cooling air quality has been examined and a sampling point position validation has been carried out. At first the stabilization behavior for repeated test cycles and variations of volumetric air flow rates are analyzed. As a next step the role of volatile particle emissions is determined. Subsequently, the influence of load history and friction power is studied. Finally results in terms of the role of high temperature applications are presented.

The variety of increasingly complex powertrains including Plug-In Hybrid Electric Vehicles (PHEVs) is associated with a number of challenges to measure exhaust gas emissions: Although the conventional constant volume sampling (CVS) and exhaust gas measurement systems remain a high precision emission measurement concept new questions occur that need to be answered, such as mass transport, catalyst cooling during ICE-off and emission measurement accuracy. Mass transport of exhaust emissions from the transfer tube into the dilution tunnel during engine-off complicates phase assignment. This includes the investigation of the physical processes that are diffusion on basis of concentration differences, extraction due to the CVS underpressure and convection because of density diversities. Catalyst cooling will be investigated using a temperature sensor positioned at the oxy catalyst of a Diesel-PHEV.