2. BRAKE PARTICLE EMISSIONS
TASK FORCE 2
Brake Dust Sampling and Measurement
Theodoros Grigoratos and TF2 Members
47th PMP IWG Meeting – Ispra (IT) –

3. TASK FORCE COMPOSITION
OEMs: AUDI; BMW; Ford; GM; Opel
Instrument and Brake Dyno Manufacturers: AVL; DEKATI; HORIBA; LINK Engineering; TSI
Brake Industry: Brembo; Federal Mogul; ITT Motion Technologies; TMD Friction
Research Institutes and Academia: Federal Institute for Materials Research and Testing (BAM); Japan Automobile Research Institute; TU Ilmenau; TU Ostrava
Other Organizations: California Air Resources Board; Joint Research Centre

4. NON-EXHAUST PARTICLE EMISSIONS BRAKE DUST SAMPLING AND MEASUREMENT
September 2017: A decision to merge Step 2 (Development of a suitable methodology for sampling brake wear particles) & 3 (Selection of the most suitable methods for brake wear particles’ measurement and characterization) in one Task was taken.
i. Why were the two steps merged in one?
Brake particle measurement and characterization techniques are closely related and largely depend on the selected sampling procedure. Critical parameters of the sampling procedure (geometry, flow rate, losses, background, etc.) have a large influence on the particles’ properties and therefore to the measurement and characterization of brake wear particles

5. BRAKE DUST SAMPLING AND MEASUREMENT
MAIN TASKS
Selection of the testing methodology (Concluded)
Comparison of existing systems/test rig configurations (Deadline: January 2018 – Concluded on-time)
Selection/definition of testing parameters (Deadline: March 2018 – Still on-going)
Validation of the selected configuration(s) & measurement methodologies (Deadline: To be defined depending on the progress)
Data processing method (Deadline: To be defined depending on the progress)

6. BRAKE DUST SAMPLING AND MEASUREMENT
SELECTION OF THE TESTING METHODOLOGY
Pin-on-disc
Brake dyno
Chassis dyno
Also, different on-road approaches have been employed by several researchers

7. BRAKE DUST SAMPLING AND MEASUREMENT
SELECTION OF THE TESTING METHODOLOGY
ii. Why it was decided to select the brake test rig approach?
Pin-on-disc systems are simpler compared to other options but they do not take into account the pad shape, the caliper design and aerodynamics
In brake dynos there are deviations from reality in terms of aerodynamics. Also its use restrict the range of technologies that could be used for particle emission reduction to the brake system level. However, it was selected as a compromise due to its simplicity and lack of a better alternative
Full chassis-dyno was rejected due to its complexity, lack related activities worldwide as well as limitations in distinguishing brake wear particles from particles from other sources (i.e. tyres)

8. BRAKE DUST SAMPLING AND MEASUREMENT
COMPARISON OF EXISTING TEST RIG CONFIGURATIONS
iii. What was the idea behind this task?
TF2 partners would present their sampling and measurement configurations with focus on the technical characteristics rather than actual wear results
This way TF2 would become familiar with existing configurations and then decide which ones are closer to meet the requirements of our work
Furthermore, improvements on existing configurations could be achieved through internal discussions on the technical details of the individual set-ups

9. BRAKE DUST SAMPLING AND MEASUREMENT
COMPARISON OF EXISTING TEST RIG CONFIGURATIONS
iv. What was the main outcome of this task?
10 partners presented their configurations in terms of their technical characteristics while in some cases actual wear results were also provided
Some of the configurations were designed for completely different purposes and therefore are not appropriate for the purposes of the current exercise
There is a great variation between the systems presented. Some set-ups are appropriate for PM measurements but not for PN and vice versa. Also, there is a wide variety in duct dimensions, enclosure geometry, etc. leading to completely different technical specifications

10. BRAKE DUST SAMPLING AND MEASUREMENT
COMPARISON OF EXISTING TEST RIG CONFIGURATIONS
Technical Specifications
JARI
TU Ilmenau
Ford
Horiba – Audi
Brembo
LINK
TU Ostrava GM
Inlet air flowrate
(Min – Max – Optimal)
Adjustable
30 – 300 m3/h. Optimal 60 m3/h
PM2.5-setup:
850 m³/h
(Min: 100 m³/h – Max: 1000m³/h)
Optimal air flowrate value set at 250 m³/h
430 – 3300 m3/h Optimal value set at 3300 m3/h
500 – 2500 m3/h Optimal value set at 1175 m3/h
250 – 2500 m3/h
Max m3/h
630 to 4900 m3/h.
Not optimized for PM sampling
Duct diameter and geometry
Straight line.
D = 84.9 mm
(or 100 mm)
Horizontal π shaped duct.
D = 160 mm
Vertical reverse U shaped duct .
D =150 mm
90° bend
CVS tunnel .
D = 300 mm
Vertical reverse U shaped duct.
D = 56 mm
Vertical reverse π shaped duct.
D adjustable 100 – 250 mm
“C”-shaped duct.
D =300 mm
Square.
D =356mm

11. BRAKE DUST SAMPLING AND MEASUREMENT
SELECTION/DEFINITION OF TESTING PARAMETERS
MAIN STEPS
Define the scope based on the mandate and what is feasible to achieve with the current state of experience in the TF2 (Concluded)
Structure the work in different thematic topics (Concluded)
Define individual groups within the TF2 to deal with each thematic topic (On-going – to be concluded in June)
Start collecting experimental data within the TF2 (June and onwards)

12. BRAKE DUST SAMPLING AND MEASUREMENT
SELECTION/DEFINITION OF TESTING PARAMETERS
Define the scope based on the mandate and what is feasible to achieve with the current state of experience in the TF2 (Concluded)
v. What are the main elements of the scope?
There is a consensus that PM10, PM2.5 and PN concentrations could be measured concurrently. However, different measurement principles shall be applied. PM and PN size distributions are desirable but will remain out of the main scope due to technical complexity
The methodology should try to simulate real world conditions instead of characterizing particles at their generation point. The aim is creating comparable and harmonized measurement systems for R&D and scientific purposes

13. BRAKE DUST SAMPLING AND MEASUREMENT
SELECTION/DEFINITION OF TESTING PARAMETERS
Structure the work in different thematic topics (Concluded)
Define individual groups within the TF2 to deal with each thematic topic (On-going – to be concluded in June)
vi. What is the current status regarding these items?
The work has been structured in 9 Chapters (document will be presented separately) based on the needs identified at the discussion for the definition of the scope
Smaller groups have been nominated as “responsible” for drafting individual chapters (see document). Feedback from all TF2 partners will be added after the first draft of the chapters

14. BRAKE DUST SAMPLING AND MEASUREMENT
SELECTION/DEFINITION OF TESTING PARAMETERS
Start collecting experimental data within the TF2 (June and onwards)
Data already exist from previous projects (already presented in 37th – 45th PMP Meetings)
TF2 members are involved in many on-going projects and more data will come from there in the near future
Based on this data the TF2 will define all necessary testing parameters and will come up with a minimum set of requirements for the sampling set-up and the necessary instrumentation

15. BRAKE DUST SAMPLING AND MEASUREMENT
VALIDATION OF THE SELECTED CONFIGURATION(S)
vii. What is the goal of this particular task?
TF2 will test existing configurations which comply with the requirements set by the group for the repeatability of their results
A round robin will take place to verify the reproducibility of the testing procedure among the different compliant configurations
This step will ensure that the work done in the previous steps makes sense

16. Any questions?
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