180 likes | 310 Views
Mobile Source Operations Division Information Session By Vehicle Emissions Testing Section September 6, 2012. Outline. Why emission testing? Who are we? What do we produce ? Why do we test vehicles? Who are our clients? How do we test vehicles? What are we planning for the future?.
E N D
Mobile Source Operations DivisionInformation SessionBy Vehicle Emissions Testing SectionSeptember 6, 2012
Outline • Why emission testing? • Who are we? • What do we produce? • Why do we test vehicles? • Who are our clients? • How do we test vehicles? • What are we planning for the future?
Vehicle Emissions Testing Section(VETS) • Mission: To generate reliable data to support the ARB to control air contaminants and greenhouse gases • VETS is responsible for testing LDVs for gaseous and particulate emission of regulated and unregulated pollutants. • VETS operates two of ARB’s 7 mobile source test cells (cells 2&3) • VETS is comprised of ARE, APS and Automotive Emission Test Specialist (AETS)
What Do We Produce? • We produce exhaust emissions data by testing LDVs on chassis dynamometer (dyno), and measuring pollutants in the exhaust • We operate direct reading analyzers for the following pollutants: • Total HC / Methane / CO / CO2 / NO / NOx • Real time particle number (PN) • We can also collect discrete exhaust samples for subsequent analysis by MLD, including: • Particulate Matter (PM) – Teflon filters • HC speciation – Tedlar bags • Alcohol and Carbonyl – impinger and DNPH cartridges • N2O – Tedlar bags • PM speciation – Teflon and quartz filters • We produce 500-600 tests a year • emission testing? • Types of tests we use
Why Do We Test Vehicles? • Verify compliance with emissions standards • Support emissions factors development • Support emissions research • Evaluate a vehicle’s emissions control system • Evaluate fuels and new control technology • Support development of new regulations • Evaluate effectiveness of existing programs
Who Are Our Clients? • mission testing? • PTSD – Vehicle Surveillance Program supporting EMFAC and AQ model • MSOD – In-Use Vehicle Compliance, New Vehicle Certification, After-Market Parts Program, cross-check • RD – ARB research programs (LDV toxicity project) • BAR, SCAQMD and Academia - Collaborative research projects with UC Davis, Carnegie Melon University, CE-CERT • AIGER – Testing method evaluation (AIGER: Automobile Industry/Government Emissions Research)
Filters Cooling Fan Gas Analyzer Bench Dyno Controller Test Cell Setup PM Sampler Dilution Air Blower Dilute Exhaust Driver’s Aid Bag Rack Engine Cat Dilution Tunnel CVS DYNO Emissions Measurement Vehicle Testing
How Do We Test Vehicles? • testing? • Vehicle is tested on a dyno to simulate the effect of road load (e.g. aerodynamic drag) and vehicle inertia • Test cycle of actual on road speed is used to simulate real world driving • Standard test cycles – FTP, HWFET, SFTP-US06&SC03 FTP Test Cycle
Filters Cooling Fan Gas Analyzer Bench Dyno Controller Exhaust Emissions Measurement By Constant Volume Sampling (CVS) Method • The vehicle exhaust is diluted with ambient in a dilution tunnel to prevent water condensation • The CVS measures and samples exhaust gas volume in Tedlar bags • The analyzers measure the concentration of gaseous pollutants in Tedlar bags and in real time Blower Driver’s Aid Engine Cat Dilution Tunnel CVS DYNO Ambient Air Constant Flow
PM Sampling • Particulate matter samplers collect PM from the dilution tunnel onto filters • Filters are weighed in a clean room in the MLD Lab to determine PM mass emissions • Filters can also be subjected to the following chemical analyses: • Elemental carbon (EC)/Organic carbon (OC) • Ions – sodium, sulfates and nitrates • Elements – metals • Large filter PM samples can also be extracted for use in bioassay or other toxicological analyses
Alcohol/Carbonyl Sampling • testing? • Types of tests we use • How vehicle is • Exhaust can also be passed through impingers and DNPH cartridges to collect alcohol and carbonyl samples respectively • Samples are submitted for analysis by the MLD Lab (DNPH: Dinitrophenylhydrazine)
HC Speciation Sampling • testing? • HC analyzer in the test cell measures only total HC • However sometimes we want to see the profile of exactly of which HC species are in the exhaust • In those cases samples are collected from the CVS bags into small bags for HC speciation analysis • Analysis done by the MLD Lab can identify over 200 HC species • Types of tests we use • How vehicle is
Vehicle Testing System (VTS) • Data are gathered by VTS • VTS performs the calculations and provides gram per mile emissions data • Data are verified and accepted by test and project engineers • Final accepted data are then stored in the Vehicle Emissions Data System
What Are We Planning For The Future? • 4-WD testing • SULEV testing • LEVIII PM testing method development– defining the limitations of filter based PM sampling methods • CFR Part 1066 – new testing requirements for LDV
Conclusion/Q&A • Appreciation to VETS staff • Questions
Ray Sotelo, Jose Armas (cross-training), Richard Melnyk, Tuyen Dinh, Mang Zhang, Phuong Nguyen, Shiyan Chen and Paul Moone (not in picture)