The Nuts and Bolts of a Complete 1065 Audit

Transcription

1 The Nuts and Bolts of a Complete 1065 Audit 2012 PEMS Workshop: The Latest Tools and Techniques for In-Use Measurements March Presented By: Tanfeng (Sam) Cao Co-Authors: Kent Johnson, Thomas D. Durbin, Karl Oberguggenberger, Roland Wanker, Thomas Schimpl, and Volker Pointner University of California, Riverside Bourns College of Engineering Center for Environmental Research and Technology 1

2 Motivation and Background PEMS are being deployed by many users to assess real world emissions PEMS measurement can vary from setup, in-use, post processing, alignment, and data analysis 2

3 PEMS-MEL Absolute Humidty (grains/lb) ' Past Studies: Humidity Variations Weather shield not used 5 % positive kh bias Unit #1 Unit #2 Unit #3 Unit # Weather shield not used 2 % positive kh bias Weather shield used Both < 1% kh bias % negative kh bias -10 MEL Absoutle Humidity (grains/lb) 3

4 Motivation and Background PEMS are being deployed by many users to assess real world emissions PEMS measurements varies from setup, in-use, post processing, alignment, and data analysis 40 CFR Part 1065 is a comprehensive requirement to control uncertain of emissions measurements This talk will provide a summary of experiences and howto s on doing a complete 1065 audit on a newly developed PEMS 4

5 PEMS Audited: AVL s M.O.V.E. 493 Gaseous PEMS 5

6 40 CFR Part 1065 The Breakdown Table Genaral Measurement Apporach Verifications and Checks Subpart Reference Description A Applicability and General Provisions B Equipment Specifications C Measurement Instruments D Calibrations and Verifications E Engine Selection, Preparation, and Maintenance F Performing an Emission Test in the Laboratory G Calculations and Data Requirements H Engine Fluids, Test Fuels, Analytical Gases and Other Calibration Standards I Testing with Oxygenated Fuels J Field Testing and Portable Emission Measurement Systems K Definitions and Other Reference Information 6

7 40 CFR Part 1065 The Breakdown (sub D) Table 2. Applicable 1065 performance verifications for AVL 493 Gas PEMS Reference Description Requirement 301 Overview and general provisions n/a 305 Verifications for accuracy, repeatability, and noise. New 307 Linearity verification Routine Continuous gas analyzer system-response and updating-recording verification for gas analyzers continuously compensated for New other gas species. 315 Pressure, temperature, and dewpoint calibration New 342 Sample dryer verification New Vacuum-side leak verification Routine 350 H 2 O interference verification for CO 2 NDIR analyzers. New 355 H 2 O and CO 2 interference verification for CO NDIR New 360 FID optimization and verification New Non-stoichiometric raw exhaust FID O 2 interference New 372 NDUV analyzer HC and H 2 O interference verification New 376 Chiller NO 2 penetration New 1 Within in 35 days before testing 2 For osmotic membrane dryers only - within 35 days before testing 3 Repeat as needed upon good engineering judgement 7

8 How to Perform a 1065 Verification? Sample Dryer Verification Step 1. Read CFR 8

9 How to Perform a 1065 Verification? Step 2 Experimental setup 9

10 How to Perform a 1065 Verification? Step 4 Perform task Identify correct location Leak check/overflow Allow enough stabilization time Outlets Inlet 10

11 H 2 O Interference for CO 2 Analyzer H 2 O can interference with the NDIR analyzer s response to CO 2 Pass/fail criteria 0.0 ± 0.4% With the 2 stage chiller within the PEMS, the interference is minor 11

12 Table 3. Measurement system that require linearity verification Linearity Verification Measurement System Frequency Speed 1 Torque Electrical power Fuel flow rate Intake air flow rate Dilution air flow rate Diluted exhaust flow rate Raw exhaust flow rate Batch sampler flow rate Gas dividers Gas analyzers for laboratory testing Monthly 2 Gas analyzers for field testing Monthly PM balance Pressures Dewpoint 3 Analog to Digital 1 Within 35 days before testing 2 Within 370 days before testing 3 Inculde intake air, PM stabilization, and other T dew sensors Q: Which measurement systems needs linearity verification? Traditional linearity criteria y ref = y meas *a 1 +a 0, R linearity criteria Slope:0.99 a Correlation: R Zero: y min (a 1-1)+a 0 1% y max Error: SEE 1% y max 12

13 Linearity: The Setup Gas divider vs. individual bottles Ensure Gases are at primary standard ( ) Ensure gas divider used passes 1065 checks Perform at ranges you measure 13

14 ymeas (ppm of CO) Abs Eroor (ppm of CO) 1065 Linearity: Example y = 1.010x R² = yref (ppm of CO) Traditional linearity PASSED \ Linearity Parameters x min a1 1) ( a x SEE a 1 2 r x max 0 max y ref (ppm of CO) 1065 linearity 1065 Limit Status % 1% FAILED PASSED % 1% PASSED PASSED 14

15 Relative % Error to MEL Engine Dyno Last verification step for 1065 compliance ( (b)) Advantage of engine dyno vs. in-use Real world brake specific emission but with controlled ambient conditions Repeatability, direct comparison to a reference lab 25% 15% 5% -5% -15% bsnox bsco2 Exh Flow Exh Temp_C %

16 Conclusions and Recommendations PEMS need to be kept calibrated and maintained to ensure high quality data A complete 1065 audit helps user to gain confidence in reported data Recommended check: 90 ºF ambient 8 hour drift check 16

17 Acknowledgements Funding Sources AVL Technical Support AVL Technical Staff Don Pacocha Joe Valdez Ed O neil Kurt Bumiller Graduate Students Mohammad Yusuf Khan Undergraduate Students Rachael Hirst 17

18 Acronyms Support Slide PEMS Sensors portable emission measurement system OEM Original Equipment Manufacture DPF Diesel Particulate Filter DOC Diesel Oxidation Catalyst Regen Forced regenerations with OEM tools ECM Mods Recalibrated ECM to change NO x emissions levels DPF Wall flow diesel particulate filter 18

19 Temperature (C) Up Hill In-Use Ambient Temperatures Are 5/08/2008 Temperature Deviations Depending on PEMS Location Not All the Same Trailer Door Cab ATIS_00 ATIS_01 ATIS_02 ATIS_03 ATIS_04 Ambient down hill 60 lunch (engine off) F ATIS_04 ATIS_03 ATIS_02 ATIS_01 ATIS_00 ATIS_ :00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 Time (hh:mm) 19