Pilot phase - Learnings First indication of learnings from pilot phase which is ongoing LOT 4 ADVISORY BOARD MEETING BRUSSELS ACEA CO2WG TF1 WGCO2 Monday, HDV, 23 November TF1 2015
To be finalized or rather analyzed in expert group! TF1 Engine testing 1. Modification in engine tool (WHTC correction tool) due to specific test bench layouts necessary. 2. Minor procedural definitions need to be finally clarified in detail. 3. Engine auxiliaries: New FC reduction technologies (e.g. regulated water and oil pump) have to be considered appropriately in Technical Annex. Procedure basically agreed. 4. Engine family/co2 cluster concept must be finally elaborated 5. Proposal for CO2/FC extension of existing engine emission COP procedure. 6. Definitions for CO2 and NOx emission demonstration are different. 7. WHTC correction factors for CO2 have not to be determined on the same cycle than NOx emission reporting. Influence on CO2 engine input data has to be carefully elaborated on the basis of pilot study results. 2
TF1 Transmission testing 1. Temperatures (wording was already changed by expert group) The wording defining the allowed temperature range was changed to be comparable to the technical annex of axles. This leads to the possibility to do measurements without an additional heating. 2. Calculation of uncertainty factor w_para to be reviewed The factors for the parasitic loads (w_para:100%, 50%, and 20%) seem to be very high. An option 3 measurement with a test rig setup which is not perfect (for example only one bearing beside the torque sensor w_para=100%) leads to worse values than using option 2. 3. The test procedure according to Option 2 is possible to follow and produces relevant and meaningful results, minor clarifications are necessary. 4. Transmission oil temperature in the test must be revised. Different temperature than in the vehicle gives incitement to introduce oil that is optimal for test conditions but sub-optimal for actual conditions. 5. Transmission measurement ranges to be revised to cover all load points for all vehicles 3
TF1 Axle testing (1/2) 1. Calculation of parasitic losses to be reviewed 2. Axle measurements need to be extended to cover all VECTO load points 3. Measurement of hub reduction gear axles in 2 machine test rig layout (L-configuration) brings along technical problems regarding cooling. (See technical annex Item 3.2.3) Proposal: hub reduction gear axles shall also be measured in a 3 machine layout 4. The tolerances considering the controllability of the set point should be redefined. They can currently not be met for all measuring points. As an alternative, a procedure for set points which do not comply with the requested repeat accuracy should be defined 5. It was possible to successfully complete the axle test and the required data. 6. Technical Annex contains many details in measurement conditions and design specifications: that are not objectively verifiable in a practical way neither have a substantial contribution to the CO2 contribution of the axle to the vehicle ( f.e. distance gear to wall, alignment of axle, sealing specs.) Design characteristics for family concept are too detailed for use in practice 4
TF1 Axle testing (2/2) 9. Conditions are not always clear specified for verification, e.g.: Oil filling level Lack of bandwidth specifications 10. Measurement range is not defined in a practical way, e.g. has too much interaction with engine / vehicle release data Maximum power to much dependent of actual vehicle release data Test range for torques and extrapolation method. Test range for minimum rpm not practical (tyres change!) 11. Calibration requirements Not always clearly specified how to make these verifiable in practice (e.g. rpm) 12. Descriptions in T.A. not always clear and unambiguous (example: text about run-in times etc.) 13. Review technical annex in expert group (same for all annexes): Which information can be removed because it is not necessary e.g. does not have substantial influence on the CO2 contribution of the axle Which data entries and tolerances should be extended to avoid unnecessary test burden and limitations. Which descriptions of conditions should be adapted to make these objectively verifiable in practice. To improve the text where it is unclear, incomplete or ambiguous Apply commonly used homologation jargon & procedures. 5
TF1 Air drag testing (1/2) 1. CSE tool to be improved: Measurement data (sets) are accepted by the CSE tool although Technical Annex is not fulfilled. Errors should be removed. Validation check needs too much time. The results should be available during the test. Error messages often unclear and should be improved A possibility should be created to allow for diagnosis of unaccepted data Enable first processing all measurement data in one direction and consequently all data in the other direction (as is allowed in the technical annex) 2. Review tolerances/handling (minimum limit of valid laps is difficult to reach and to detect when minimum is reached) Ambient conditions and torque variations Maximum allowed peak torque variation, especially on low speed rounds Minimum drift limits of the torque wheels difficult to reach Lifting the torque measuring axle on track Torque limitation representing brake drag and axle losses 3. Limits for ambient conditions need to be reviewed e.g. for tarmac temperatures. This might be dependent from test track. 4. At one OEM, the repeatability of CSE is low 6
TF1 Air drag testing (2/2) 4. Some class 1-3 truck combinations exceed speed corridor for low-speed measurements (10-15 km/h) due to the standard powertrain configuration 5. Kistler does not guarantee torque accuracy as required in Technical Annex. The Kistler torque quality spec should be accepted or calibration procedure added 6. Calibration of the wind meter acc. to ISO 16622 cannot be met (low speed) or is not suitable (high speed). Review criteria 7. Requirements regarding trailers and boxes are strict. Box body dimensions to comply with should have tolerances for easier check by technical service (-> ClCCR) 8. General: Technical annex contains many recommendations that are not verifiable (no quantification) and often not necessary or redundant for legislation. These statements should be removed or moved to a best practices chapter 9. Review payload definition due to higher stability of torque & speed signal with higher weights 10. Review tyre pressure definition 7
TF1 SiCo test 1. Chassis dyno results are dependent on the measured force on the Kistler wheels, which seemed to drift more on these high load points than on-road. 2. On-road is difficult to control the engine load (more than just loading the combination to the right weight), so some variability between days is expected. 3. Zero-calibration of the test rims (Kistler) not possible for lack of space and due to test bench equipment (roller test bench and test cell height) 4. Axle oil temperature may be exceeded on the dyno, low temperature during on road test 5. Tolerances of the measurement equipment (Kistler Rims, dyno control, FC measurement) have to be defined 6. Definition of how the constant speed point (in SiCO test #1) have to be chosen from the.vdri (from the entire cycle as proposed by IVECO or with the conventions proposed by TuG) 8
TF1 VECTO calculations 1. The extrapolation method for axle and transmission test results should be implemented in VECTO 2. Data plausibility check produces unnecessary errors (checking axle operating points which cannot be reached and therefore not measured) 3. Maximum engine torque due to engine test procedure (tolerance & not installed aux) sometimes higher than the maximum input torque of the gearbox, resulting in VECTO error 9
TF1 additional Commission should also ask the TAA and the TS for their comments, based on the experience done in these months 10