ASEP -- Revision of D/F and OICA methods -- GRB informal meeting #13 6-7 November 2008 JASIC
Main Differences between D/F and OICA proposal Discussion points N_anch N_urban (Statistical analysis) N_i (measured) Gap of Average and measured engine speed. Case of exceeding 2m/s^2 on gear i L_anch Lwot_limit (calculated by Kp and Annex3 limit) L_wot,i Consideration for low noise vehicles Sound slope Fixed 5dB/1000rpm Individual, but less than 7dB/1000rpm 5dB/1000rpm is average. A half of data base are higher slope. Tolerance 2dB 3dB Calculation for limit lines Lp_anch=[Lwot_limit – Lcrs50] Lp=Lp_anch+5dB/1000rpm [rpm] Lt=32Log(V[rpm]/V50)+Lcrs50 Lwot=[Lp+Lt] ---energy sum. Lp=[Lwot,i – Lcrs50 (or Lroll)] Lwot,j=Lp+Lcrs50+32Log(Vj/V50) (@j gear) Lwot=Lwot,j + slope(dB/1000rpm) [rpm] Anchor point
The vehicles which fail D/F and pass OICA < 0.0 0.1 to 0.5 0.6 < Fail Large difference between D/F and measured engine speed. These vehicles do not pass Annex3
How to define the engine speed for anchor point Nurban=2.2PMR-0.43 (n-n_idle)/(s-n_idle) Power to mass ratio Difference (ΔN=Measured value - Nurban)
The vehicles which fail D/F and pass OICA < 0.0 0.1 to 0.5 0.6 < Fail
Same results of Mod. D/F and OICA vehicle 1-45 D/F:Fail OICA:Pass D/F Proposal OICA Proposal D/F:Fail OICA:Pass Mod. D/F: Pass Engine speeds are used Ni and Ni+1 for anchor point Gear:3rd, Annex3,i : 4th
Same results of Mod. D/F and OICA vehicle 200-14 D/F:Fail OICA:Pass D/F Proposal OICA Proposal D/F:Fail OICA:Pass Mod. D/F: Pass Engine speeds are used Ni and Ni+1 for anchor point Gear:2nd , Annex3,i : 4th
The vehicles which fail D/F and pass OICA < 0.0 0.1 to 0.5 0.6 < Fail Still different
The vehicles which fail D/F and pass OICA < 0.0 0.1 to 0.5 0.6 < Fail
Engine speeds are used Ni and Ni+1 for anchor point N1 diesel vehicle 3-01 D/F Proposal OICA Proposal D/F:Fail OICA:Pass Engine speeds are used Ni and Ni+1 for anchor point Mod. D/F: Fail Tolerance 2dB : Pass Sound Slope = 5.7dB/1000rpm N1 might be considered separately, because N1 vehicle’s design is different from passenger car’s. Gear:2nd , Annex3,i : 3rd
The vehicles which fail D/F and pass OICA < 0.0 0.1 to 0.5 0.6 < Fail Fail due to changing tolerance 3dB to 2dB
Influence of tolerance Vehicle 200-4 D/F Proposal OICA Proposal D/F:Fail OICA:Pass Mod. D/F: Fail Tolerance 2dB: Fail It seems that the tolerance 3dB may be necessary. Gear:2nd , Annex3,i : 5th
Influence of tolerance Vehicle 200-10 D/F Proposal OICA Proposal D/F:Fail OICA:Pass Mod. D/F: Fail Tolerance 2dB: Fail It seems that the tolerance 3dB may be necessary. Gear:3rd , Annex3,i : 4th
Distribution of sound slope Average 2nd : 5 dB/1000rpm 3rd : 6 dB/1000rpm D/F(UBA) uses fixed value, 5dB/1000rpm
Risk of the fixed sound slope The difference of sound slope 1dB/1000rpm causes the difference 3dB at the maximum engine speed. 5dB/1000rpm is average for 2nd gear. Therefore, a half of vehicles have larger slope. The sound slope in D/F should be modified or may use the individual slope. Vehicle: 200-6 Gear:2nd , Annex3,i : 4th 6.0dB/1000rpm (2nd)
Anchor point for OICA proposal Gear:2nd , Annex3,i : 4th PMR=124 (Nwot,i; original) OICA Proposal (Nurban, i, i+1) The anchor points based on gear i, i+1, or 2 gears are in line with limit line Vehicle 100-22 Gear:2nd , Annex3,i : 4th PMR=124
Anchor point for OICA proposal Gear:2nd , Annex3,i : 4th , PMR=181 (Nwot,i; original) OICA Proposal (Nurban, i, i+1) The anchor points based on gear i, i+1, or 2 gears are in line with limit line Vehicle 200-10 Gear:2nd , Annex3,i : 4th , PMR=181
Summary (1) The result of D/F proposal with modified engine speed for anchor point is same as that of OICA method with 2dB tolerance. (But the tolerance should be optimized.) The sound slope in D/F should be modified or may use the individual slope. N1 might be considered separately, because N1 vehicle’s design is different from passenger car’s. However, D-range tests on automatic transmission have the other problem.
Consideration for modifyiing the OICA proposal on D-range test for CVT OICA proposal compensate tyre nosie only at the anchor point. There is the influence of tyre noise at every point as well as at the anchor point, bcause the relationship between vehicle speed and engine speed is not liner in case of CVT. D/F proposal cannot create a limit line. Vehicle 1-10 Gear:D-range , Annex3,i : D-range
Non linear relationship Vehicle 1-10 1000 2000 3000 4000 5000 6000 20 30 40 50 60 70 80 90 100 Vehicle speed(Vbb), km/h Engine speed(Nbb), rpm D-range Annex3(D) Nmax Vehicle 1-12 1000 2000 3000 4000 5000 6000 20 30 40 50 60 70 80 90 100 Vehicle speed(Vbb), km/h Engine speed(Nbb), rpm D-range Annex3(D) Nmax Vehicle 1-14 1000 2000 3000 4000 5000 6000 20 30 40 50 60 70 80 90 100 Vehicle speed(Vbb), km/h Engine speed(Nbb), rpm D-range Annex3(D) Nmax Vehicle 1-16 1000 2000 3000 4000 5000 6000 20 30 40 50 60 70 80 90 100 Vehicle speed(Vbb), km/h Engine speed(Nbb), rpm ASEP(D) Annex3(D) Nmax
Modified OICA proposal for D-range test Vehicle 1-10 A B rpm dB B A Same engine speed but different vehicle speed 0.7 dB Influence of tyre noise Should use maximum vehcle speed within ASEP test for the calculation of the anchor point
Modified OICA proposal for D-range test Vehicle:ASEP 1-10 (original) Vehicle:ASEP 1-10 (mod.) Vehicle:ASEP 1-12 (original) Vehicle:ASEP 1-12 (Mod.)
Modified OICA proposal for D-range test Vehicle:ASEP 1-14 (original) Vehicle:ASEP 1-14 (Mod.) Vehicle:ASEP 1-16 (original) Vehicle:ASEP 1-16 (Mod.)
Comparison between the D/F and OICA proposal on D-range test for CVT D/F D-range test OICA D-range test Step-1 : Measure_Annex3 : Lurban, Lcrs Step-2 : Measure ASEP_data : N@Lmax, Lmax Step-3 : Calculate Anchor Point Step-4 : Calculate Limit Curve L_ASEP(n,v) Step-1 : Same Step-2 : Measure ASEP_data : N@BB, Lmax Step-3 : Calculate Anchor Point Step-4 : Calculate Limit line L_ASEP(slope) Repeat Step2 to Step 4 for the number of ASEP data A lot of calculation steps
Consideration for low noise vehicles Near Annex3 limit Low noise Vehicle 1-47 Lurban=69.0dB Lurban=71.5dB 72-69=3dB margine The reference lines of D/F and OICA are same Should add a margine of Annex3 limit Vehicle 99-8 Vehicle 1-45 Lurban=69.2dB Lurban=69.2dB Lurban=72.4dB 72-69.2 =2.8dB margine
To revise the OICA proposal; Summary (2) To revise the OICA proposal; Should be revised compensation of anchor point in case of D-range test for the automatic transmission. Should be considered a margin of Annex3 to apply to ASEP for low noise vehicles.
Exemption (Simplification)
Narrow range of engine speed for CVT 398 rpm (7.7 %) 511 rpm (9.8 %) Vehicle 1-12 Vehicle 1-10 492 rpm (10.0 %) 512 rpm (11.7 %) 534 rpm (11.0 %) 538 rpm (11.1 %) Vehicle 1-14 201 rpm (3.3) % 225 rpm (4.4 %) Vehicle 1-16 Is it necessary to test ASEP for such vehicles?
How about lower engine speed of Annex3? There is no example that exceeds the noise level of Annex3 below the engine speed of Annex3.
Engine speed during Annex3 (1)
Engine speed during Annex3 (2) Lower engine speed are already covered in Annex 3
Summary (3) May skip ASEP test when Annex3 covers the engine speed in ASEP. Not necessary to test below Annex3 (anchor point)
Appendix