1. Technology for a better society Oslo, June 2. 2016, LEO seminar 1 By Truls Berge SINTEF ICT, Dept. of Acoustics LEO – Results from noise measurements and possible reduction of traffic noise

2. Technology for a better society LEO – Measurements of tyre/road noise ("rolling noise"), including tyres developed for electric vehicles. 2 Main objective: To investigate the optimized combination of tyre and road surface, which can reduce the overall road traffic noise. 3 basic measurement procedures have been used: - CPX (Close proximity method) : Trailer and vehicle - Controlled pass-by measurements (CPB-microphone 7.5 m from centre of driving lane and at 1.2 m height). - Measurements on the laboratory drum facilities of TUG/Poland. NOTE: No measurements of internal noise inside the vehicles have been made. No measurements according to the EU tyre noise labelling system has been made (ECE Reg.117 on a smooth ISO test track). However, loading of CPX trailer is in line with ECE Reg.117 (and to some extent also tyre pressure). Some correlation/ranking analysis is feasible.

3. Technology for a better society LEO – Tyre/road noise measurements of passenger car tyres 3 Basic procedures: CPX measurements: Controlled pass-by measurements- vehicles: CPX Trailer Vehicle-mounted CPX

4. Technology for a better society Laboratory drum noise measurements by TUG: 4 Roadwheel facility with drum 1.7 m Roadwheel facility with drum 2.0 m

5. Technology for a better society Tyres designed for electric vehicles 5 Conti.eContact Michelin Energy E-V Dunlop ENASAVE Bridgestone 2030 ECOPIA EP500 OE-tyres for: VW.eGolf Renault ZOE Mitsubishi i-MiEV BMW i3 Dim: 205/55 R16 195/55 R16 175/55 R15 155/70 R19 (195/50 R18)

6. Technology for a better society LEO –Tyres used for measurements: Left: Tyres selected by TUG Right: Tyres selected by SINTEF 6 CONVENTIONAL TYRES T1066WANLIS-1200 195/60R15 88H M+S 4812 T1067CONTINENTALCONTIECOCONTACT 5195/60R15 88H1213 T1071VREDESTEINQUATRAC 3 195/60R15 88V M+S 3712 T1072YOKOHAMAWdrive 195/50R15 88T M+S 1812 T1079BRIDGESTONEECOPIA EP001S195/65R15 91H4612 T1080MICHELINENERGY SAVER X GREEN215/55R17 94H1712 T1081DUNLOPSPORT BLURESPONSE195/65R15 91H2413 T1082MICHELIN ENERGY SAVER + Extra Load X GREEN 195/65R15 95T313 T1093 NOKIANHAKKA GREEN195/65R15 95T1214 TYRES FOR ELECTRIC VEHICLES T1083MICHELIN ENERGY EV GREEN195/55R16 91Q1212 T1095DUNLOPENASAVE 2030175/55R15 77V3911

7. Technology for a better society Roads used for CPX measurements: 7 CountryNoSurface codeSurface type Norway1NOR1-SMA11Dense 2NOR2-SMA16Dense 3NOR3-SMA11Dense 4NOR4-SMA16Dense 5NOR5-SMA16Dense 6NOR6-SMA8Dense 7NOR7-SMA11Dense Poland8GDOW-DPACDouble layer porous 8/16 9GDOW-SMA8Dense 10PERS-PL1Poroelastic 11PERS-PL1-REF-SMA11Dense 12PG-SMA8-GDRDense 13KOS-SMA11Dense 14KOS-SMA11-RDense Measurement speed: 50 km/h on all surfaces Measurement speed: 80 km/h on surfaces 1 to 5 in Norway and 9, 13 and 14 in Poland

8. Technology for a better society Selected measurement results: CPX – Norway (50 km/h) 8 1. "Standard" Norwegian surface: SMA11 2. "Rough" Norwegian surface: SMA16

9. Technology for a better society Selected measurement results: CPX – Poland (50 km/h) 9 1. SMA11 2. Double layer porous 3. Poroelastic

10. Technology for a better society Potential reduction of tyre/road noise, by a combination of a low noise road surface and the EV tyre with the lowest noise levels (optimized theoretical values): 10 Reference: SMA11 (Norway): Based on previous projects in Norway, related to tyre/road noise measurements: SMA16 replaced by SMA8: -2 dB + best EV tyre: total: -4 dB SMA11 replaced by SMA8: -1 dB + best EV tyre: total: -3 dB SMA8 SMA8+EV DPAC PERS

11. Technology for a better society Correlation with EU noise label values: 11 EU label values are measured on an ISO 10844 surface (a dense asphalt concrete surface, DAC8, same max chipping size as SMA8)

12. Technology for a better society CPB and CPX measurements, using vehicles: 12 VW eGolf, Conti.eContact, 205/55 R16 VW Golf 2,0 TDI, Bridgestone Turanza ER300, 225/45 R17 BMWi3, Bridgestone Ecopia EP500, 155/60 R19

13. Technology for a better society EV and ICE measurement results: controlled pass-by levels (CPB) 13 JAPANESE INVESTIGATION: 0-30 km/h LEO MEASUREMENTS: CPB (cruise-by, constant speed 20-60 km/h - engine on)

14. Technology for a better society This table show the input data of reduction of tyre/road noise levels ("rolling noise") for 6 scenarios, with different combinations of low noise tyres and road surfaces. The input data is used for calculations of reduction of the overall traffic noise levels (Lden). 14 1) DPAC = Double Layer Porous 2) PERS = Poroelastic surface Reference road surface: DAC11 NoScenario Noise reduction, dB 1 Reference road surface, with average tyres 0 2 Reference road surface, replacement with best EV tyres -2 3 Replacement with SMA8, and best EV tyres -4 4 Replacement with DPAC 1), and average of EV tyres -6 5 Replacement with DPAC, and best of EV tyres -8 6 Replacement with PERS 2), and best of EV tyres -10

15. Technology for a better society Calculation model: TRANECAM (TRAaffic NoisE Calculation Model): 15 Model developed by Heinz Steven, Germany 2 sets of vehicle fleet composition: 1) Norway 2) EU/Poland 4 road categories: Share of EV in the traffic mix: 2 % (0 % for EU/Poland), 3 %, 5 %, 10 % and 25 %. For EVs: 3 categories of tyre/road noise levels: Small: reference L roll = 75% share of EV tyre fleet Medium: L roll +0,5 dB = 15% Large: L roll +1 dB = 10% Results includes effect of new vehicle noise limits (EU Directive 540/2014 – M and N type of vehicles), effective from July 2016 (Phase 1)+ new limits (Phase 2 and 3:2022-2027) Calculations of changes in Lden up to the year 2030. (Lden =day, evening, night –weighted average traffic noise levels.) No Road category Speed limits, km/h Norway/Poland ADT % HDV 1 Motorway100/1204000023 2 Rural Trunk Road80/901500012 3 Urban City Trunk50400009.5 4 Urban Access Residential3010004.3

16. Technology for a better society Potential reduction of Lden (Norway)(city conditions 30-50 km/h): 16 3 scenarios: Blue curve: "Do nothing" – just the effect of international regulations (EU/ECE) on vehicles and tyres: Orange curve: Replace reference road surface with SMA8 and low noise (EV) tyres. Grey curve: Replace reference road surface with double layer porous asphalt (DPAC) and low noise tyres For rural roads and motorways, the effect of EU/ECE regulations is appr. 2.2-2.3 dB in 2030

17. Technology for a better society The "optimum" scenario: A combination of a poroelastic road surface (PERS) and low noise tyres. Suitable for "hotspots" (?). Expensive, but costs can be comparable to very high noise barriers or façade insulation (calculations for city/residential roads): 17

18. Technology for a better society Influence of increased share of % EV in the traffic flow: 18 Increasing the share of % EV (or PHEV in electric mode), has only a minor influence (~ 0.3 dB) on the Lden-levels. The main reason is that the overall noise emission of passenger cars is dominated by tyre/road noise also under urban conditions (30 km/h and above, and EVs/PEVs has no "combustion" noise).

19. Technology for a better society Conclusions: 19 OE-tyres (for new vehicles) are chosen by the manufacturer - to meet many different performance criteria. Noise and rolling resistance is only two…(see also presentation by Erik de Graaff on triple AAA-tyres). Tyre labelling values do not correlate well with how the noise behaviour is on typical rough textured Norwegian roads. Tests of "standard" porous road surfaces in Norway (single and double layers, project "Miljøvennlige vegdekker" 2005-2008) showed clogging after 1-2 winter seasons, most likely due to the use of studded tyres and winter conditions. More research are needed. One solution: Optimized thin layers? (ref. to Denmark) Laboratory tests of poroelastic surfaces (ref. PERSUADE project) have shown a potential to reduce particle emissions (wear) from the use of studded tyres with up to 90 %, compared to normal asphalt (the surface is "elastic"). As shown in the LEO project, such a surface can reduce traffic noise levels (Lden) up to 7 dB. Problems/challenges: Durability and costs (see also presentation by Luc Goubert).

20. Technology for a better society Thank you for your attention! 20 Final solution: small "tyres" ??