Temperature influence on tyre/road noise frequency spectra

Transcription

1 Temperature influence on tyre/road noise frequency spectra Piotr MIODUSZEWSKI 1 ; Stanisław TARYMA 2 ; Ryszard WOŹNIAK 3 1,2,3 Gdańsk University of Technology, Poland ABSTRACT The correction for temperature effect on measured tyre/road noise is very important as it may be one of the main sources of errors in measurement results due to substantial influence of this parameter on obtained values. The latest version of the Technical Specification ISO/CD TS about Temperature Corrections contains a proposal of correction procedure for normalizing measured noise levels to a reference air temperature of 20 ºC. This procedure is currently neutral with respect to frequency as it only refers to the overall A-weighted sound level. But it is already prepared to be filled with frequency dependent coefficients when such a data are available. An extensive studies of how temperature affects the tyre/road noise measured on a road using the CPX method and in laboratory with tyres rolling on drums equipped with replica road surfaces were conducted at the Gdansk University of Technology in Poland. Overall A-weighted sound levels and the one-third octave band frequency spectra were acquired during the tests. The temperature correction coefficients for overall sound levels were derived and published at previous Internoise conferences in 2014 and The temperature influence on measured tyre/road noise one-third octave band frequency spectra are presented and discussed in this paper. Keywords: tyre/road noise, temperature influence, measurement methods I-INCE Classification of Subjects Number(s): INTRODUCTION Ambient air and road surface temperatures substantially affect the road vehicle noise emission, not the least tyre/road noise [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]. A correction for the temperature effect on tyre/road noise is very important as it may be one of the main sources of errors in measurement results due to the substantial effect of this parameter on obtained values. A detailed correction procedure is still under consideration and preparation for standardization in the ISO working group ISO/TC 43/SC 1/WG 27. The latest version of the ISO Technical Specification ISO/CD TS [11], substantially implemented also into the Technical Specification ISO/CD TS [12] which is about to be published this year, contains a proposal of correction procedure for normalizing obtained noise levels to a reference air temperature of 20 ºC. Each measured A-weighted CPX level shall be corrected using the following formula: C T,t = γ t (T - T ref ) (1) where: C T,t γ t T T ref - is the CPX level correction for temperature T for tyre t (in db), - is the temperature coefficient for tyre t (in db/ºc), - is the air temperature during the measurement, - is the reference air temperature (20 ºC). 1 pmiodusz@pg.gda.pl 2 staryma@pg.gda.pl 3 rwozniak@pg.gda.pl 4924

2 It has been found that for both tyres P1 and H1 specified in the ISO/TS the temperature coefficients γ t are approximately equal [13, 14, 3, 4] and that they depend somewhat on speed (relation is linear) [8, 14, 10]. It has been also found that the coefficients differ to some extent depending on the main type and condition (porosity) of a road surface [2, 3, 11, 12, 13]. The values of γ t are given by the formulas where v is the test speed in km/h: - for dense asphaltic surfaces (such as DAC, SMA, chip seals): - for cement concrete surfaces (of all types): - for porous asphalt surfaces (not seriously clogged): γ P1 = γ H1 = v (2) γ P1 = γ H1 = v (3) γ P1 = γ H1 = v (4) The temperature correction procedure is neutral with respect to frequency as it only refers to the overall A-weighted sound pressure level. Currently available data [7, 8, 15] show that the temperature influence is the highest at high frequencies, little lower at low frequencies and the lowest at around 1000 Hz. The peak frequency for tyre/road noise is usually around Hz what means that this dominant frequency is affected by temperature to a much lesser degree. The correction should ideally be made based on spectra and the procedure is already prepared for this when such a data will be available. But currently, in order to avoid a discrepancy between separately measured overall levels and the same calculated from spectra, the same correction is applied for all frequencies. 2. EXPERIMENTS According to the ISO/CD TS specification (and as well) the proposed temperature correction procedure shall be applied only if air temperatures are within 5 and 35 ºC. This is consistent with allowed temperature range for measurements using Close-Proximity (CPX) method (according to ISO/FDIS [16]) or using Statistical Pass-By (SPB) method (according to ISO [17]). An extensive studies of how temperature affects tyre/road noise measurements performed both on the road using the CPX method and in the laboratory with tyres rolling on drums equipped with replica road surfaces were conducted by the Gdansk University of Technology in Poland. The A-weighted sound pressure levels and the one-third octave band frequency spectra were acquired during the tests. 2.1 Road measurements An outdoor experiment started in the winter of 2013 and finished in the summer of Tyre/road noise measurements according to the CPX method, using the one wheel Tiresonic Mk4 CPX trailer [18], were performed in six selected days within that period to obtain an even temperature distribution within the desired range from 5 to 35 ºC. During the experiment the air temperature was changing in a range from 3 to 28 ºC. At the same time the acquired road surface temperature was within a range from 10 to 36 ºC. Ten passenger car tyres including the two reference ones according to the latest version of ISO/CD TS specification [12] (designated P1 and H1 in the standard [16]) were tested at a section of two years old SMA surface with 8 mm maximum aggregate size with two test speeds: 50 and 80 km/h. The tyre P1 is standardized in ASTM F2493. The H1 is a light truck tyre but run at the same load and inflation as the passenger car tyres. The selection of other tyres was based on tyres of similar size, currently available on the market, EU labeled one up to three bars regarding the external noise emission (ranging from 68 to 73 db) and class A to E regarding both: fuel efficiency and wet grip. Two of them were tyres specially designed for electric vehicles (designated 1076 and 1083). Tyre 1071 was an all-season tyre, all others were summer tyres. Detailed data regarding the selected tyres are presented in Table 1, their photos can be found in [9]. 4925

3 Table 1 Parameters of tyres selected for road measurements Designation Manufacturer Tread Size Date code Shore Hardness Fuel efficiency EU Labelling Wet grip External noise Noise level 1077 (P1) UNIROYAL TIGER PAW P225/60R16 97S (H1) AVON SUPERVAN AV4 195R14C 106/104N WANLI S /60R15 88H E E ))) CONTINENTAL ContiEcoContact 5 195/60R15 88H B B )) VREDESTEIN QUATRAC 3 195/60R15 88V E C ) AVON ZV5 195/65R15 91V C C )) CONTINENTAL Conti.eContact 195/50R18 90T A B )) BRIDGESTONE ECOPIA EP001S 195/65R15 91H A A )) DUNLOP Sport BlueResponse 195/65R15 91H B A ) MICHELIN ENERGY E-V 195/55R16 91Q A A )) Laboratory measurements Following the road measurements, a laboratory experiment was conducted in the autumn of 2014 at the Gdańsk University of Technology in Poland. Three facilities with drums having an outer diameter of 1.5, 1.7 and 2.0 m were used. The two smaller drums are designed for testing of passenger car tyres, the larger one is for truck tyres. The air temperature in the laboratory room was controlled using a powerful climate control unit (chiller/heater) within a range from 6 to 36 ºC with a step of 10 ºC. At the same time the measured replica road surface temperature was changing from 8 to 40 ºC. Twelve passenger car tyres, including two sets of reference tyres (P1 and H1) of different tread rubber hardness, and two truck tyres (designated with numbers 1084 and 1085) were tested in strictly controlled laboratory conditions. The selection of other tyres was based on the same principles as for the road experiment using the CPX method performed in 2013/2014. The tyres designated 1076 and 1120 were especially designed for electric vehicles. All selected tyres were summer tyres with the exception of tyre 1071 which was all-season one. Seven of the selected passenger car tyres were previously tested during that road measurements. Detailed data regarding the selected tyres are presented in Table 2, their photos can be found in [10]. Table 2 Parameters of tyres selected for laboratory experiment Designation Manufacturer Tread Size Date code Shore Hardness Fuel efficiency EU Labelling Wet grip External noise Noise level 1097 (P1) UNIROYAL TIGER PAW P225/60R16 97S (H1) AVON SUPERVAN AV4 195R14C 106/104N (P1) UNIROYAL TIGER PAW P225/60R16 97S (H1) AVON SUPERVAN AV4 195R14C 106/104N MICHELIN Primacy HP 225/60R16 98V E B )) WANLI S /60R15 88H E E ))) CONTINENTAL ContiEcoContact 5 195/60R15 88H B B )) VREDESTEIN QUATRAC 3 195/60R15 88V E C ) CONTINENTAL Conti.eContact 195/50R18 90T A B )) DUNLOP Sport BlueResponse 195/65R15 91H B A ) PIRELLI CINTURATO P1 195/60R15 88H C B )) BRIDGESTONE ECOPIA EP /70R19 84Q C B )) DUNLOP SP /65R K BRIDGESTONE R /65R K

4 Tyre/road noise measurements of passenger car tyres were performed on two smaller drums at the speeds of 50, 80 and 100 km/h on the following three replica road surfaces: - DAC12r: Dense Asphalt Concrete, with max. aggregate size of 12 mm; a very smooth-textured surface, with an MPD of 0.4 mm (MPD according to ISO ), - SD11r: Surface Dressing, with max. aggregate size of 11 mm; a very rough-textured surface, with an MPD of 2.0 mm, - PERS: Poroelastic Road Surface, developed within the EU project PERSUADE [19, 20], consisting of a hard aggregate with max. size of 4 mm, a soft aggregate of rubber granules from recycled tyres (more than 40 % of the total solid volume) and a polyurethane binder; air voids content is more than 25 % of the overall volume [21]. The truck tyres were tested with speeds of 50 and 80 km/h on the drum facility equipped with the following three replica road surfaces: - DAC16r: Dense Asphalt Concrete, with max. aggregate size of 16 mm; a very smooth-textured surface, - ISOr: Actual test track surface according to ISO 10844:1994 standard; a medium-textured surface, with an MPD of 0.85 mm, - PERS: Poroelastic Road Surface (see the description above). 3. TEMPERATURE EFFECT ON SOUND PRESSURE LEVELS It is assumed that the noise-temperature relation is essentially linear phenomena [2, 3, 11, 13], thus the temperature correction coefficients were derived based on linear regression analysis. The results of performed road and laboratory measurements were studied in details and, in the meaning of temperature correction coefficients for overall A-weighted sound pressure levels, were presented, discussed and published at previous Internoise conferences in 2014 [9] and 2015 [10]. At the latter conference a separate paper devoted to the phenomenon of speed effect on the temperature correction was presented [8]. This paper was based, among others, on the results of these experiments. 4. RELATIONSHIP BETWEEN LABORATORY AND OUTDOOR CONDITIONS Analyzing the temperature data acquired during laboratory tests an almost perfect relationship between air and replica road surface temperatures was found [10]. But the slope of regression lines, of approximately 1.0, differs from the slope (of 1.4) obtained during the field experiment [9]. When performing tests on a drum facility one should take into account that in a laboratory usually there is lack of sun radiation affecting road surface temperature in outdoor conditions. Also the cooling effect related to air flow around the test tyre and cooling effect by the tyre contact with the road surface differ from field test conditions. On the other hand, when performing road measurements one should consider surface albedo, sun and cloud conditions as well as rain history influencing the road surface temperature significantly [9]. It was found in the literature [3] that the temperature coefficient when using air is approximately 1.8 times the coefficient when using road surface temperatures. Based on the findings it was proposed by the authors in [10] to record both air and road temperatures and calculate a composite temperature correction coefficient for laboratory measurements to compare the derived values with correction coefficients obtained with the CPX method. This will compensate the values for the laboratory conditions like the lack of sun radiation in the laboratory room. It should be done according to the formula: γ c = (γ a + γ r 1.8) / 2 (5) where: γ c γ a γ r - is the composite temperature correction coefficient (in db/ºc), - is the temperature correction coefficient based on air temperature (in db/ºc), - is the temperature correction coefficient based on road surface temperature (in db/ºc). 4927

5 When only air temperature is acquired during laboratory measurements, then the composite temperature correction coefficient for laboratory measurements should be calculated according to the following simple formula: γ c = γ a 1.4 (6) where: γ c - is the composite temperature correction coefficient (in db/ºc), - is the temperature correction coefficient based on air temperature (in db/ºc). γ a 5. EVALUATION OF NOISE-TEMPERATURE CORRELATION The A-weighted third-octave band noise frequency spectra recorded separately by front and rear microphones placed in the ISO standard mandatory positions [16] were corrected for current measurement speed and averaged together before further analysis. Then noise-temperature slopes were derived for each third-octave band frequency. Correlation between temperature and each frequency band for each tyre, road surface and speed combination was evaluated taking into account two criterions: first the coefficient of determination R 2 and the second the standard error. Fundamentally a correlation was considered as acceptable when its coefficient of determination was above 0.6. In some cases when R 2 was lower than that value, then if the standard error was below 0.5 db the correlation was accepted. The second criterion accepts the cases with little or no temperature effect but well correlated. All other derived temperature correction coefficients not meeting the given criterions were excluded from future analysis. It was already revealed in previous publications reporting results from these experiments [9, 10] that two tyres showed very poor correlation between temperature and noise emission when tested on SMA8 surface using the CPX method. Also the correlation for some tyres when tested on the PERS surface in the laboratory was significantly lower in comparison to tests performed on the replicas of dense surfaces. Finally the correction coefficients with acceptable correlation were averaged over all test speeds. 6. TEMPERATURE EFFECT ON NOISE FREQUENCY SPECTRA All the derived temperature correction coefficients from laboratory measurements presented in this paper have been converted from the drum conditions to a typical outdoor condition according to the formula (5) given in chapter 4. When only air temperature was recorded during laboratory measurements the formula (6) was used instead. Thus all the presented values of temperature correction coefficients can be directly referenced to any literature data obtained by the CPX method. The coefficients derived for road measurements (for SMA8 road surface) presented in this paper are based on air temperature. 6.1 Passenger car tyres Figures 1 4 show the temperature effect on noise frequency spectra separately for tyre P1, tyre H1 and average of other tested passenger tyres respectively for SMA8, DAC12r, SD11r and PERS road surfaces. The derived values for low, mid and high frequency range are presented in Table 3. Additionally the temperature effect on overall sound pressure level is shown in the table. Different distribution of the temperature correction coefficient within noise frequency bands was observed depending on the test road surface and particular tyre. One should remember that tyre/road noise dominates in mid frequency range, thus the values of correction coefficient from this range will dominate the temperature effect on overall noise levels. For the SMA8 pavement (tested outdoors) the highest values for ISO reference tyres were derived for frequencies of Hz and 1600 Hz. The P1 tyre has also a comparable coefficient value for 5000 Hz. Other tested tyres on this surface present similar values to reference tyres for low and mid frequency ranges. But unexpectedly for high frequency range the coefficients are 3 6 times higher. The temperature effect on noise generated by P1 tyre is similar for low (-0.05 db/ºc), mid (-0.06 db/ºc) and high (-0.05 db/ºc) frequency range. Similar characteristics can be observed for H1 tyre. The values are db/ºc for low, db/ºc for mid and db/ºc for high frequency ranges correspondingly. For the other tyres they are as follow: db/ºc, db/ºc and db/ºc. 4928

6 Figure 1 Temperature effect on noise frequency spectra for SMA8 road surface Figure 2 Temperature effect on noise frequency spectra for DAC12r replica road surface Figure 3 Temperature effect on noise frequency spectra for SD11r replica road surface 4929

7 Figure 4 Temperature effect on noise frequency spectra for PERS road surface Table 3 Temperature effect on noise frequency range for passenger car tyres Road surface Tyre Low frequencies ( Hz) Temperature correction coefficient [db/ o C] Mid frequencies ( Hz) High frequencies ( Hz) Overall noise level ( Hz) Tyre P SMA8 Tyre H Other tyres All tyres average Tyre P DAC12r Tyre H Other tyres All tyres average Tyre P SD11r Tyre H Other tyres All tyres average Tyre P PERS Tyre H Other tyres All tyres average Comparable conclusions can be derived when analyzing the results obtained during laboratory experiment for DAC12r replica road surface. Again the highest coefficient values for all tested tyres can be observed for the same third-octave bands and additionally for frequencies of 315 Hz and 2000 Hz. In case of the other tyres, in the frequency range Hz the values of temperature coefficients were about half as big in comparison to SMA8 surface. Detailed values of derived temperature coefficients for low, mid and high frequency range are given in Table 3. For the very rough-textured replica road surface (SD11r) the highest temperature coefficients for all tested tyres are localized in the mid frequency range. They are 2 3 times bigger than for low and high frequency range with the exception when the coefficient is about the same value for high frequency. For P1 reference tyre and for the other tyres the coefficient are significant also in high frequency range. The H1 reference tyre present a lower values of the coefficient in comparison to P1 and other tyres in this range. Quite different temperature-noise coefficient distribution over the frequency spectra was observed when tested tyres on the experimental poroelastic road surface (PERS). This surface has both elastic properties due to significant amount of rubber granules from recycled tyres (more than 40 % of the 4930

8 total solid volume) and porosity properties due to open structure (air voids content is more than 25 % of the overall volume). The temperature correction coefficient values are rather evenly distributed within the low frequency range for both ISO reference tyres. The P1 tyre has also similar value for the next frequency of 800 Hz. The coefficient values for the other tested tyres present a high diversity within this range with a rather small average. The highest values for all tested tyres are located in the mid frequency range when again for ISO tyres they are evenly distributed (except P1 for 800 Hz). For the other tyres a consistent increase of the coefficient with frequency can be observed within this range. The high frequency range in case of this surface is divided into two parts: first for frequencies from 1600 Hz to 2500 Hz and second from 3150 Hz to 5000 Hz. In the first part the values of calculated correction coefficient are positive (from up to db/ºc). The magnitude of coefficients in the second part is of about same value but sign is negative. This characteristics is valid for all tested tyres on this surface. 6.2 Truck tyres The two selected truck tyres were tested in laboratory conditions only. The temperature effect on noise frequency spectra for these tyres is shown in Figures 5 7 separately for DAC16r, ISOr and PERS replica road surfaces. The derived values for low, mid and high frequency range are presented in Table 4. Additionally the temperature effect on overall sound pressure level is shown in the table. Figure 5 Temperature effect on noise frequency spectra for DAC16r replica road surface for truck tyres Figure 6 Temperature effect on noise frequency spectra for DAC16r replica road surface for truck tyres 4931

9 Figure 7 Temperature effect on noise frequency spectra for PERS road surface for truck tyres Table 4 Temperature effect on noise frequency range for truck tyres Road surface Tyre Low frequencies ( Hz) Temperature correction coefficient [db/ o C] Mid frequencies ( Hz) High frequencies ( Hz) Overall noise level ( Hz) Tyre DAC16r Tyre Truck tyres average Tyre ISOr Tyre Truck tyres average Tyre PERS Tyre Truck tyres average The temperature correction coefficients derived for truck tyres when tested on laboratory drums are consistent to coefficients obtained for passenger car tyres. For the DAC16r replica road surface rather even distribution can be observed within the all frequency range with a peak (up to db/ºc) at 630 Hz and a small increase for mid frequencies. Small dip (up to db/ºc) can be noticed in high frequency range for 2500 Hz and 5000 Hz. Taking into account the average of the two tested tyres the same values of the coefficient were obtained for low and mid frequency range (-0.07 db/ºc) and slightly lower for high frequencies (-0.05 db/ºc). Also a rather even distribution was found for the other dense replica road surface (ISOr). Only a small increase can be observed for the frequency of 315 Hz. The temperature coefficient calculated as an average of both tested tyres is slightly higher for low frequency range (-0,10 db/ºc) than for mid and high range (-0.07 db/ºc). For the PERS surface, in opposite to both dense surfaces, a positive values of temperature coefficient were observed for mid frequency range and both positive and negative for high frequencies. Thus in comparison to the coefficient distribution for passenger car tyres tested on the same surface a shift of coefficient with positive values in the lower frequency direction occurred. The temperature effect on the overall noise level for truck tyres tested on PERS surface is very low (-0.01 db/ºc). 7. DISCUSSION This is a first approach to the analysis of temperature effect on tyre/road noise frequency spectra on the basis of data acquired from the extensive experiment established and conducted to extend the knowledge of this phenomena. Some simplifications were introduced at the beginning, namely the average of noise recorded by two microphones and the average for all tested speeds (two in case of road measurements and three for laboratory tests). 4932

10 Data available in the literature [7, 8, 15] show that the temperature influence is the highest at high frequencies, little lower at low frequencies and the lowest at around 1000 Hz. The results of the performed experiments are not fully consistent with those findings. Only for the SMA8 surface a small dip can be noticed for the frequency of 1000 Hz. For the very rough surface SD11r a significant peak was observed for this frequency. Also the highest values of derived temperature coefficient in high frequency range were noted only for other tyres tested on SMA8 surface. In case of ISO reference tyres the values were moderate. Literature data deal with only the ISO reference tyres, thus a discrepancy appears. An explanation may be the fact, that a majority of tests reported in literature were performed on relatively smooth road surfaces, although the most common. In case of very rough-textured road surfaces different noise generation mechanisms may dominate than for smooth-textured ones. Due to the introduced simplifications at the beginning of this study the authors haven t performed the analysis of noise generation mechanisms which shall be discussed when analyzing separately noise recorded by front and rear microphone. This will be done in the future study. Anyway, the temperature corrections coefficients derived on the base of the same data for overall noise levels are fully consistent with data available in literature [3, 4, 7, 8, 13]. This proves that there are no significant errors in the performed experiments and in the acquired data. 8. CONCLUSIONS The performed experiments, both the road measurements and the laboratory drum tests, confirmed the available literature data regarding temperature effect on tire/road noise. The derived temperature correction coefficients correlate very well with coefficients derived by other researchers and also with the values proposed by the Working Group ISO/TC 43/SC 1/WG 27 of the International Standard Organization, established to propose a standardized method for correcting the effect of temperature on road vehicle noise measurements. The proposed correction procedure is actually neutral with respect to frequency as it only refers to the overall A-weighted sound pressure levels. But ideally it should be based on spectra and this procedure is already prepared for this when such a data will be available. Currently the same correction is applied for all frequencies. The experiment showed differences in temperature effect on noise frequency spectra depending on a combination of tested tyre and road surface. A different temperature correction coefficient distribution over the frequency domain was observed for smooth-textured surfaces, different for rough-textured and a totally different for poroelastic ones. In general the distribution for both ISO reference tyres is rather similar but the tyres differ, sometimes significantly, in values of the temperature coefficient for particular third-octave band. Also some shifts were observed within the adjacent frequency bands. The tested truck tyres showed rather uniform coefficient distribution over frequency spectra and the derived coefficients were usually similar for both tyres. The distribution characteristics obtained on poroelastic surface is similar to the one for passenger car tyres. The temperature effect on tyre/road noise frequency spectra is rather complicated phenomena and definitely it needs more research. Especially the knowledge of temperature influence on noise generation mechanisms occurring in typical frequency ranges may enable to introduce in future a proper temperature correction for particular third-octave band within an entire frequency spectra domain. The research started already with this study will continue. ACKNOWLEDGEMENTS The work presented in this paper was partly performed in relation to the ongoing EU FP7 project ROSANNE ROlling resistance, Skid resistance ANd Noise Emission measurement standards for road surfaces (FP7/ ) financed by the European Commission grant agreement No Some of the measurements were performed within the Polish-Norwegian research project LEO Low Emission Optimised tyres and road surfaces for electric and hybrid vehicles funded by the Polish National Centre for Research and Development (NCBiR) within the Polish-Norwegian Research Programme, CORE (Grant Agreement /2013). The authors are very grateful for this financial support. 4933

11 REFERENCES 1. Sandberg U., Ejsmont J.A.: Tire/Road Noise Reference Book, INFORMEX Ejsmont & Sandberg, Handelsbolag, Printed by MODENA, Gdynia, Poland, (2002). 2. Sandberg U.: Semi-generic temperature corrections for tyre/road noise, Proc. of Internoise 2004, August 2004, Prague, Czech Republic (2004). 3. Sandberg U.: Standardized corrections for temperature influence on tire/road noise, Proc. of Internoise 2015, 9 12 August 2015, San Francisco, CA, USA (2015). 4. Bühlmann E., Ziegler T.: Temperature effects on tyre/road noise measurements and the main reasons for their variation, Proc. of Internoise, 2013, September 2013, Innsbruck, Austria (2013). 5. Jabben J.: Temperature effects on road traffic noise measurements, Proc. of Internoise 2011, 4-7 September 2011, Osaka, Japan (2011). 6. Bueno M., Luong J., Vinuela U., Teran F., Paje S.E.: Pavement temperature influence on close proximity tire/road noise, Applied Acoustics 73, (2011). 7. Anfosso-Ledee F., Pichaud Y.: Temperature Effect on Tyre-Road Noise, Applied Acoustics 68 (2007). 8. Bühlmann E., Ziegler T.: Temperature effects on tyre/road noise measurements, Proc. of Internoise 2011, 4-7 September 2011, Osaka, Japan (2011). 9. Mioduszewski P., Taryma S., Woźniak R.: Temperature influence on tyre/road noise of selected tyres, Proc. of Internoise 2014, November 2014, Melbourne, Australia, (2014). 10. Mioduszewski P., Ejsmont J., Taryma S., Woźniak R.: Temperature influence on tire/road noise evaluated by the drum method, Proc. of Internoise 2015, 9-12 August 2015, San Francisco, CA, USA (2015). 11. ISO/CD TS : 2016: Acoustics Temperature influence on tyre/road noise measurement Part 1: Correction for temperature when testing with the CPX method, ISO, Geneva, Switzerland (to be published). 12. ISO/CD TS : 2016: Acoustics Measurement of the influence of road surfaces on traffic noise Part 3: Reference tyres, ISO, Geneva, Switzerland (to be published in 2016). 13. Bühlmann E., van Blokland G.: "Temperature effects on tyre/road noise -- A review of empirical research". Proc. of Forum Acusticum 2014, 7-12 September 2014, Krakow, Poland (2014). 14. Sandberg, U., Mioduszewski, P.: Temperature influence on measurements of noise properties of road surfaces and possible normalization to a reference temperature, Deliverable D2.2 of project ROSANNE, available at (2016). 15. Bühlmann, E., Sandberg, U., Mioduszewski, P.: Speed dependency of temperature effects on road traffic noise, Proc. of Inter-Noise 2015, San Francisco, CA, USA (2015). 16. ISO/FDIS : Acoustics Method for measuring the influence of road surfaces on traffic noise Part 2: The close proximity method, Geneva, Switzerland: International Organization for Standardization (2016). 17. ISO : Acoustics Method for measuring the influence of road surfaces on traffic noise Part 1: The statistical pass-by method, Geneva, Switzerland: International Organization for Standardization (1997). 18. Mioduszewski P., Ejsmont J.A.: Tire/road noise measuring principles according to the Close Proximity Method, Tire Technology International: The Annual Review of Tire Materials and Tire Manufacturing Technology (2007). 19. Goubert, L.: "Developing a durable and ultra-low noise poroelastic pavement". Proc. of Internoise 2014, Melbourne, Australia (2014). 20. Sandberg, U., et al: "State-of-the-Art regarding poroelastic road surfaces". PERSUADE Deliverable D8.1, available: (2010). 21. Mioduszewski P., Ejsmont J., Taryma S., Woźniak R.: Temperature influence on tire/road noise on the poroelastic surface evaluated by the drum method. PERSUADE-TUG-R01-V01-WP , Technical Report R6.1, (2015). 4934