Low rolling resistance tire

Low rolling resistance tires are designed to reduce the energy loss as a tire rolls, decreasing the required rolling effort — and in the case of automotive applications, improving vehicle fuel efficiency as approximately 5–15% of the fuel consumed by a typical gas car may be used to overcome rolling resistance.[1]

Such tires are now commonly installed as standard, either mandated by law or to meet eco labelling standards.

Measuring rolling resistance in tires

Rolling resistance can be expressed by the rolling resistance coefficient (RRC or Crr), which is the value of the rolling resistance force divided by the wheel load. A lower coefficient means the tires will use less energy to travel a certain distance. The coefficient is mostly considered as independent of speed, but for precise calculations it is tabled at several speeds or an additional speed-dependent part is used. The Society of Automotive Engineers (SAE) has developed test practices to measure the RRC of tires. These tests (SAE J1269 and SAE J2452) are usually performed on new tires.

When measured by using these standard test practices, most new passenger tires have reported RRCs ranging from 0.007 to 0.014.[2] In the case of bicycle tires, values of 0.0025 to 0.005 are achieved.[3] These coefficients are measured on rollers, with power meters on road surfaces, or with coast-down tests. In the latter two cases, the effect of air resistance must be subtracted or the tests performed at very low speeds. In 2009 The CEC used a rating called Rolling Resistance Force RRF. RRF and RRC, rolling resistance coefficient are very similar. Difference is taking the RRF and dividing it by the load(weight) to get RRC. So a Michelin Harmony tire rated at 9.45 RRF at 1000 pounds load would be .0095 RRC.[4][5]

In the early 2010s in Canada, Transport Canada tests were planned on a number of different tires mounted on 15 and 16-inch rims – the most common tire sizes in Canada at that time – to determine how rolling resistance is influenced by vehicle size, tire width and profile. Results will be used to inform Canadians about the types of low rolling resistance tires available in Canada, and whether they can help reduce fuel consumption and pollutants from passenger vehicles.[6] SAE J2452 is a standard defined by the Society of Automotive Engineers to define the rolling resistance of tires.

The rolling resistance coefficient (RRC) indicates the amount of force required to overcome the hysteresis of the material as the tire rolls. Tire pressure, vehicle weight and velocity all play a role in how much force is lost to rolling resistance.

The basic model equation for SAE J2452 is:

Rolling Resistance (N / lbs)

where:

is the tire inflation pressure (kPa / psi)
is the applied load for the vehicle weight (N / lbs)
is the vehicle speed (km/h / mph)
, , , , and are the coefficients of the model

and are dimensionless. The units of , , and are determined by both the unit system and the values of and , so that the equation is consistent.

This model is newer than SAE J1269 and provides more accuracy over a range of different vehicle loads (weight), tire pressures and vehicle speeds.[citation needed]

Fuel consumption

A 2003 California Energy Commission (CEC) preliminary study estimated that adoption of low-rolling resistance tires could save 1.5–4.5% of all gasoline consumption, but that current data were also insufficient to compare safety and other characteristics.[7]

A United States National Highway Traffic Safety Administration (NHTSA) study in 2009 found that if 2% of the replacement tires would reduce their rolling resistance by 5%, there would be 7.9 million gallons fuel and 76,000 metric tons of CO2 saved annually.[citation needed]

(SAE J1269 and SAE J2452) performed on new tires.

Standard equipment

Because fuel efficiency is an important selling point for most hybrid vehicles, they are often equipped with low-rolling resistance tires. Electric vehicles are also often equipped with low-rolling resistance tires to maximize their range.

Auto manufacturers in the United States typically equip new vehicles with tires that have lower rolling resistance than their average after-market replacements, in order to meet Corporate Average Fuel Economy (CAFE) standards.[8]

These include Conti Contact, Michelin Energy, Bridgestone Ecopia, and Goodyear Eagle LS tires. For Indian roads, Madras Rubber Factory(MRF) offers the MRF ZSLK range of eco-friendly car tires with low rolling resistance.[citation needed]

Available tires

Some tires available in 2003 ranked by coefficient from lowest (least wasteful), according to the United States National Academy of Sciences Transportation Research Board Special Report 286[2] and the March 2003 Green Seal report on the topic.[9]

  • 0.00615 Bridgestone B381 P145/80R14
  • 0.00650 Michelin SYMMETRY P225/60R16
  • 0.00683 Uniroyal TIGER PAW AWP P225/60R16
  • 0.00700 Bridgestone DUELER H/T 113S P265/70R17
  • 0.00709 BFGoodrich RUGGED TRAIL T/A P285/70R17
  • 0.00754 Michelin LTX A/S P255/65R17
  • 0.00758 Goodyear INTEGRITY (OE) P225/60R16
  • 0.00760 Bridgestone INSIGNIA SE 200 89S P195/65R15
  • 0.00767 BFGoodrich RUGGED TRAIL T/A P245/65R17
  • 0.00780 Continental Ameri-G4S WS P235/75R15
  • 0.00783 Continental CrossContact LX
  • 0.00795 Uniroyal TPAW TOURING TR/SR P215/70R16
  • 0.00810 Bridgestone DUELER H/T 104S P235/70R16
  • 0.00813 Goodyear Invicta GL 235/75R15
  • 0.00825 Continental ContiTouring Contact CH95 P205/55R16
  • 0.00829 Michelin CROSS TERRAIN SUV P255/75R17
  • 0.00833 Michelin PILOT PRIMACY 275/50R19
  • 0.00850 Michelin ENERGY LX4 P225/60R16
  • 0.00854 Michelin PILOT LTX P265/70R17
  • 0.00855 Michelin ENERGY MXV4 PLUS 235/65R17

Here is a list of Consumer Report's tires that achieved their best rolling resistance rating. The tires at the top of the list are rated higher overall.

  • Highly rated:
    • All Season
      • Michelin X Radial
      • Michelin Agility Touring
      • Michelin Harmony
      • Toyo 800 Ultra
      • Sumitomo HTR T4
  • Middle rank
    • Performance All Season
      • Michelin Energy MXV4 Plus
      • Continental ContiPremierContact H
  • Least benefit
    • All Season Ultra High Performance
      • General Exclaim UHP
      • Continental ContiExtremeContact

Below are the light duty tires (as reported by Consumer reports) achieving their best rolling resistance rating. Again, higher overall rated tires are closer to the top of the list.

  • All-season
    • Bridgestone Dueler H/T D684
    • Michelin Cross Terrain
    • Continental ContiTrac SUV
    • BFGoodrich Radial Long Trail T/A

Followed by:

  • All-terrain
    • Continental ContiTrac TR

New models by 2009:

  • Michelin Energy Saver
  • Goodyear Assurance Fuel Max

Comparison with conventional tires

Depending on the specific technique and materials used by the manufacturers, tire life may be as good as conventional tires, and traction may also be as good.[2]

A Transport Canada study that examined performance of vehicles that combined "light weighting" (reducing vehicle weight) and Low Rolling Resistance tires found that such vehicles performed about the same or better than their non-light-weighted/regular tire counterparts. The test vehicles were a Ford F150, rear-wheel drive standard pick-up truck; an Acura MDX, all-wheel drive sport-utility vehicle; and a Volkswagen Jetta, front-wheel drive compact sedan. Top speed and acceleration generally improved. "Handling performance showed no significant correlation with light-weighted and LRR tires; Braking & slalom testing showed variable results for the setups tested."[10]

A Union of Concerned Scientists newsletter says "LRR tires also meet the same federal standards for treadwear, traction, and temperature resistance as regular tires."[11]

Older Low-rolling resistance tires may reduce ability to grip, especially when taking corners, and may also wear out more rapidly.[12]

Regional requirements

California has rolling resistance requirements that went into effect in July 2008.[13] The law was passed in 2003 and the standards and reporting requirements were finalized in 2007.

United Nations require a regulation too: "Tire Rolling Sound Emissions, Adhesion on Wet Surfaces, and Rolling Resistance | UN Regulation No. 117".[14]

Certifications

Passenger tires are tested for rolling resistance in order to obtain the German Blue Angel eco-label[15]

See also

References

  1. ^ Low Rolling Resistance Tires (Website). Energy Efficiency and Renewable Energy, U.S. Department of Energy. Retrieved on 2007-08-11.
  2. ^ a b c "Tires and Passenger Vehicle Fuel Economy: Informing Consumers, Improving Performance -- Special Report 286.", National Academy of Sciences, Transportation Research Board, 2006. Retrieved on 2007-08-11
  3. ^ "Al Morrison Crr". Archived from the original on 2007-01-29.
  4. ^ California Energy Commission Archived 2012-03-10 at the Wayback Machine
  5. ^ 77 tires RRF Archived 2010-12-25 at the Wayback Machine
  6. ^ Transport Canada LRR Study Archived 2011-01-17 at the Wayback Machine
  7. ^ California State Fuel-Efficient Tire Report: Volume I California Energy Commission, July 2003. Retrieved on 2007-08-11.
  8. ^ Low Rolling Resistance Tires...Which is Best? - TDIClub Forums
  9. ^ Green Seal Report
  10. ^ "Dynamic Performance Comparison of Vehicle Models & New Model Generations Employing Lightweight Materials and Low Rolling Resistance Tires". Transport Canada (Government of Canada). Retrieved 7 July 2020.
  11. ^ Earthwise: Updates from the Union of Concerned Scientists, Volume 6, Number 2, Spring 2004 Archived 2008-01-15 at the Wayback Machine
  12. ^ "Rolling out the changes". The Economist. Dec 2, 2009. Retrieved 11 December 2009.
  13. ^ California has low-resistance tire laws - AutoblogGreen
  14. ^ "GAR | Tire Noise, Wet Adhesion, and Rolling Resistance". globalautoregs.com. Retrieved 2015-11-27.
  15. ^ Tires and Passenger Vehicle Fuel Economy: Informing Consumers, Improving Performance -- Special Report 286 (2006) by Board on Energy and Environmental Systems (BEES)

Read other articles:

Kolkata Municipal Corporation in West Bengal, IndiaWard No. 26Kolkata Municipal CorporationInteractive Map Outlining Ward No. 26Ward No. 26Location in KolkataCoordinates: 22°35′14″N 88°21′54″E / 22.58725°N 88.365028°E / 22.58725; 88.365028Country IndiaStateWest BengalCityKolkataNeighbourhoods coveredRamdulal Sarkar Street and Hedua ParkReservationOpenParliamentary constituencyKolkata UttarAssembly constituencyShyampukurBorough4Population (2011)&#...

 

 

الأسرة المصرية الخامسة والعشرون المدة؟ نظام الحكم غير محدّد التاريخ التأسيس 715 ق.م  التأسيس 715 ق.م  النهاية 656 ق.م  تعديل مصدري - تعديل   الأسرة الخامسة والعشرون لمصر، المعروفة أيضا باسم الأسرة النوبية أو الإمبراطورية الكوشية، كانت آخر أسرة حاكمة في الفترة المصرية ...

 

 

Kisah untuk GeriInggrisGeri's Story Genre Drama Roman Remaja BerdasarkanKisah untuk Gerioleh Erisca FebrianiSkenarioQueen B.SutradaraMonty TiwaPemeran Angga Yunanda Syifa Hadju Jennifer Coppen Elina Joerg Antonio Blanco Lagu pembukaTak Lagi Sendiri oleh AdivaLagu penutupCinta Hebat oleh Syifa Hadju feat Angga YunandaNegara asalIndonesiaBahasa asliBahasa IndonesiaJmlh. musim1Jmlh. episode9ProduksiProduser eksekutif Dhamoo Punjabi Jeff Han Kaichen Li Lesley Simpson ProduserManoj PunjabiSinemat...

Administrative division in some countries, managed by a local government For other uses, see District (disambiguation). This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: District – news · newspapers · books · scholar · JSTOR (June 2022) (Learn how and when to remove this template message) EkisticsShinjuku skys...

 

 

Grand Prix Tiongkok 2011 Lomba ke-3 dari 19 dalam Formula Satu musim 2011 Detail perlombaanTanggal 17 April 2011Nama resmi 2011 Formula 1 UBS Grand Prix TiongkokLokasi Shanghai International CircuitShanghai, TiongkokSirkuit Permanent racing facilityPanjang sirkuit 5.451 km (3.387 mi)Jarak tempuh 56 putaran, 305.066 km (189.559 mi)Posisi polePembalap Sebastian Vettel Red Bull-RenaultWaktu 1:33.706Putaran tercepatPembalap Mark Webber Red Bull-RenaultWaktu 1:38.993 putaran ke-42PodiumPertama Lew...

 

 

Cyclingat the Games of the IX OlympiadVenuesAmsterdam and surrounding areaAmsterdam Olympic StadiumDate4 –6 August 1928Competitors149 from 27 nations← 19241932 → The cycling competition at the 1928 Summer Olympics in Amsterdam consisted of two road cycling events and four track cycling events, all for men only.[1] The individual event in road cycling was a time trial over a distance of 168 km; the team competition was decided by aggregating...

Questa voce sull'argomento cestisti statunitensi è solo un abbozzo. Contribuisci a migliorarla secondo le convenzioni di Wikipedia. Segui i suggerimenti del progetto di riferimento. André Roberson André Roberson con la maglia degli Oklahoma City Thunder Nazionalità  Stati Uniti Altezza 201 cm Peso 95 kg Pallacanestro Ruolo Guardia / Ala piccola Squadra Template:Basket Strong Group Athletics Carriera Giovanili ?-2010Wagner High School2010-2013 Colorado Buffaloes Squadre di ...

 

 

United States historic placeGraham CaveU.S. National Register of Historic PlacesU.S. National Historic Landmark Show map of MissouriShow map of the United StatesLocationMontgomery County, Missouri, United StatesNearest cityMineola, MissouriCoordinates38°54′19″N 91°34′23″W / 38.90528°N 91.57306°W / 38.90528; -91.57306NRHP reference No.66000420Significant datesAdded to NRHPOctober 15, 1966[1]Designated NHLJanuary 20, 1961[2] Gr...

 

 

American politician Chapman FreemanMember of the U.S. House of Representativesfrom Pennsylvania's 1st districtIn officeMarch 4, 1875 – March 3, 1879Preceded bySamuel J. RandallSucceeded byHenry H. Bingham Personal detailsBornNathaniel Chapman Freeman(1832-10-08)October 8, 1832Philadelphia, Pennsylvania, U.S.DiedMarch 22, 1904(1904-03-22) (aged 71)Strafford, Pennsylvania, U.S.Political partyRepublican Chapman Freeman (October 8, 1832 – March 22, 1904) was a Republ...

Peugeot 106InformasiProdusenPeugeotMasa produksi1991–2003 (2,798,200 unit)PerakitanMulhouse, PrancisAulnay-sous-Bois, PrancisLa Marsa, Tunisia (STAFIM)Bodi & rangkaKelasSupermini (B) (1991-1998)Mobil kota (A) (1998-2003)Bentuk kerangka3-pintu hatchback5-pintu hatchbackTata letakFront-engine, front-wheel-driveMobil terkaitCitroën SaxoPenyalur dayaMesinbensin:954 cc TU9 I41124 cc TU1 I41294 cc TU2 I41360 cc TU3 I41587 cc TU5 I4diesel:1360 cc TUD3 I41527...

 

 

Pour la base navale, voir Base navale de Pearl Harbor. Pour l’attaque, voir Attaque de Pearl Harbor. Pour les autres significations, voir Pearl Harbor (homonymie). Pearl Harbor Image satellite de Pearl Harbor. Géographie humaine Pays côtiers États-Unis Subdivisionsterritoriales Hawaï Ponts Ford Island Bridge Géographie physique Type baie Localisation Océan Pacifique Coordonnées 21° 21′ 43″ nord, 157° 57′ 13″ ouest Subdivisions West Loch, Middl...

 

 

2016年美國總統選舉 ← 2012 2016年11月8日 2020 → 538個選舉人團席位獲勝需270票民意調查投票率55.7%[1][2] ▲ 0.8 %   获提名人 唐納·川普 希拉莉·克林頓 政党 共和黨 民主党 家鄉州 紐約州 紐約州 竞选搭档 迈克·彭斯 蒂姆·凱恩 选举人票 304[3][4][註 1] 227[5] 胜出州/省 30 + 緬-2 20 + DC 民選得票 62,984,828[6] 65,853,514[6]...

2020年夏季奥林匹克运动会波兰代表團波兰国旗IOC編碼POLNOC波蘭奧林匹克委員會網站olimpijski.pl(英文)(波兰文)2020年夏季奥林匹克运动会(東京)2021年7月23日至8月8日(受2019冠状病毒病疫情影响推迟,但仍保留原定名称)運動員206參賽項目24个大项旗手开幕式:帕维尔·科热尼奥夫斯基(游泳)和马娅·沃什乔夫斯卡(自行车)[1]闭幕式:卡罗利娜·纳亚(皮划艇)&#...

 

 

Rachel Carson Información personalNombre en inglés Rachel Louise Carson Nacimiento 27 de mayo de 1907 Rachel Carson Homestead (Springdale, Estados Unidos) Fallecimiento 14 de abril de 1964 Silver Spring (Estados Unidos) Causa de muerte Cáncer de mama e infarto agudo de miocardio Sepultura Parklawn Memorial Park Residencia Silver Spring Nacionalidad EstadounidenseEducaciónEducada en Chatham University (1925-1929)Universidad Johns Hopkins (M.A.; 1929-1932) Información profesional...

 

 

Oceanian university headquartered in Suva, Fiji The University of the South PacificOceania Centre for Arts, Culture & Pacific Studies in SuvaTypePublicEstablished1968; 56 years ago (1968)ChancellorDavid VunagiVice-ChancellorPal AhluwaliaAcademic staff400[1]: 22 Administrative staff1,114[1]: 22 Students29,918 (2017)[1]: 17 Undergraduates16,721(2017)[1]: 17 Postgraduates2,933 (2...

American actress For the Canadian ballet dancer, see Lois Smith (dancer). For the American entertainment publicist, see Lois Smith (publicist). Lois SmithSmith in 2017BornLois Arlene Humbert (1930-11-03) November 3, 1930 (age 93)Topeka, Kansas, U.S.OccupationActressYears active1952–presentSpouse Wesley Smith ​ ​(m. 1948; div. 1970)​Children1 Lois Arlene Smith (née Humbert; born November 3, 1930) is an American character actress whos...

 

 

Grand Prix Republik ArgentinaGrand Prix Sepeda MotorTempatAutódromo Termas de Río HondoLomba pertama1960Terbanyak menang(pengendara)Hugh Anderson, Mick Doohan, Tom Phillis (3)Terbanyak menang(pabrikan)Honda (12) Grand Prix Sepeda Motor Argentina merupakan seri dari kejuaraan balap FIM Grand Prix Sepeda Motor. Acara ini telah diadakan sepuluh kali di Autódromo Oscar Alfredo Gálvez antara musim 1961 dan 1999. Grand Prix Argentina kembali menjadi tuan rumah penyelenggaraan MotoGP pada musim ...

 

 

Gwen TorrenceNazionalità Stati Uniti Altezza170 cm Peso57 kg Atletica leggera SpecialitàVelocità SocietàAthletics WestMazda Optimists Track ClubNike Record 60 m 702 (indoor - 1996) 100 m 1082 (1994-1996) 200 m 2172 (1992) 200 m 2233 (indoor - 1996) 400 m 4964 (1992) CarrieraNazionale 1985-1996 Stati Uniti Palmarès Competizione Ori Argenti Bronzi Giochi olimpici 3 1 1 Mondiali 3 4 1 Mondiali indoor 0 1 0 Giochi panamericani 2 0 0 Universiadi 3 0 0 Vedi maggiori dettagli  Modific...

Disambiguazione – Mignano rimanda qui. Se stai cercando altri significati, vedi Mignano (disambigua). Questa voce o sezione sull'argomento centri abitati della Campania non cita le fonti necessarie o quelle presenti sono insufficienti. Puoi migliorare questa voce aggiungendo citazioni da fonti attendibili secondo le linee guida sull'uso delle fonti. Mignano Monte Lungocomune LocalizzazioneStato Italia Regione Campania Provincia Caserta AmministrazioneSindacoAndrea...

 

 

  提示:此条目页的主题不是埃伯哈德二世 (符騰堡公爵)。 埃伯哈德二世(德語:Eberhard II.,約1320年—1392年3月15日),烏爾里希三世的長子,符騰堡伯爵(1344年—1392年)。埃伯哈德二世在位期間符騰堡領地擴張至門根、伯布林根等城鎮。他的兒子烏爾里希早於他去世,由孫子埃伯哈德三世繼位。 埃伯哈德二世 参考文献 Das Haus Württemberg - Ein biographisches Lexikon, 1997, W....