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A novel reinforcement structure in tire tread compounds
Published in Alexander Lion, Michael Johlitz, Constitutive Models for Rubber X, 2017
W.R. Córdova, J.G. Meier, D. Julve, M. Martínez, J. Pérez
The cost-effective manufacture of low rolling resistance tires is one of the most important development goals in tire industry today. In this context, a European study projects that a 3% reduction in fuel consumption with the use of low rolling resistance tires can lead to a reduction in global well-to-wheels greenhouse gas emissions by 100 million metric tons per year by 2020 (Kodjak, 2015; Pike & others, 2011). The use of swollen synthetic laminar silicate as an additive in tire tread compounds can provide significant benefits in mechanical properties, rolling resistance and ice/wet grip in comparison with normal HDS compounds (J. G. Meier, 2013b, 2015). The aforementioned papers report the results of a normal tire tread compound additivated with 3phr of organo-modified synthetic layer silicate. An improvement in the rolling resistance predictor (tan δ-value at 60°C) of ca. 35% was obtained for 3phr OCTO-CTA compounds. Furthermore, the ice/wet grip predictor (tan δ-value at ≈ −20°C) was also improved, while volume loss or abrasion was not affected. Tensile tests at room temperature also showed higher stress at break for the additivated compounds than the reference silica-only compounds. However, in the same test, at small elongations up to 100%, the stresses are lower for additivated compounds (c.f. Figure 1). Additionally, vulcanization rate was found to be accelerated in the additivated compound. This effect was considered to be related to the accelerating effect the organic surfactant can have at the typical rubber process temperatures of between 150–170°C (Galimberti Maurizio, 2009), which releases the organic modifier during the exfoliation process. However, the natural analogue reference, MMT-CTA (organo-modified montmorillonite), did not show that effect (J. G. Meier, 2013a, 2013b, 2015). The rise in vulcanization rate can reduce the cost of manufacturing low-rolling resistance tires in a production process. In addition, the accelerated vulcanization rate can be used as a quality control of successful exfoliation.
Tire Testing and Performance
Published in Brendan Rodgers, Tire Engineering, 2020
The conversion to radial tires has had the largest impact on fuel savings and is why the trend toward radialization continues (Figure 10.18). Substantial savings are possible by installing and maintaining energy-efficient low-rolling-resistance tires.
Deriving fuel-based emission factor thresholds to interpret heavy-duty vehicle roadside plume measurements
Published in Journal of the Air & Waste Management Association, 2018
David C. Quiros, Jeremy D. Smith, Walter A. Ham, William H. Robertson, Tao Huai, Alberto Ayala, Shaohua Hu
Vehicles A, B, and C were tested at CARB’s Depot Park Facility located in Sacramento, CA. The laboratory is equipped with a single-roll 72-inch, 600-hp chassis dynamometer manufactured by Burke E. Porter Machinery Company (model 4700, Grand Rapids, MI) designed to simulate road loads on vehicles with GVWR between 10,000 and 80,000 lb. The MHD and HHD vehicles tested in the laboratory were tested at 80% of their respective GVWRs, which were 26,500 lb for vehicle A and 65,000 lb for vehicles B and C. Drive axle inertia was set to 1.5%. Target road loads were derived following guidelines in SAE J1263 and J2263. Vehicle A was a box truck configuration, and road load targets were 160.59 lbsf, −0.883 lbsf/(mph), and 0.1781 lbsf/(mph); vehicles B and C were dual-axle sleeper cab tractors; coast-downs were performed with a 50-foot trailer with low rolling resistance tires, and road load targets were 268.08 lbsf, 6.605 lbsf/(mph) 0.1001 lbsf/(mph).
Reducing the ecological footprint of urban cars
Published in International Journal of Sustainable Transportation, 2018
Bonnie McBain, Manfred Lenzen, Glenn Albrecht, Mathis Wackernagel
The emission factors relating to fuel mix (Section 2.1.6) were adjusted to account for technological improvements in car transport efficiency other than those related to fuel mix and engine type. Such efficiency improvements could include factors such as body design and aerodynamics, lightweight materials, continuously variable transmission, advanced low rolling resistance tires, improved exhaust treatment, and improved combustion technology (Turton, 2006). Other factors affecting efficiency include car size and power; however, as noted by Turton (2006), the response of these particular factors to increases in affluence tends to counteract improvements in vehicle efficiency. Therefore, overall vehicle efficiency improvements must account for both technological improvements and trends that counter them. A review of the literature by Turton (2006) with these considerations in mind concluded that average fuel consumption rates under moderate long-term technological gains (e.g. SRES B2) could conservatively reduce emissions at 2% per decade till 2100 (or a total of 20% reduced fuel use).
Enhancing near-road exposure assessment
Published in Journal of the Air & Waste Management Association, 2021
Petros Koutrakis, Dan Greenbaum
Non-tailpipe particle mass (PM) emissions are formed mostly from mechanical processes, in contrast with particles from tailpipe emissions, which are formed during fuel combustion. Because of the significant reduction of tailpipe PM emissions from new technology vehicles, interest in non-tailpipe emissions of motor vehicles is increasing. The main sources of non-tailpipe PM emissions from on-road vehicles include as follows: generation by abrasion of brakes and tires, generation by abrasion of the road surface, and re-suspension from the road surface (called road dust). Particles from non-tailpipe sources differ from those associated with tailpipe emissions in both composition and size distribution. Their size is generally larger than tailpipe particles, although such particles have less carbonaceous material and a higher metallic content (Liati et al. 2019; Nosko, Vanhanen, and Olofsson 2017). Specific chemical species considered to be tracers of non-tailpipe emissions include barium (Ba), copper (Cu), antimony (Sb), iron (Fe), and zinc (Zn) that are derived mostly from brake lining, pads, and rotors, as well as Zn and benzothiazoles for tire wear emissions (Grigoratos and Martini 2015; Denier van der Gon et al. 2013). Study of non-exhaust emissions is challenging because the composition of brakes and tires is highly variable, generally proprietary, constantly changing, and differs by application (e.g., light vs. heavy duty vehicles, traditional vs. low rolling resistance tires, new vs. retreaded tires). For example, Cu and certain other components are being phased out of brake pads as the result of a Memorandum of Understanding among the United States Environmental Protection Agency and various affiliated industry organizations (US EPA 2015). Furthermore, the composition of materials used to build roads, their wear, and the dispersal of dust from surrounding areas is variable.