Rolling resistance of tires

FE simulations of the stress-strain properties of fiUer-reinforced elastomers are an important tool for predicting the service live performance of mbber goods. Typical examples are the evaluation of rolling resistance of tires due to hysteresis energy losses, mainly in the tire tread or the adjustment of engine mounts in automotive applications. 

The rolling resistance of tires made from NR or SBR is reduced by the presence of increasing amounts of BR. This reduces the fuel consumption of vehicles on the road. However, the presence of BR gives rise to poor wet traction, but the presence of about 40 percent (of the polymer) BR gives improvements in ice traction. In addition, BR has a great tolerance for high levels of extender oil and carhon black. 

The tan 6 measured by our Instrumented Yerzley Oscillograph (abbreviated as lYO) has adequate precision, and was found to correlate reasonably well with tan 6 measured on rubber samples by the MTS equipment at 40 Hz and 60 C. It also correlates remarkably well with rolling resistance of tires (Figure 11) as determined by the "Twin Roll Method" and used for evaluation and testing of tires. 

In silicarfilled styrene-butadiene rubbers, due to weak polymer-filler interactions, the silica network is highly developed (Figm-e 4.7c). The use of a coupling agent improves the dispersion and consequently reduces substantially the amplitude of the Payne effect and also tg 6, which is an important parameter in the rolling resistance of tires. 

From this figure, we see that the rolling resistance of a tire can not be reduced too much without regard to the effect on the formation of standing wave. 

To reduce the rolling resistance of automobile tires and improve their wet nonskid properties at the same time, the carbon black in the tire formula is replaced by active silicic acid with added organosilane. 

The WET p and Tan 8 were measured in the evaluation of a rubber compound as the tread rubber of tire for the various rubber compounds containing the different tackifiers at the same level of 2.5 phr. The WET p, evaluated by a flat-belt type friction tester, refers to the coeflbcient of friction between the wet surfaces, and would reflect the tire performance in road gripping under wet conditions. On the other hand, the Tan 6 would be related to the rolling resistance of the tire compound and was measured by viscoelasticity tester. In general, as shown in Table... 

Soon after vinyl BR s were first introduced commercially, it was recognized that the vinyl structure imparted non-typical dynamic properties. In particular, their vulcanizates showed improved resistance to heat build-up when compared to emulsion SBR. j O Before relating the special contribution of the vinyl structure to properties, it is informative to first determine the influence of styrene content (at constant vinyl) on the two fundamental properties of interest Tg and tan 6, as shown in Figure 14. As expected, both Tg and tan 6 increase almost linearly with styrene content. Thus like a conventional tire tread rubber, the rolling resistance of solution SBR s prepared using lower amounts of styrene is accompanied by a decrease in the wet traction of the rubber. 

Gillespie, T. D. 1992. Fundamentals of Vehicle Dynamics. Warrendale, PA Society of Automotive Engineers. Explains the performance of an automotive vehicle, with chapters focusing on acceleration performance, braking performance, aerodynamics and rolling resistance, ride, tires, steady-state cornering, suspensions, steering systems, and roll-over. 

One of the original uses for precipitated hydrated silica was its use in the original HRH adhesion compounds. Even though silica is also used today as a very important inorganic filler to improve rolling resistance in tire tread compounds, it is still used extensively in the wire coat or breaker compounds to impart steel tire cord adhesion. 

Region related with rolling resistance of a tire -J ... 

Guanidines. Guanidines (10) were one of the first aniline derivatives used as accelerators. They are formed by reaction of two moles of an aromatic amine with one mole of cyanogen chloride. Diphenylguanidine (DPG) has enjoyed a resurgence ia demand as an activator for sulfenamides and a co-accelerator ia tire tread compounds which employ siUca fillers for low rolling resistance. Guanidines alone show too Htde activity to be extensively used as primary accelerators. There were no U.S. producers as of mid-1996. 

The tread is desigaed and compounded for abrasion resistance, traction, low rolling resistance, and protection of the carcass. It often is divided iato two subcomponents to maximize performance the outer tread for surface contact, and the undertread for tying iato the carcass while reduciag tire rolling resistance through decreased hysteresis. 

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