Estimating Tire Pressure Based on Different Tire Temperature Measurement Points

Knowing the tire pressure during driving is essential since it affects multiple tire properties such as rolling resistance, uneven wear, and how prone the tire is to tire bursts. Tire temperature and cavity pressure are closely tied to each other; a change in tire temperature will cause an alteration in tire cavity pressure. This article gives insights into which tire temperature measurement position is representative enough to estimate pressure changes inside the tire, and whether the pressure changes can be assumed to be nearly isochoric. Climate wind tunnel and road measurements were conducted where tire pressure and temperature at the tire inner liner, the tire shoulder, and the tread surface were monitored. The measurements show that tires do not have a uniform temperature distribution. The ideal gas law is used to estimate the tire pressure from the measured temperatures. The results indicate that of the compared temperature points, the inner liner temperature is the most accurate for estimating tire pressure changes (average error 0.63%), and the pressure changes during driving are nearly isochoric. This conclusion can be drawn because the ratio between inner liner temperature and tire pressure is nearly constant, and the pressure can be simulated well using the isochoric gas law.