A Dynamometer Investigation of Thermal Judder 982252

Thermal judder occurs when differential thermal expansion is experienced around the rotor during a brake application. A temporary circumferential disc thickness variation (DTV) is created which can lead to brake torque variation. The cause of the uneven heating of the rotor can be an imperfection; often a permanent DTV caused by periods of off-brakes contact between pad and disc. Using a dynamometer test combining dynamic disc thickness measurement and pyrometric techniques the evolution of thermal DTV may be studied. It can be demonstrated that increasing thermal DTV is accompanied by increasing brake torque variation. Hot spot formation is also evident but this is shown not be the primary cause of brake torque variation.


Subscribers can view annotate, and download all of SAE's content. Learn More »


Members save up to 40% off list price.
Login to see discount.
Special Offer: With TechSelect, you decide what SAE Technical Papers you need, when you need them, and how much you want to pay.