1998-09-20

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.

SAE MOBILUS

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

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Relationship of the Transfer Film Formed Under Low Pressure Drag Conditions and Torque Variation

982255

View Details

TECHNICAL PAPER

High-Precision Brake Discs to Reduce Judder

2005-01-3924

View Details

TECHNICAL PAPER

FE Prediction of Thermal Performance and Stresses in a Disc Brake System

2006-01-3558

View Details

X