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Old 2nd Nov 2001, 18:44
  #20 (permalink)  
RatherBeFlying
 
Join Date: Sep 2001
Location: Toronto
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Moggie, I'm not sure that reduced final brake temperature when heavy braking is applied is solely due to reduced tire flex -- mind you I don't have the numbers.

Speculating, I can conjure up two other mechanisms:
  • Reduced time the brake pucks are held against the disks at low efficiency
  • Increased erosion of high temperature particles

A brake disk erodes and loses mass with successive braking applications. A maximum effort stop from a given speed at the same weight and other conditions will produce a lower final temperature on a new disk than on a thinner disk near the end of its useful life.

For that I can offer an equation:

T = mEc

Where:
  • T - Temperature increase
  • m - Mass
  • E - Energy Transfer to disk
  • c- Heating coefficient of brake disk material, i.e. Temperature increase of unit mass of brake disk material per heat energy unit input
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