03-09-2012, 03:15 PM
HEAT TRANSFER PHENOMENA IN A DISC BRAKES AND ANALYSIS OF HOTSPOTS USING FEM
disc brakes M.TECH CADCAM-ppts.pptx (Size: 4.05 MB / Downloads: 92)
INTRODUCTION:
Heat transfer in brakes influences strongly their efficiency.
The friction coefficient of the brake lining drops off quickly with temperature, reducing the braking efficiency.
The heat generated in brakes may lead to brake fluid vaporization ending up with loss of braking action.
The hot spots are caused by poor heat dissipation and high spots on the rotor surface .
These high spots are usually caused by wrapping due to concentrated thermal stresses because of non-uniform contact.
Hence understanding of heat transfer phenomena and hotspots is important.
EXPERIMENTATION:
Commonly used cast iron disc brake is first tested.
With the help of an infrared thermometer the temperatures of disc brake at different positions for different speeds are measured.
The heat transfer coefficient of the existing disc brake is then calculated from existing formulas.
Analytical calculations of other materials are also done.
FEM ANALYSIS:
FEM analysis will be performed in ANSYS.
The thermal analysis will be performed on the brake disc to find the stress distribution.
Both 2-D model and 3-D model will be tested to predict the hot spot formation.
Also a coupled thermo-mechanical analysis will be performed to predict the formation of hot spots more accurately.
The simulation results for all models and materials will be collected and analysed.