I in solving temperature rise in Brake rotors.

Click For Summary

Discussion Overview

The discussion centers around calculating the mean temperature increase of brake rotors when a vehicle comes to a stop, specifically focusing on the energy transfer from braking to heat in the rotors. The scope includes theoretical calculations and assumptions regarding physical properties of the rotors.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant proposes calculating the mass of the rotors and the energy absorbed to determine the temperature rise using specific heat, suggesting a straightforward method.
  • Another participant questions the validity of the rotor diameter of 3mm, implying it may be an error due to its small size.
  • Repeated assumptions about the rotor's dimensions, density, specific heat, and thermal conductivity are presented, indicating a need for clarity on these parameters.
  • A reminder is issued regarding forum rules, emphasizing the necessity for participants to show their efforts before receiving tutorial help.

Areas of Agreement / Disagreement

Participants do not appear to reach consensus on the rotor diameter, with at least one participant expressing skepticism about the provided measurement. The discussion remains unresolved regarding the implications of this dimension on the calculations.

Contextual Notes

The discussion includes assumptions about the physical properties of the rotors, which may not be universally applicable. The diameter of the rotor is particularly contentious and may affect the calculations significantly.

akki2063
Messages
2
Reaction score
0
If we assume 70% of braked energy from the previous case is transferred to heat into two front brake rotors.How much would the mean temperature of front rotor increase when the vehicle is put to stop.

Assume that :
1)rotor's diameter is 3mm.
2)rotor's thickness is 1cm.
3)Density : 7800 kg/m^3.
4)Specific heat (Cp) : 500 J/Kg K.
5)Thermal conductivity (K) : W/mK.
 
Physics news on Phys.org
Diameter 3mm?

The simple method:

Figure out the mass.

Figure out the energy absorbed in J

Work out the temp rise from the specific heat. I.e 500KJ into 1kg = 1000°K
 
akki2063 said:
If we assume 70% of braked energy from the previous case is transferred to heat into two front brake rotors.How much would the mean temperature of front rotor increase when the vehicle is put to stop.

Assume that :
1)rotor's diameter is 3mm.
2)rotor's thickness is 1cm.
3)Density : 7800 kg/m^3.
4)Specific heat (Cp) : 500 J/Kg K.
5)Thermal conductivity (K) : W/mK.

Check your PMs. You *must* show your efforts before we can provide tutorial help. That is in the PF Rules (see the top of the page under Site Info).
 
A rotor diameter of 3mm is almost microscopic. Are you sure this dimension is correct?
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
7
Views
2K
  • · Replies 2 ·
Replies
2
Views
5K
Replies
7
Views
2K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
1
Views
3K
Replies
9
Views
4K
Replies
13
Views
3K