Enter the heat flux, brake on time, density of disc material, specific heat capacity, thermal conductivity, and ambient temperature into the calculator to determine the maximum brake disc temperature.

Brake Disc Temperature Formula

The following equation is used to calculate the maximum Brake Disc Temperature.

BDTm = (0.527 * q * Sqrt (t)) / Sqrt(p*c*k) + Tamb

  • Where BDTm is the maximum Brake Disc Temperature (C)
  • q is the heat flux (watts/m^2)
  • t is the brake on time (s)
  • p is the density of the brake disc (kg/m^3)
  • c is the brake disc specific heat capacity (J/kg/K)
  • k is the brake disc thermal conductivity (W/(m*K))
  • Tamb is the ambient temperature (C)

What is a Brake Disc Temperature?


A Brake Disc Temperature is often considered the maximum temperature that a brake will reach given the inputs above.

How to calculate Brake Disc Temperature?

Example Problem:

The following example outlines how to calculate a brake disc temperature.

First, determine the heat flux. In this case, the heat flux is 10000 watts/m^2.

Next, determine the brake on time. These brakes are on for 5 seconds.

Next, determine the density of the disc. This disc has a density of 7000 kg/m^3.

Next, determine the specific heat of the disc. This is found to be 500 J/kg/K.

Next, determine the thermal conductivity of the brake. This averages 58 W/(m*k) for cast iron.

Next, determine the ambient temperature. The ambient temperature if 40C.

Finally, calculate the Brake Disc Temperature using the formula above:

BDTm = (0.527 * q * Sqrt (t)) / Sqrt(p*c*k) + Tamb

BDTm = (0.527 * 10000 * Sqrt (5)) / Sqrt(7000*500*58) + 40

BDTm = 40.82 C