# Heat produced from Brake Pad Friction material?

1. Feb 21, 2007

### heiroglif

Hi all,

My model of a car brake system is intended to monitor the rate at which heat increases/decreases as friction between a brake pad and disc increases.

My equation for the force transmitted to the disc is:

Force = (δP x Ac) x μb

where δP is the pressure generated at the master cylinders

Ac is the area of the caliper pistons

and μb is the coefficient of friction of the brake pad material.

how can i find the heat generated fromt his equation, any suggestions?

2. Feb 21, 2007

### grant9076

I am no expert but the brakes convert kinetic energy into heat. So if you know the car's velocity and mass, you can figure out how much kinetic energy will be converted to heat.

Also, if you know how much force the brake is applying and the distance over which it is applied, you can figure out how much energy was converted to heat.

3. Feb 22, 2007

### haiha

Now that you know the force F. Just imagine the car is in its stop and you still push the brake: no heat. The work is calculated as : W=FS , then dW=FdS <==> dW/dt=FdS/dt (S is the distance, v: velocity) or power P=Fv. All the work is converted into heat so with that equation, you calculate exactly the heat generated by the brake.
You can also easily compute the heat by : E=mv^2/2. But the mass in this equation is not fix, and the energy E also includes the friction caused by air drag.

4. Feb 22, 2007

### heiroglif

Guys thanks alot for your replies, its much appreciated, i will study what you have said, and if i have any more issues, will post them here....thanks :)