Quote:
Originally Posted by 8cd03gro
Loss to heat as a percentage of power output decreases as power increases because inertia of the drivetrain and friction remain the same regardless of power output.
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Heat is a result of friction. Friction does not remain the same regardless of power output (see my previous post), but does go down as a percentage as power increases. So loss to heat as a percentage does go down, but not due to inertia and not because friction stays the same.
Quote:
Originally Posted by 8cd03gro
Let's say I is the force required to overcome the inertia of the drivetrain, it is a constant. Y is the total power output of the engine and X is the power at the wheels. Just for simplicity we will assume a 12% loss due to variables other than inertia. In this oversimplified example the function of total power output to determine wheel hp would be
X = 0.88Y-I
As Y increases, I remains the same. So, let's say I is 10hp, and Y is 400hp.
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I is not measured in HP. I (inertia) for driveline purposes is the equivalent of a rotational mass. And like any mass (in the absence of friction or other external forces), it doesn't take any force to keep it moving at a constant speed. But it does take force (or torque for rotational purposes) to accelerate. If you want to know what it takes to accelerate a given rotational inertia to a given speed (i.e. RPM), then that is measured in work. How quickly you increase that inertia to that rotational speed (i.e. acceleration) can be measured in power (i.e. HP)