What is gd2 value for a motor?

# 1 gd2 is the value which is meant to check that whether a

given motor will mingle with an impeller or not. Its a

sought of age of fan and motor.

Technically , it tells us about the measure of the ability

of the motor to attain its a rated speed from rest.

This is calculated with the formula

4 x m x r2

m = mass of the impeller

r = radius of gyration

r shall be 0.4 times the radius of impeller

I hope its sought of clear now