What is the speed of the fan in rpm if it is driven by a motor with a 90 mm pulley rotating at 1,800 rpm and a fan shaft pulley of 300 mm?

To determine the speed of the fan in revolutions per minute (rpm), you can use the relationship between the pulley sizes and the speed of the motor.

The formula that relates the speeds and diameters of two pulleys connected by a belt is as follows:

[

\frac{N_1}{N_2} = \frac{D_2}{D_1}

]

Where:

• (N_1) is the speed of the first pulley (motor pulley),

• (N_2) is the speed of the second pulley (fan pulley),

• (D_1) is the diameter of the first pulley (motor pulley),

• (D_2) is the diameter of the second pulley (fan pulley).

In this scenario:

• The motor pulley has a diameter of 90 mm and rotates at 1,800 rpm.

• The fan pulley has a diameter of 300 mm.

Plugging in the values, we get:

[

\frac{1,800 , \text{rpm}}{N_2} = \frac{300 , \text{mm}}{90 , \text{mm}}

]

Calculating the diameter ratio:

[

\