According to fan law, how many times the speed is needed to develop twice the volume?

The correct answer is that it requires twice the speed to develop twice the volume of airflow. This is rooted in fan law, specifically the relationship between airflow (volume), speed (rpm), and pressure.

According to fan laws, when considering the effect of fan speed on airflow volume, it is established that airflow volume is directly proportional to the fan speed raised to the cube. To put it mathematically, if airflow (Q) is proportional to the speed (N), we express this as Q ∝ N³. This means that if you want to double the airflow volume, you need to increase the speed of the fan significantly.

This can be understood through the formula: Q1/Q2 = (N1/N2)³ where Q represents airflow and N represents speed. By applying this formula, if you set Q2 to be double Q1 (2Q1), then:

2Q1/Q1 = (N1/N2)³ implies that 2 = (N1/N2)³.

To solve for the ratio N1/N2, you take the cube root of both sides, yielding N1/N2 = 2^(1/3), which approximately results in a factor of 1.26. To