As a result, the maximum relative airflow must be constrained to 1.
Equation 22 can be used to determine the required fan settings for a given total relative airflow. However, first it is necessary to have specific sequencing rules for the order in which fans should be turned on and off.
The conversion process between a relative airflow setpoint and the discrete fan control involves choosing the set of discrete fan settings from the table that produces a tower airflow closest to the desired flow, assuming that airflow is proportional to fan speed.
According to Equation 22, the fan-speed setting if all cells are operating is equal to the relative airflow setpoint.