How it works

Drying, cooling and maintenance
There are three different types of aeration: drying, cooling and maintenance. To date this has never been combined in one controller, but the Aeration Manager™ has changed all that as it not only combines all three functions in one controller but automatically selects the correct type of aeration out of the three.

Air selection
With other aeration controllers, the activation of the fans is based on a combination of time functions and ambient air conditions. This rarely takes in the condition of the grain as a point of control. With the Aeration Manager™ the status (temp and moisture) of the stored grain is derived from data entered during inload and from weather station data during fan run hours. This predictive technology is the heart of the system and allows the controller to take the grain condition into consideration when activating the fan(s). This will therefore only turn on the fan(s) when the grain requires airflow.

Adaptive Discounting
Without knowing what has been achieved to date with regard to drying or cooling the grain, it would be possible to inject air into the silo that could have an adverse effect on the grain even though that air may fall within the boundaries of selected air. For example, if the air managed to cool the grain to say 20ºC (down from 30ºC), and the inlet air selection was based on air below 30ºC, 25ºC air will actually warm the grain again.  The same applies to drying. This is what the CSIRO calls adaptive discounting, and importantly this is achieved without the use of in-store sensors.

In process control terminology this is called setpoint control, where the process variable (the actual grain moisture or temperature) is compared with the setpoint and the available drying or cooling capacity of the ambient air to achieve its desired outcome. The calculated grain temperature or moisture is therefore called calculated process variable and abbreviated to CPV in the diagnostic pages of the controller.
 
Use of the Buffer Area
The grain around the inlet air section of the silo is called the buffer area. This Aeration Manager™ technology allows for the buffer area within a silo (approx one hour's worth of aeration) to act as a filter for air that would normally fall outside the standard limits (too moist or too warm). For example when the controller has determined that the buffer area will be capable of absorbing some moist air, cool moist air will allow the rapid cooling of the grain mass. This way the air that would normally have been discarded as too moist will be put to good use. The same applies to warm dry air when the buffer area can absorb some heat.

Running cost
The result of this selective fan control (adaptive discounting and the use of the buffer area) means a substantial reduction in fan run hours and hence operating costs. Optional monitoring of the fancurrent by the controller will also ensure that an alarm will be created when the fan fails, thereby increasing the reliability of the system.
 
Operation
The entry of data into the Aeration Manager™ has been made simple through the use of ATM-type touch screens that guide you through the various functions of the controller. Overview screens ensure that the current grain condition of all eight silos can easily be accessed.