Air Volume/Velocity Overview
(Data covered in this post is highlighted inside the green rectangle)
The Total Air Volume in cubic feet is the total amount of air volume the fan ventilates for the entire production time.
The Average Main Duct Velocity is the velocity measured in the main duct right before it enters the fan. This value needs to be above the minimum transport air velocity in order to avoid sawdust settling (this value is determined based on material transported).
The Average Main Duct Air Volume (in CFM) is the average working air volume the system ventilates (based on the average velocity value).
Air Volume (CFM) = Air Velocity (FPM) x Area of Main Duct (sq feet).
How to read the data
You could use the total amount of air volume to predict how frequently you have to change the trailer bin (that contains sawdust). You could also use the number as a comparison to the past to see how long the trailer bin usually gets full. For example, you notice that it takes around 200,000,000 cubic feet of air volume for the bin to be full. And Total Air Volume per day is around 45,000,000 cubic feet. You can now estimate that between 4 to 5 days, you will need to change the bin.
Average main duct velocity is critical. This value should not be lower than minimum transport air velocity to avoid sawdust settling inside the duct system. If you notice that this number drops over an extended period of time, this could indicate that the filter is getting dirtier and might need to be replaced for better performance.
Average Main Duct Air Volume mainly depends on the workstation utilization. Daily data on average main duct air volume should stay consistent over time (if production rate doesn’t change rapidly).
Monitor the main duct velocity to make sure the value doesn’t decrease over time, and that the value doesn't fall below minimum transport air velocity to avoid dust settling.
Try to compare average main duct air volume with the value stated from the preliminary estimate or working air volume from the engineering report. This number can be used to fine-tune the system. If we know the total design Air Volume (in CFM) of the whole entire system and a good utilization percentage data from our server, we could try to compare this value with the working air volume to fine-tune the system and even greatly reduce the electricity consumption.
This article is part of a sequence: Ecogate's Daily Analytics Report. Click Here to start from the top of the sequence.
Authors: Thanh Vu, Ales Litomisky