While harvesting wet corn this year I had a problem with an excessive amount of fines in my sample. So I installed a screen under the clean grain auger instead of a solid trough. But I didn't know for sure what effect that might have on the amount if air blowing up through the shoe and chaffer. Sitting still with the Separator running I got out and it actually felt as if air were being drawn into the screen, like the velocity of the air coming off the fan was creating a venturi effect. Theoretically, this should actually increase the amount of air flow through the chaffer. However, once I got going with yet another rain delay my sample was free of the excessive fines, but I was getting a large number of small leaves and stalk pieces. I always run my fan to max rpm(1150rpm while harvesting).
So, my theory for the air flow dynamic is thus:
While running the machine empty a venturi effect(low pressure) does occur, but when you add grain and trash to the top of the shoe and chaffer the restriction in air flow creates positive air pressure in the chamber under the shoe where the clean grain falls. The positive air pressure looks for an escape and it goes out the screen under the clean grain auger. Its kind of difficult to test my theory unless someone wants to volunteer to hang underneath my machine while I drive.
Does anyone have any knowledge of this situation? Does anyone make a kit to speed up the fan? I'd like to have a way to remove fines so that I can push air through my bins, but I don't want to add leaves and sticks.
So, my theory for the air flow dynamic is thus:
While running the machine empty a venturi effect(low pressure) does occur, but when you add grain and trash to the top of the shoe and chaffer the restriction in air flow creates positive air pressure in the chamber under the shoe where the clean grain falls. The positive air pressure looks for an escape and it goes out the screen under the clean grain auger. Its kind of difficult to test my theory unless someone wants to volunteer to hang underneath my machine while I drive.
Does anyone have any knowledge of this situation? Does anyone make a kit to speed up the fan? I'd like to have a way to remove fines so that I can push air through my bins, but I don't want to add leaves and sticks.