So for years on the mycology, plant tissue culture, and DIY laboratory websites there has been this ongoing debate on how to achieve laminar flow in a home built laminar flow hood.
It is generally accepted that a squirrel blower is effective at creating this laminar flow using the set up in the image posted above. Many people are interested in using inline centrifugal fans because they are cheaper than squirrel blowers, more quiet, more energy efficient, and potentially more compact. The build for a laminar flow hood using these inline fans look, generally, like the two samples at the bottom of this link (http://www.fungifun.org/English/Flowhood#construction).
The main question is whether these inline fans will produce laminar flow. The argument is that the air pushed by these fans is turbulent and so will exit the HEPA filter in a turbulent fashion. It seems to me that so long as the plenum is air tight besides the entry point(fan location) and exit point(HEPA filter), the plenum will achieve a static pressure (based upon the cfm of air driven by the fan and the resistance of the HEPA filter) and flow smoothly out of the HEPA.
Would this be totally wrong? If so, is there a way to build the DIY flow hood to achieve a laminar flow using one of these inline centrifugal fans?