And this is the turning vane with the ramp. Sorry that I could not get the whole area in focus.

The idea was to locate the ramp walls at the center of each turning vane. Since the air is contained in a box until the turning vanes and with the airfoil splitter, I hope that this will provide some significant improvement in the air flow. It's still a tight turn and I am certain it will be turbulent, but I hope it is an improvement.

The thought is that since the ramp ends at the turning vanes, the air will be slowed by half when it arrives. The air then turns and heads forward and expands again another 2X, and so it should slow to an end velocity equal to 25% of airspeed. OK - I have no idea if that is the real fluid dynamics, but that's my thought process.

In subsequent work I will add some water dams to keep the out of the vents. I also plan to put some micro into the back of the plenum to help move the water into the drains. My measurements show that the plenum is headed downhill about 10 degrees. I will use some of that to raise the floor of the duct so that the drain fittings can be lower than the level of the floor. I hope this improves the drainage and, in the end, prevent gunk build up back there. I will also add fill the floor of the plenum to prevent water from being held in all of those little divots.

If this works, I have a solution in mind for Bob and Brett and anyone else who has their plenum in place and needs to improve the air flow.

2/16/2009   Picture 72