Quote:
Originally Posted by bwilson4web
I get the impression 'pressure thrust' pulls in more than just the boundary layer. However, I'm wondering if rain and snow might cause problems?
|
Hi Bob, thanks for the questions.
If more air than just the boundary layer is pulled in the total efficiency begins to drop off. Boundary layer thickness will vary with speed but I'm not sure if the % of that layer will change to a great degree. The intake velocity will likely always be above free-stream velocity, thanks to the pressure drop at the suction inlet. This pressure drop may cause ice to form at the inlet even in above-freezing ambient temperatures (more on ice below).
The big difference with this vs Laminar Flow Control is that LFC is hugely dependent on absolutely precise control of the boundary layer, any contaminants like bugs, dirt, ice, gaps between panels, etc. will destroy the benefit. That is why LFC has not been put into commercial service despite multiple successful flight test programs.
Rain shouldn't be a big problem, but ice could clog the whole works. Heated parts should fix that and the heaters could be controlled so they are off when not needed to minimize their power costs.
-Dave B