Anyone have pointers to modeling drag of leading edge slats when in their closed position? I think this breaks down to three parts:
1) Trip from laminar to turbulent flow. Seems inevitable, even with the favorable pressure gradient this far forward.
2) Gap leakage. Approximately zero for a well-sealed design, ignoring.
3) Drag of the surface discontinuities/“gaps”, which are significantly bigger than normal discontinuities (rivet beads, butt joints) but still on the same order of magnitude as the boundary layer. This is what I’m struggling with documentation for.
I have my own preferences on clean leading edge vs slat, but I’d at least like to understand how to run the trade of slats vs larger wing for drag minimization with wing sized for fixed stall speed.
1) Trip from laminar to turbulent flow. Seems inevitable, even with the favorable pressure gradient this far forward.
2) Gap leakage. Approximately zero for a well-sealed design, ignoring.
3) Drag of the surface discontinuities/“gaps”, which are significantly bigger than normal discontinuities (rivet beads, butt joints) but still on the same order of magnitude as the boundary layer. This is what I’m struggling with documentation for.
I have my own preferences on clean leading edge vs slat, but I’d at least like to understand how to run the trade of slats vs larger wing for drag minimization with wing sized for fixed stall speed.