The equivalent skin friction coefficient accounts for both separation drag and skin friction drag and is a fairly consistent value for aircraft types of the same class.
32.
The Kutta condition is an alternative method of incorporating some aspects of viscous effects, while neglecting others, such as skin friction and some other boundary layer effects.
33.
"' Skin friction drag "'is a component of profile drag that occurs differently depending on the type of flow over the lifting body ( laminar or turbulent ).
34.
In contrast, the air passing through the slot has not experienced this high local airspeed or high skin friction, and its total pressure remains close to the free-stream value.
35.
For a well designed aircraft, zero-lift drag ( or parasite drag ) is mostly made up of skin friction drag plus a small percentage of pressure drag caused by flow separation.
36.
A consequence of the turbulent boundary layer is increased skin friction relative to a laminar boundary layer, but this is very small compared to the increase in drag associated with separation.
37.
Where C _ { fe } is the equivalent skin friction coefficient, S _ { wet } is the wetted area and S _ { ref } is the wing reference area.
38.
Experimental data for gas streams agree approximately with above equation if the Prandtl numbers are near 1.0 and only skin friction is present in flow past a flat plate or inside a pipe.
39.
The head-down body position has to be carefully managed to be as streamlined as possible, while special helmets and slick body suits reduce skin friction, which is a function of surface area and texture.
40.
For those animals which undulate at intermediate Reynolds number ( Re ~ 10 1 ), such as the Ascidian larvae, both skin friction and form force account for the production of drag and thrust.
