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Why do swept wings stall at the tip?
Swept and tapered wings will tend to stall at the tips first because of the high wing loading at the tips. The boundary layer outflow also resulting from wing sweep slows the airflow and reduces the lift near the tips and further worsens the situation.
Is higher lift coefficient better?
Section lift coefficient depends on angle of attack. A greater angle of attack means higher lift coefficient. The additional airflow going over the wing the farther out you get increases local angle of attack and therefore the local section lift coefficient.
How does downwash affect the lift coefficient of a wing?
For three dimensional wings, the downwash generated near the wing tips reduces the overall lift coefficient of the wing. The lift coefficient also contains the effects of air viscosity and compressibility.
What is the distribution of local lift coefficient?
We now turn our attention to the distribution of local lift coefficient over the wing. The local lift coefficient is the local lift per running distance divided by the local wing chord and the dynamic pressure of the airflow. C = local wing chord.
How is the distribution of lift coefficient on a constant chord wing?
On a constant-chord wing the distribution of lift coefficient has the same shape as the distribution of gross lift. The lift at each station along the wing is normalized by the same constant chord and dynamic pressure to get a lift coefficient, so the distribution scales by a constant factor when going from lift to lift coefficient.
When to use the lift coefficient and viscosity?
To correctly use the lift coefficient, we must be sure that the viscosity and compressibility effects are the same between our measured case and the predicted case. Otherwise, the prediction will be inaccurate. For very low speeds (< 200 mph) the compressibility effects are negligible.