- #1
ken
- 51
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Hi
I wanted to get clear on this conclusion of lift distribution along the span of a wing.
Graphs in texts show that for constant chord wings, Cl distribution along the span is eliptical.
Conclusions:
1.Induced incidence is greater towards the tip.
2.Lift force at the root is PI/4 greater than mean and as local chord is a constant, lift force falls away in the same eliptical relationship as Cl toward the tip.
Now take an eliptical wing plan form. Texts show that CL is constant almost to the tip. Conclusions, except right near the tip:
1. Induced incidence is constant across the span.
2. As local lift force is a product of Cl and local chord and Cl is constant, the lift force distribution follows the same eliptical relationship as the chord.
The two plan forms result in the same eliptical lift force distribution along the span. Now logic would seem to dictate what defies common sense and seems to be way too easy but could it be that wing taper does not effect the distribution of lift force along the span. Is this conclusion correct or are the texts incorrect?
I can so only these 2 possabilities.
Regards,
Ken
I wanted to get clear on this conclusion of lift distribution along the span of a wing.
Graphs in texts show that for constant chord wings, Cl distribution along the span is eliptical.
Conclusions:
1.Induced incidence is greater towards the tip.
2.Lift force at the root is PI/4 greater than mean and as local chord is a constant, lift force falls away in the same eliptical relationship as Cl toward the tip.
Now take an eliptical wing plan form. Texts show that CL is constant almost to the tip. Conclusions, except right near the tip:
1. Induced incidence is constant across the span.
2. As local lift force is a product of Cl and local chord and Cl is constant, the lift force distribution follows the same eliptical relationship as the chord.
The two plan forms result in the same eliptical lift force distribution along the span. Now logic would seem to dictate what defies common sense and seems to be way too easy but could it be that wing taper does not effect the distribution of lift force along the span. Is this conclusion correct or are the texts incorrect?
I can so only these 2 possabilities.
Regards,
Ken