optimization of wave drag function ( double summation term)



On 2013-10-08, ccitak <ccitak at metu.edu.tr> wrote:

> Im stucked with the function added to this email (wave drag function) I 
> want to optimize wave drag function ' F ' ( objective function)
> S is the cross sectional area
> S'' is the 2nd derivative of S
> n is the number of cross sections taken from aircraft
>
> My questions are what type of optimization method can we use ? how can 
> we perturb the x-sectional areas ? Since we have approximately
> 100 x-sections, how can we calculate the gradient ( if method is 
> gradient-based, ..) ?

My advice is to replace the summations by integrals. I believe it then
becomes a variational problem. Maybe you will have to assume a specific
form for S in order to make progress; I don't know. By the way, with
respect to what variable are the derivatives taken?

Sorry I can't be more helpful,

Robert Dodier