Apologies, I have just noticed we missed this post… I can only think of http://www.xflr5.com/xflr5.htm and that is not really suitable for high Re applications. There is Drela’s http://web.mit.edu/drela/Public/web/xfoil/ as well, not sure about high Mach number performance.

András

]]>András ]]>

When the Decode-1 script will be available?

Thank you

Nick ]]>

new to me. Anyhow, I’m definitely delighted I found it and I’ll be bookmarking and checking back often! ]]>

I’ve read your paper ‘Self-designing’ Parametric Geometries’ and inspired from that a lot, meanwhile may I ask two questions about this paper and MDO.

1. Model accuracy

Both in the book (Aircraft Aerodynamic Design: Geometry and Optimization) and in this paper, you have encuraged that using some abstract design parameter directly drive geometry to perform high level design instead of the conventional scalar and geometry modeling approach. This is quite promising, however, since different CAD may have diiferent numerical algorithm to do the modeling process,(like some CAD have multi section loft while others just use other ways to build surfaces) how we could ensure that the model builded from different CADs are the same if our design parameter have close relationship with a certain Geometry Modeling solftware?

2. Manufacturing

When considering the sweep function and dihedral function or something else, they can of course be a function of any order as we want, but will the wing resulted from these functions easy to build, or will this optimization result makes practical sense?

it is widely known that actuatlly the elliptical wing has been in use at the world war II(e.g British ‘splitfire’), and I’ve always heard that the reason we still commonly use trapezoid wing is that it could reach a nearly ecllips lift distribution at relatively low cost.

Like the NASA common research model whose dihedral function is not a line anymore, nowdays more complex model are being studied.so do we need to consider the cost factor when doing geometric optimization in research? Will it be practical / meaningful / ok to use some high order function to build the wing?

since I’m new to this area(MDO), please do not mind if they’re naive or odd , I’m puzzled by these questions a lot and will really apprciate that if some hints can be given on these.

]]>Since the book does not present a detailed numerical approch to calculate leading edge points using the functions, I thought it may going to use numerical Integration at first.

But in this case, the whole wings’ dihedral angle is not a function if we place it in to a cartesian coordination(a X will mapping multipul Ys), if I’m goint use gradient I will certainly get an Infinit tangent error on the tip when the step of integration is small enough, so I went to take a look at the code to see if there are some good ways to get the leps, then I found that it may also need some fix. ]]>

Thanks in advance. ]]>