This leads to higher lift pointing forward compared to the center of the wing.
![airfoil design youtube airfoil design youtube](https://i.ytimg.com/vi/73pJfoe4jUg/hqdefault.jpg)
The problem with negative yaw momentum is introduced when the airplane rolls which leads to higher aoa at the side which moves downwards. And at the wing tip some airfoils can help to reduce the negative yaw momentum (at least this is what I experienced with 3 prototypes.) As this airfoil is acting at low aoa you might want to optimize towards low drag at low cl and high drag at higher cl's. So it makes sense to use also different airfoils at each section. These kind of wings have different aoa at every section. One use case I have in mind is a horten wing. Std Wings which have basically the same conditions for every sections (despite induced aoa at the wing tip) are something already optimized to a point where not much gain in performance can be expected. Also most of the time optimisation doesn't make sense as the differences between real airfoil and the airfoil used for the computer design differ too much. If you don't know what you are doing, better to use some airfoil available. In the end, an optimizer is just another tool that may be useful for certain purposes.
![airfoil design youtube airfoil design youtube](https://hackaday.com/wp-content/uploads/2021/07/2021-07-08-8.png)
It's garbage in, garbage out, and there are a lot of potential pitfalls that require experience to avoid.
![airfoil design youtube airfoil design youtube](https://i.ytimg.com/vi/moEYSB-pudI/maxresdefault.jpg)
Of course, that's not to say that anyone could just push a button and end up with something good. My airplane used a custom airfoil produced by an optimizer.īesides being able to tailor the design to specific operating conditions, another advantage is that I could fix the trailing edge thickness based on the wood that would be used to build it. I think you're joking: you pretend to make a tool with which any random user can make better airfoils than the Seligs and Epplers and NACAs and RGs and HQs and Hepperles have done ? An optimizer only optimizes what the user has input, it's not some magic that will always give good results. So the user selects a start configuration and the optimizer should find a better design.