If one has a specified allowed X length and Y height, into which a fillet can be placed to reduce stress concentrations, is there an equation which can be used to determine the optimal shape of the fillet?
I have looked into Baud Fillets and Thum-Bautz fillets, but I find that although these fillets work fantastically for a desired y height OR a desired x height, these don't work well when one has constraints on both of these dimensions. Furthermore, it seems scaling the fillet shape along the axis does not work well, in many cases ending up worse than a circular fillet.
If it is relevant, this is for fillets that are to be placed on the ID or OD of steps in tubing.
I know one option is various shape optimization algorithms, but I was hoping that there was some kind of out of the box solution that I could use to hopefully avoid this.