Wayne Parham Messages: 18789 Registered: January 2001
Illuminati (33rd Degree)
You can model the horn in Hornresp with abrupt transitions to see what you can expect. You can also radius the interface between conical and tractrix sections and measure the results and compare. The final shape may be something like a quadratic throat with mouth exit radiused like a tractrix, so you may want to do some research on the quadratic throat design. There's an introduction at the link.