I'm studying musical instrument design as a hobby, and could not find the answer to a question regarding instruments with a square-cross sectional bore. After seeing a design for a Paetzold square bass recorder, I've searched several recorder forums, Reddit AskPhysics and StackExchange with no luck while trying to find out what properties of a rectangular-prismatic bore differ from a cylindrical bore.
Let's say that I have a hollow rectangular prism and I attach an oscillator to one side. Would the location or functionality of the nodes be affected by an irregularly-shaped bore? How would the frequencies of the overtones in relation to the fundamental change?