Hi Maury,
Not sure why you're getting that output. An arc will normally produce smooth corners not facetted ones (except for where it joins onto the straight edges) You'll normally only get all the vertical edges showing if you have exploded the curve before extruding the face.
Anyhow, to solve the problem, just paint over all the vertical lines with Eraser whilst holding Ctrl down. Done!

[Command on Mac OS]

Sorry, I was not paying attention on your OS (although this is one of the reasons we require these fields 😒 )

Anyway, you got it right now.

Are these 3d geometry formats? Or do they pertain more to the fluid and how it moves? You're making it easy to give a good answer as to whether someone can help you 😄