Let's say we have a pipe with water flowing through it and obstacle is inserted into the pipe and is rigidly fixed to the inner wall so that it does not get washed away.
What forces are exerted by the fluid on the object? The only one I can think of is drag (which is this). I was also thinking that the restriction in the pipe caused by the obstacle would induce a pressure drop across that obstacle which would also generate a force on top of the drag force. Is this true?
What other fluid forces would this obstacle experience?