Originally Posted by Dave Jackson
Graviman, should wish to present a position, please do. However, attack the subject and not the person.
Dave, you are reading way too much into my last post.
After the PPRuNe discusion on pressure from ground effect, i went away and relearned stuff that at uni i thought i had understood. The fact that you are mentioning "pressure", but not qualifying it as "total pressure", "static pressure" or "dynamic pressure" means the discussion gets completely stuck on fundamentals. Total P = Static P + Dynamic P , and must be
constant along one streamline, but can be
different between two streamlines .That is why pitot-static ports are best placed on a probe in the same streamline for experimental work. When considering a streamline through a disk the
assumption is that the same streamline passes through the disk with an increase in total pressure (which can be induced dynamically or statically). What actually happens is that the assumption that the same streamline flows normally through the disk plane is just a mathematical convenience. From the moving aerofoil reference frame, the actual streamlines are helixing into the disk then helixing out at a steeper angle. Downstream the flow contracts or expands which determines whether the assumed total pressure increase is actually static or dynamic.
This was all stated concisely in my last post. How you came to feel that this was a personal attack is quite beyond me!
This is getting away from X2.
----
Interesting walkaround the LTH mockup, IFMU.,