Posted by: Michael_Fletcher
CAESAR II, Rectangular Ducting, EJs and Unexpected Results - 01/12/18 09:42 AM
Please reference the screenshots.
Some notes:
1) Ducting is significantly hotter than the "pipe."
2) Ducting has a higher coefficient of thermal expansion than the "pipe"
3) Ducting has supports under the vertical sections, with friction.
What I would expect to happen is that because the ducting is so much hotter than the pipe, and because it is partly restrained, that all 3 expansion joints in each horizontal run would be compressing. This is because a relatively unrestrained horizontal run would have neither tension or compression. If the ducting were cooler, then you'd expect tension.
So, while I get thermal expansion of the ducting (the angle of the duct moves away from centroid of expansion), the bellows are also expanding - regardless if I specify 0 pressure thrust.
The vertical expansion joints are the only ones that are compressing. Can anyone explain why the horizontal ones are expanding despite restraints on the ends and 0 thrust?
Some notes:
1) Ducting is significantly hotter than the "pipe."
2) Ducting has a higher coefficient of thermal expansion than the "pipe"
3) Ducting has supports under the vertical sections, with friction.
What I would expect to happen is that because the ducting is so much hotter than the pipe, and because it is partly restrained, that all 3 expansion joints in each horizontal run would be compressing. This is because a relatively unrestrained horizontal run would have neither tension or compression. If the ducting were cooler, then you'd expect tension.
So, while I get thermal expansion of the ducting (the angle of the duct moves away from centroid of expansion), the bellows are also expanding - regardless if I specify 0 pressure thrust.
The vertical expansion joints are the only ones that are compressing. Can anyone explain why the horizontal ones are expanding despite restraints on the ends and 0 thrust?