hello everyone,

The Sytem consist of straight pipeline (along X axis) of 6" pipe and 12.7mm thck, T1=35°c and P1=29.4bar, Insulation thck 40mm and density of 3031kg/cu.m, ambient 15°c

while considering wave in caesar for subsea pipeline analysis using DNV code, the caesar shows diferent results (displacement, sresses, bending moment)in +WAVE1(Direction cosines x=0, z=1) and -WAVE1.
Have enabled Von-mises.
X= pipe axis, Z=lateral, Y=vertical
Tried to varify the results when the load case modified to +WAVE1(Direction cosines x=0, z=1) and +WAVE2 (Direction cosines x=0, z=-1), still the results are varying.
have attached the load case and the WAVE Card.


kindly suggest why the results are varying when the same parameters are used (other than WAVE direction) and the system is symetric in shape.
Using CAESAR II 2014 7.00.03.0100 (BUILD 150704)

Regards
jossy

The transverse force (lift) will vary in direction based on the fluid velocity vector. As an example, consider a vertical riser with wave and/or current vectors in (1, 0, 0). The transverse force will be opposite in direction compared to the same wave and/or current applied in (-1, 0, 0).

richard,

in case of vertical riser there is change in water depth which can result in differnt force acting on the riser. and as u said about the transvrse wave, the velocity will be varying as the dept varies.

I wanted to know why the caesar shows diffrent result when we change the load case as +WAVE1 and -WAVE1, when the pipe is horizontal fully restrained line (symmetric along the half). Assuming that the wave velocity remains same at same elevation. (refer #65177)

Because in one case the transverse force will be up and when the velocity is reversed it will be down.