Dear All,
I am starting my first slug analysis, on an 8" and 4" blow downline (2-phase flow,liquid + gas), which has displaced (jumped) on site.
I have been through the CAESAR II manual, COADE Newsletters and this forum and they were very help full, giving me a jump start to dynamic analysis.
There was a post with the topic "slug analysis", which recommends a spectrum analysis for slug flow problems due to the many unknowns in slug flow. Thereto I am adopting the spectrum analysis method for the slug analysis (conservative).
I have obtained data regarding the flow from the process department and was able to calculate the forces acting at the elbows of the system, along with assigning the associated directions.
I realize that for each elbow, there will be a separate load case, as we are assuming a single one time occurance of the impulse.
The next step of how to generate the spectrum, is unclear to me. I can use an assumed slug length and the liquid velocity in the stream to calculate the time taken to round the bend, and that this force will be applied in a trapezoidal form. An example of generating the spectrum is given in the application guide but how can it be applied to slug flow case.
In summary my doubts:
1. How to estimate slug length
2. How to generate the DLF/Spectrum for slug flow to take care of the total system response.
I would gratefull for any help.
Regards
_________________________
Junior Piping Engineer