NovaStark
Mechanical
- Feb 11, 2013
- 255
Good day all,
I am trying to practice my modeling skills with C2 so I am trying an HP Steam Turbine inlet line made from A 335 P11 and design conditions of 2000 psig at 950F.
I modeled everything as per isometric (including the actual installed hanger data) up to a termination point where running the analysis shows SUS, EXP and Alt-SUS cases to be acceptable.
However I did try to model the steam turbine for thermal growth which is made from cast chrome moly and done as a rigid element from one leg (anchored to the ground) to the inlet nozzle (placed an anchor here with Cnode). Now I may have gone wrong here as it appears from the drawing that the other turbine support under the exhaust is also an anchor so I wasn't sure if I'd need to model a rigid element from here back to the inlet nozzle.
My issue arrives when I look at the restraint report where I have quite high nozzle forces and moments. According my documentation the value of 3F+M < 8000 where F and M are resultant moments respectively (M alone is high in OPE, SUS and EXP cases). So I am sure that I went wrong somewhere as this line has been in service for over 10 years with no problems. Would someone be able to look at my model and guide as to where I have gone wrong ?
I am trying to practice my modeling skills with C2 so I am trying an HP Steam Turbine inlet line made from A 335 P11 and design conditions of 2000 psig at 950F.
I modeled everything as per isometric (including the actual installed hanger data) up to a termination point where running the analysis shows SUS, EXP and Alt-SUS cases to be acceptable.
However I did try to model the steam turbine for thermal growth which is made from cast chrome moly and done as a rigid element from one leg (anchored to the ground) to the inlet nozzle (placed an anchor here with Cnode). Now I may have gone wrong here as it appears from the drawing that the other turbine support under the exhaust is also an anchor so I wasn't sure if I'd need to model a rigid element from here back to the inlet nozzle.
My issue arrives when I look at the restraint report where I have quite high nozzle forces and moments. According my documentation the value of 3F+M < 8000 where F and M are resultant moments respectively (M alone is high in OPE, SUS and EXP cases). So I am sure that I went wrong somewhere as this line has been in service for over 10 years with no problems. Would someone be able to look at my model and guide as to where I have gone wrong ?
