Modeling of the Reboiler (with an Expansion joint in shell) in Caesar II:
Initially model the reboiler as a rigid body following below mentioned steps. Refer attached drawing (Fig. 1) as reference:
1. Model node 10-20 and 20-30 with tube outlet temperature and pressure considering channel material, diameter, thickness, length and fluid density (Also include insulation thickness and density if any) from Rebolier General Arrangement (Henceforth called GA) drawing.
2. Model node 30-40, 40-50 and 60-70 with shell average temperature and shell design pressure considering shell material and dimensions as mentioned in reboiler GA.
3. Model element 30-70 with channelside average temperature and design pressure taking tube material, shell diameter and thickness from GA drawing.
4. Model 70-80 and 80-90 with tube inlet temperature and pressure considering channel material, diameter, thickness and length.
Fig. 1: Typical Reboiler diagram for modeling in Caesar II
5. Model element 50-100 with shellside properties and model the support restraint at node 100. Similarly model all other support elements as required from GA drawing (check 2 lug, 3 lug or 4 lug supported system)
6. Now make the elements 10-20, 20-30, 70-80 as flexible (i.e, non rigid).
7. Check the total operating weight of the reboiler from GA (if operating weight is not available assume 70% of water filled weight) and the weight already considered in elements mentioned in step no 6 (considering fluid and insulation; you can do it easily by clicking single run button in caesar II). Provide the remaining balance weight in rigid element 30-70 (tube weight). Recheck once again by clicking single run button to ensure the actual weight in caesar model matches with weight provided in GA.
In case there is no expansion joint in shell, model element 30-70 with shellside average temperature. Rest all other parameters will remain the same.
As you are planning for a reboiler piping I am sure you know the modelling of column and attached piping. So i am not describing it. So model the column and attached piping to make a complete system as shown in attached figure (Fig. 1).