Perpustakaan Digital ITB

Kettle reboilers are widely used to supply thermal energy for distillation and gas-sweetening processes, but complex shell-side multiphase hydrodynamics can induce dynamic forces on the tube bundle, potentially leading to flow-induced vibration (FIV) and tube failure. HTRI, the conventional industry tool, evaluates FIV using a crossflow velocity from one-dimensional empirical correlations discretized into only a few bundle zones, which may not capture localized velocity peaks from non-uniform two-phase flow. This study compares the shell-side crossflow velocity, fluidelastic instability (FEI), and vortex shedding susceptibility of a kettle reboiler tube bundle in amine regeneration service, as predicted by HTRI and Computational Fluid Dynamics (CFD) using a two-dimensional Volume of Fluid model coupled with the Lee phase-change model. The HTRI duty deviated by only 0.02%, and the CFD heat flux deviated by 15.2%, from independent verification. The CFD-resolved crossflow velocity (1.38 m/s) was 59.96% lower than HTRI's (3.45 m/s). Both methods predicted stability against FEI, though HTRI gave a narrower margin (26.19% vs. 54.39%). For vortex shedding, the two methods diverged in outcome: HTRI's amplitude exceeded the allowable limit by 14.67%, while CFD's remained well within it. Given the greater risk of underestimating vibration, HTRI's results were adopted as the governing, conservative basis for design conclusions.