CFD modeling of phase change and coke formation in petroleum refining heaters

A three dimensional computational fluid dynamics (CFD) model is developed to predict the phase change and reactions inside the tubes of fired furnace. The model is constructed within the Eulerian framework in which the liquid phase is treated as a continuous phase while gas and solid phases are both considered as dispersed phases, and all phases are treated as interpenetrating continuum having separate transport equations. The thermal cracking kinetic model is validated against experimental data. Calculations are performed using the commercial packages ANSYS CFX 14.0. The temperature distribution, flow field, liquid-gas phase separation, and coke formation are predicted for different severities of petroleum type and tube wall temperature. The information predicted by the CFD model can be utilized in the optimal design of industrial fired furnaces.