Volume 9 (2013)

In this paper, a lightweight physical model and a fast numerical solver are proposed for the rendering of fluid catalytic cracking (FCC) dynamics in the riser cylinder reactor part of the FCC unit. For Real Time requirements, a trade-off between the model fidelity and numerical complexity is needed. The choice of the physical model and the way to solve it numerically is here completely driven by the Real Time virtual reality requirements on a standard Personal Computer. It has been possible to design a real time numerical model able to show the three-phase flow dynamics depending on design parameters (number of oil injection inlets, injection angles, flow rates, temperature of cracking). The obtained flow is qualitatively in agreement with what is expected in such kind of reactive flows: expansion zones, recirculating zones for catalyst, turbulence, privileged paths for the gas phase, etc. Of course, the rendering is purely qualitative, but accurate enough to reproduce the emerging behaviors of the flow and roughly understand what happens in a riser reactor. This is of course important from the Engineering point of view. A Graphic User Interface (GUI) allows for near-Real Time (RT) user interaction on environmental parameters with instantaneous response of the flow. A VTK-based visualization module allows us to visualize the three-dimensional fields of the three phases, simultaneously or independently. The software was built with open source technologies including Python, VTK, SWIG for C++ wrapping and wxPython and is portable over different operating systems like MS Windows and Linux. We think that this work is a new milestone toward a whole FCC unit closed- loop control simulator in the context of training and engineering. The perspective to use Teraflop-enabled Double Precision multicore GPU (see [9]) co-processors in the next months should allow us to use much more computational cells and particles, maybe up to a speedup factor of about 100 for a convincing realistic rendering. Moreover, the ability with such hardware to create software binding between data arrays and rendering objects with a high rate of frames per second is an attractive feature for real time visualization, simulation and interaction.

Keywords: Fluid catalytic cracking, riser, lightweight model, virtual reality, real time, numerical modeling, multiphase flow, particle method, three-dimensional visualization, VTK, GUI, interaction

Paper presented by: Professor Fayssal Benkhaldoun