On the fast modeling of species transport in fluidized beds using recurrence computational fluid dynamics

Abstract

Due to variety of scale dynamics evolved in gas–solid flows, most of its numerical description is limited to expensive short durations. This has made the slow processes therein, such as the chemical species conversion, to be out of an appropriate reach. In this work, an application of the transport‐based recurrence computational fluid dynamics (CFD) has been introduced for the fast modeling of passive scalar transport, which is considered as species conversion and heat transfer in fluidized beds. The methodology discloses the recurrent dynamics during a short‐term full CFD simulation as Lagrangian shift operations upon which a passive scalar can infinitely be traced. Apart from convecting, a proper approach based on the turbulent kinetic energy of tracked dynamics is introduced for modeling the physical diffusion of the scalar transported. Our outcomes have revealed a subtle chasing to the full CFD species simulation with a speed‐up up to 1,600.

A fast modeling of chemical reactions in industrial‐scale olefin polymerization fluidized beds using recurrence CFD

“…Similarly to our recent work in Dabbagh et al, 33 the short‐term non‐reactive simulation (here using the cgTFM), is employed to investigate, a priori the recurrence properties of the system. Namely, the recurrence time step Δ t rec is decided basing on the pseudo‐periodicity of the system (bubbles evolution) at which the flow can almost be repeated.…”

“…Namely, the recurrence time step Δ t rec is decided basing on the pseudo‐periodicity of the system (bubbles evolution) at which the flow can almost be repeated. Following the time histories of active fields such as, and , taken inside the bed at the probe { T 0 } (see Figure 1a), and shown in Figure 2a, the proper determination of Δ t rec reads 0.03 s (≡ 60Δ t ), with, 33 …”

“…This novel methodology has shown a feasible capability to simulate long‐duration processes such as chemical species conversion and heat transfer, for single 30,32 and multiphase flows, 29,33 in a fast and cheap way. For the case of a gas–solid fluidized bed, lab‐scale reactors were successfully investigated in a fast stable and transient heating process 33,34 . Recently, the authors proposed an enhanced version of transport‐based rCFD 33 and employed it for the fast prediction of species and heat propagation on both gas and solid phase.…”

Steel Alloy Homogenization During Rheinsahl–Heraeus Vacuum Treatment: Conventional Computational Fluid Dynamics, Recurrence Computational Fluid Dynamics, and Plant Observations

“…[ 15 ] Further details with regard to the modeling of physical diffusion are given in the literature. [ 18,19 ] At this place, we therefore just present the main modeling features and abstain from a detailed description of the rCFD methodology.…”

“…Although rCFD is still in development, different versions of rCFD have already been applied successfully to turbulent single‐phase flow, [ 15–18 ] bubble columns, [ 12 ] and fluidized beds. [ 14,19,20,21 ]…”