Unraveling dispersion and buoyancy dynamics around radial A + B → C reaction fronts: microgravity experiments and numerical simulations

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Yorgos Stergiou - , Helmholtz-Zentrum Dresden-Rossendorf, TUD Dresden University of Technology (Author)
  • Darío M. Escala - , Université libre de Bruxelles (ULB) (Author)
  • Paszkál Papp - , University of Szeged (Author)
  • Dezső Horváth - , University of Szeged (Author)
  • Marcus J.B. Hauser - , Otto von Guericke University Magdeburg (Author)
  • Fabian Brau - , Université libre de Bruxelles (ULB) (Author)
  • Anne De Wit - , Université libre de Bruxelles (ULB) (Author)
  • Ágota Tóth - , University of Szeged (Author)
  • Kerstin Eckert - , Chair of Transport Processes at Interfaces, Helmholtz-Zentrum Dresden-Rossendorf (Author)
  • Karin Schwarzenberger - , Chair of Transport Processes at Interfaces, Helmholtz-Zentrum Dresden-Rossendorf (Author)

Abstract

Radial Reaction–Diffusion–Advection (RDA) fronts for A + B → C reactions find wide applications in many natural and technological processes. In liquid solutions, their dynamics can be perturbed by buoyancy-driven convection due to concentration gradients across the front. In this context, we conducted microgravity experiments aboard a sounding rocket, in order to disentangle dispersion and buoyancy effects in such fronts. We studied experimentally the dynamics due to the radial injection of A in B at a constant flow rate, in absence of gravity. We compared the obtained results with numerical simulations using either radial one– (1D) or two–dimensional (2D) models. We showed that gravitational acceleration significantly distorts the RDA dynamics on ground, even if the vertical dimension of the reactor and density gradients are small. We further quantified the importance of such buoyant phenomena. Finally, we showed that 1D numerical models with radial symmetry fail to predict the dynamics of RDA fronts in thicker geometries, while 2D radial models are necessary to accurately describe RDA dynamics where Taylor–Aris dispersion is significant.

Details

Original languageEnglish
Article number53
Number of pages9
Journalnpj Microgravity
Volume10 (2024)
Issue number1
Publication statusPublished - 9 May 2024
Peer-reviewedYes