Effects of gravity modulation on the dynamics of a radial A+B→C reaction front

• Radial A + B → C reaction fronts were investigated under modulated gravity for the first time • Reaction-Diffusion-Convection dynamics are significantly affected by gravity modulation even in Hele-Shaw calls with small gap height • Production rate is increased when fronts are subject to a modulated gravity environment • Production rate is decreased under pure microgravity conditions The dynamics of radial A + B → C reaction fronts can be affected by buoyancy-driven convection. Motivated by recent advances in reaction-diffusion-advection (RDA) systems theory, we investigated experimentally a radial A + B → C RDA system under modulated gravity, using a Hele-Shaw cell setup onboard a parabolic flight. We evaluated characteristic properties of the RDA models, such as the temporal evolution of the total amount of product C , the width and position of the reaction front and compared them with theoretical predictions. During increased gravity, we observed an increase in the total amount of product C , formed and the front width, compared to the corresponding normal-gravity experiments, caused by the stronger buoyancy-driven convection in the former case. Finally, we report on experiments performed entirely in absence of gravity, eliminating buoyancy-driven convection. Despite the short observation time, comparison with ground experiments showed the effect of buoyant convection on radial RDA fronts, enhancing mixing and increasing product generation.