Fabian Kleischmann, Bernhard Vowinckel, Eckart Meiburg, Paolo Luzzatto-Fegiz
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引用次数: 0
Abstract
Microgravity experiments on board the International Space Station, combined with particle-resolved direct numerical simulations, were conducted to investigate the long-term flocculation behavior of clay suspensions in saline water in the absence of gravity. After an initial homogenization of the suspensions, different clay compositions were continuously monitored for 99 days, allowing a detailed analysis of aggregate growth through image processing. The results indicate that the onboard oscillations (g-jitter) may have accelerated the aggregation process. Aggregate growth driven by these oscillations is found to occur at a faster rate than aggregation caused by Brownian motion. Complementary numerical simulations confirm this hypothesis and also demonstrate that parameters such as the oscillation amplitude and the solid volume fraction influence growth acceleration. These findings highlight that oscillations may act as a previously unrecognized mechanism that contributes to particle aggregation in fluids.
npj MicrogravityPhysics and Astronomy-Physics and Astronomy (miscellaneous)
CiteScore
7.30
自引率
7.80%
发文量
50
审稿时长
9 weeks
期刊介绍:
A new open access, online-only, multidisciplinary research journal, npj Microgravity is dedicated to publishing the most important scientific advances in the life sciences, physical sciences, and engineering fields that are facilitated by spaceflight and analogue platforms.