An Rocky, Lee Jessica Audrey
Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850, USA.
Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14850, USA.
Life (Basel). 2022 Apr 29;12(5):660. doi: 10.3390/life12050660.
We present CAMDLES (CFD-DEM Artificial Microgravity Developments for Living Ecosystem Simulation), an extension of CFDEMCoupling to model biological flows, growth, and mass transfer in artificial microgravity devices. For microbes that accompany humans into space, microgravity-induced alterations in the fluid environment are likely to be a major factor in the microbial experience of spaceflight. Computational modeling is needed to investigate how well ground-based microgravity simulation methods replicate that experience. CAMDLES incorporates agent-based modeling to study inter-species metabolite transport within microbial communities in rotating wall vessel bioreactors (RWVs). Preexisting CFD modeling of RWVs has not yet incorporated growth; CAMDLES employs the simultaneous modeling of biological, chemical, and mechanical processes in a micro-scale rotating reference frame environment. Simulation mass transfer calculations were correlated with Monod dynamic parameters to predict relative growth rates between artificial microgravity, spaceflight microgravity, and 1 g conditions. By simulating a microbial model community of metabolically cooperative strains of and we found that the greatest difference between microgravity and an RWV or 1 g gravity was when species colocalized in dense aggregates. We also investigated the influence of other features of the system on growth, such as spatial distribution, product yields, and diffusivity. Our simulation provides a basis for future laboratory experiments using this community for investigation in artificial microgravity and spaceflight microgravity. More broadly, our development of these models creates a framework for novel hypothesis generation and design of biological experiments with RWVs, coupling the effects of RWV size, rotation rate, and mass transport directly to bacterial growth in microbial communities.
我们展示了CAMDLES（用于生命生态系统模拟的计算流体力学-离散单元法人工微重力开发），它是CFDEM耦合的扩展，用于模拟人工微重力装置中的生物流动、生长和传质。对于伴随人类进入太空的微生物而言，微重力引起的流体环境变化可能是其太空飞行经历中的一个主要因素。需要通过计算建模来研究地面微重力模拟方法在复制这种经历方面的效果如何。CAMDLES纳入了基于主体的建模，以研究旋转壁式生物反应器（RWV）中微生物群落内物种间的代谢物运输。先前对RWV的计算流体力学建模尚未纳入生长过程；CAMDLES在微观尺度的旋转参考系环境中对生物、化学和机械过程进行同步建模。模拟传质计算与莫诺德动力学参数相关联，以预测人工微重力、太空飞行微重力和正常重力条件下的相对生长速率。通过模拟 和 的代谢合作菌株的微生物模型群落，我们发现微重力与RWV或正常重力之间的最大差异在于物种在密集聚集体中共定位时。我们还研究了系统的其他特征对生长的影响，如空间分布、产物产量和扩散率。我们的模拟为未来使用该群落进行人工微重力和太空飞行微重力研究的实验室实验提供了基础。更广泛地说，我们对这些模型的开发创建了一个用于生成新假设和设计RWV生物实验的框架，将RWV大小、转速和传质的影响直接与微生物群落中的细菌生长联系起来。
