Chau Jessica Furrer, Or Dani, Sukop Michael C
Department of Civil and Environmental Engineering, University of Connecticut, Storrs, Connecticut, USA.
Water Resour Res. 2005 Aug;41(8):W08410. doi: 10.1029/2004wr003821.
Liquid distributions in unsaturated porous media under different gravitational accelerations and corresponding macroscopic gaseous diffusion coefficients were investigated to enhance understanding of plant growth conditions in microgravity. We used a single-component, multiphase lattice Boltzmann code to simulate liquid configurations in two-dimensional porous media at varying water contents for different gravity conditions and measured gas diffusion through the media using a multicomponent lattice Boltzmann code. The relative diffusion coefficients (D rel) for simulations with and without gravity as functions of air-filled porosity were in good agreement with measured data and established models. We found significant differences in liquid configuration in porous media, leading to reductions in D rel of up to 25% under zero gravity. The study highlights potential applications of the lattice Boltzmann method for rapid and cost-effective evaluation of alternative plant growth media designs under variable gravity.
为了更好地理解微重力环境下的植物生长条件，研究了不同重力加速度下非饱和多孔介质中的液体分布以及相应的宏观气体扩散系数。我们使用单组分多相格子玻尔兹曼代码来模拟不同重力条件下二维多孔介质中不同含水量时的液体形态，并使用多组分格子玻尔兹曼代码测量气体在介质中的扩散。有重力和无重力模拟的相对扩散系数（D rel）作为充气孔隙率的函数，与实测数据和已建立的模型吻合良好。我们发现多孔介质中液体形态存在显著差异，导致在零重力下D rel降低高达25%。该研究突出了格子玻尔兹曼方法在可变重力条件下快速且经济高效地评估替代植物生长介质设计方面的潜在应用。
