Benkhaled Maroua, Ouldboukhitine Salah-Eddine, Bakkour Amer, Amziane Sofiane
Institut Pascal, Université Clermont Auvergne, CNRS, SIGMA Clermont, F-63000 Clermont-Ferrand, France.
Department of Physics, Faculty of Sciences, Lebanese University, Hadath, Beirut, Lebanon.
Materials (Basel). 2021 Nov 16;14(22):6903. doi: 10.3390/ma14226903.
Plant-based concrete is a construction material which, in addition to having a very low environmental impact, exhibits excellent hygrothermal comfort properties. It is a material which is, as yet, relatively unknown to engineers in the field. Therefore, an important step is to implement reliable mass-transfer simulation methods. This will make the material easy to model, and facilitate project design to deliver suitable climatic conditions. In recent decades, numerous studies have been carried out to develop models of the coupled transfers of heat, air and moisture in porous building envelopes. Most previous models are based on Luikov's theory, considering mass accumulation, air and total pressure gradient. This theory considers the porous medium to be homogeneous, and therefore allows for hygrothermal transfer equations on the basis of the fundamental principles of thermodynamics. This study presents a methodology for solving the classical 1D (one-dimensional) HAM (heat, air, and moisture) hygrothermal transfer model with an implementation in MATLAB. The resolution uses a discretization of the problem according to the finite-element method. The detailed solution has been tested on a plant-based concrete. The energy and mass balances are expressed using measurable transfer quantities (temperature, water content, vapor pressure, etc.) and coefficients expressly related to the macroscopic properties of the plant-based concrete (thermal conductivity, specific heat, water vapor permeability, etc.), determined experimentally. To ensure this approach is effective, the methodology is validated on a test case. The results show that the methodology is robust in handling a rationalization of the model whose parameters are not ranked and not studied by their degree of importance.
植物基混凝土是一种建筑材料，除了对环境影响极低外，还具有出色的湿热舒适性能。这种材料在该领域的工程师中相对还不太为人所知。因此，重要的一步是实施可靠的传质模拟方法。这将使该材料易于建模，并有助于项目设计以提供适宜的气候条件。近几十年来，已经开展了大量研究来开发多孔建筑围护结构中热、空气和水分耦合传递的模型。以前的大多数模型基于鲁伊科夫理论，考虑了质量积累、空气和总压力梯度。该理论认为多孔介质是均匀的，因此可以基于热力学基本原理得出湿热传递方程。本研究提出了一种求解经典一维热、空气和水分（HAM）湿热传递模型的方法，并在MATLAB中实现。该求解方法根据有限元法对问题进行离散化。详细的求解方法已在植物基混凝土上进行了测试。能量和质量平衡用可测量的传递量（温度、含水量、蒸汽压等）以及与植物基混凝土宏观性质明确相关的系数（导热系数、比热容、水蒸气渗透率等）来表示，这些系数是通过实验确定的。为确保该方法有效，在一个测试案例上对该方法进行了验证。结果表明，该方法在处理一个参数未排序且未按重要程度研究的模型的合理化方面具有鲁棒性。
