A one-dimensional Finite Difference Model for Breathing Wall components under time dependent Dirichlet boundary conditions is presented. The algorithm undergoes a comprehensive validation against a dynamic analytical model, under either sinusoidal and generically periodic boundary conditions, adopting different airflow velocities and in relation to capacitive and resistive materials alternatively. It is found that the accurate prediction of the temperature profile inside the wall is influenced primarily by the timestep, whose optimal value can be identified through a preliminary frequency analysis of the boundary conditions. Moreover, for a better prediction of the surface heat flow density, and especially in insulating materials, refining the space grid below 1 mm is recommended, as well as the adoption of a 3-point numerical scheme. The numerical model is finally tested against experimental data on a porous concrete wall, showing that numerical errors may compare to other sources of uncertainties, regarding materials properties and boundary conditions.

提出了一种与时间相关的狄利克雷边界条件下的呼吸墙构件一维有限差分模型。该算法在正弦曲线和一般周期性边界条件下，针对动态分析模型进行了全面验证，采用了不同的气流速度以及相对于电容性和电阻性材料。发现壁内温度分布的准确预测主要受时间步的影响，其最佳值可以通过边界条件的初步频率分析来确定。此外，为了更好地预测表面热流密度，尤其是在绝热材料中，建议将空间网格细化到1 mm以下，并建议采用三点数值方案。