Determination method of pore parameters in porous media for evaporation process based on pore network model and fractal theory

The evaporation cooling process in porous media is significantly influenced by its pore properties, which are essential for understanding thermal transfer behaviors. This study presents a novel approach for determining the pore parameters of porous media, focusing on their influence on the evaporation process. By integrating the pore network model (PNM) with fractal theory, key parameters such as porosity, pore and tortuosity fractal dimension are extracted and a mathematical relationship between these pore parameters and macroscopic evaporative processes is established. Additionally, a 3D irregular surface model, constructed using the Weierstrass-Mandelbrot (W-M) function, is employed to characterize the fractal dimension and height scaling parameter of the pore structure. This study thoroughly investigates in detail the influence of pore fractal dimension and porosity on evaporation process and the evolution of evaporative interface by simulation code. The results demonstrate that the effects of the pore fractal dimension and porosity on parameters of evaporation process are opposite, but both show a decreasing trend in the average height of evaporative interface (RMS value) and an increasing trend in the irregularity (STD value). This work offers valuable insights for the design and optimization of porous materials in applications such as thermal management systems, and stable evaporation technologies, providing a deeper understanding of heat and mass transfer in complex porous media.