MODELING MOISTURE TRANSPORT IN POROUS DIELECTRIC STRUCTURES FOR ADVANCED HUMIDITY SENSING IN INTELLIGENT AND ASSISTIVE SYSTEMS

Abstract

To design high-performance humidity sensors for next-generation intelligent systems, assistive technologies, and autonomous robotic platforms, a comprehensive understanding of moisture transport processes in porous dielectric materials is essential. Moisture sensing plays a critical role in environmental monitoring, healthcare applications, smart infrastructure, and robotic systems operating in dynamic environments. In porous structures containing nanoscale and micro-scale pores, water vapor transport is governed by both molecular diffusion and Knudsen diffusion, making conventional diffusion models inadequate when pore dimensions approach the molecular mean free path. This work employs the Bosanquet approximation to capture the combined effects of molecular and Knudsen diffusion and performs a numerical investigation of moisture transport in porous dielectric structures. Parametric simulations are conducted for pore radii ranging from 50 nm to 1000 nm under standard operating conditions. The influence of pore size on Knudsen diffusion, effective diffusion coefficients, and transport resistance is systematically analyzed. Results reveal a transition diffusion regime in which both molecule–molecule and molecule–wall interactions significantly affect transport behavior. The findings demonstrate that pore geometry strongly influences moisture transport characteristics and provide valuable design insights for the development of advanced humidity sensors and sensing systems supporting assistive technologies, smart environments, robotic perception, and future autonomous monitoring applications.