A novel passive method for regulating both air temperature and relative humidity of the microenvironment in museum display cases

Abstract

Display cases are widely utilized in museums to build an appropriate microenvironment for artifacts. In this study, a novel passive method is utilized to regulate both the temperature and relative humidity simultaneously of the microenvironment in museum display cases by proposing the concept of composite temperature and humidity control materials (CTHCM), which can be fabricated by combining both phase change material (PCM) and silica gel. The PCM is helpful to reduce the range of air temperature changes caused by melting or solidification processes, while the silica gel is helpful to reduce the range of relative humidity changes caused by adsorption or desorption processes. In this study, a coupled heat and mass transfer model is established to analyze the temperature-regulating and humidity-regulating performance of CTHCM using the software COMSOL Multiphysics. The influences of thermodynamic parameters of materials on temperature-regulating and humidity-regulating performance are also analyzed numerically. Results show that CTHCM is able to regulate the air temperature and relative humidity of the microenvironment in museum display cases effectively. It performs well in temperature-regulating as the phase change latent heat increases, and performs well in humidity-regulating as the water vapor permeability or moisture diffusivity increases.