The Analysis of Coupled Heat and Moisture Transfer in Building Envelop Based on Numerical Simulation

Abstract:

The research of coupled heat and moisture transfer is a complex process, which is the fundamental of decreasing building energy consumption; improving IAQ and increasing the durability of building envelop. CHAMPS-BES software is an outcome of a joint effort between Building Energy and Environmental Systems Laboratory (BEESL) and Institute for Building Climatology (IBK). This software is used for analysis and prediction of hygrothermal performance of building enclosures; impact of outdoor climate and pollution on indoor environment; impact of VOC emissions from building materials and indoor furnishings on indoor air quality. This paper introduces the basic mathematic and physic model, boundary condition, climate condition etc, and analyzes the coupled heat and moisture transfer through common structure of building envelop in Shanghai. According to simulation results, main materials of the wall in ITIS have to endure larger range of temperature than ETIS that leads to the life of materials shorter. Capillary condensation occurs on inside surface of the wall easily when RH is larger than 70% and the minimum pore size of finish layer is around 5×10-9m avoiding capillary condensation and mold growth

• Periodical: Advanced Materials Research (Volumes 450-451)
• Pages: 1471-1476
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.450-451.1471
• Online since: January 2012
• Authors: Shui Yu, Xu Zhang
• Keywords: CHAMPS-BES, Coupled Heat and Moisture Transfer, Humidity Field, Temperature Field

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