Numerical Prediction the Long Term Moisture Damage Within the Brick and Wood Structure Considering Wind Driven Rain in the Hot and Humid Southern China Area

The climate is hot and humid in the southern China area, building envelope is usually affected by rain erosion in this area. The coupled heat and moisture transfer model applicable to high humidity condition is established and validated. The influence law of wall transferred cooling load, mold growth and wood decay exposed to wind driven rain (WDR) are examined through five years of numerical simulation in the representative city of Guangzhou. Compared to the case of ignoring WDR, when considering the impact of WDR, the sensible cooling load transferred by the east, south, west and north orientation wall increased by −14.0%, −29.6%, −16.3% and − 6.1% respectively, the latent cooling load transferred by the four orientation walls increased by 94.4%, 179.3%, 84.2% and 32.6% respectively. The highest value of mold index at the interface between the four orientation walls and pine board is predicted to separately increase 37.1%, 45.5%, 17.9%, 30.4% compared to the case of ignoring WDR. The wood decay mass loss rate at the interface between the four orientation walls and pine board are 1.91%, 3.63%, 0 and 1.58% respectively, but there is no mass loss of wood decay when the impact of WDR is ignored.