Simulation Study on the Effects of Relative Humidity (RH) on Long-Wave Radiative Heat Gain in Residential Buildings

Long-wave radiation cooling plays a pivotal role in building thermal design. Utilizing a steady-state method to determine surface heat transfer coefficients across diverse climates can result in discrepancies between the designed and actual cooling performance of a building’s envelope. To evaluate the influence of climate and surface emissivity on building heat transfer during summer, the numerical simulation method was employed to calculate the summer long-wave radiation for nine typical residential buildings across various climate regions. This study assesses the applicable meteorological conditions and distribution range of sky radiation technology. The findings indicate that buildings can effectively dissipate heat through sky radiation when the outdoor relative humidity is below 60% and the summer temperature difference exceeds 12 °C. Analysis of meteorological characteristics across different zones reveals a positive correlation between temperature deviations and sky radiative cooling potential, thereby identifying suitable climate zones for the implementation of sky radiative cooling technology.

This creative work has been published under the Creative Commons Attribution 4.0 International (CC-BY 4.0) license which allows copying, and redistribution as well as adaptation of the original work provided appropriate credit is given to the original author and the conditions of the license are met.