Abstract
Recent building practice requires that buildings not only conserve energy but also provide a healthy and comfortable environment for the residents. However, most of the simulation software used to predict the temperature, humidity, and heating and cooling load of buildings does not take into account the human sensations under the non-uniform environment and contact thermal conductance such as the radiant heating and cooling system. A Heat, Air, and Moisture (HAM) simulation software, called THERB for HAM, has been developed for estimating the hygrothermal environment inside buildings. This software encompasses the complete set of HAM features, including the principles of moisture transfer within walls. The software can estimate the temperature, humidity, and the sensory index “COMSET*,” based on the hygrothermal balance of the human body, and the heating and cooling load for multiple-zone buildings and wall assemblies. The heat and moisture transfer models used in THERB, such as those for conduction, convection, radiation, and ventilation, are based on detailed phenomena describing the actual building physics. This paper highlights the features of the heat transfer models used for the detailed calculation of a hydronic floor-heating system. The accuracy of the calculations is verified by comparison with the monitoring results of a test house equipped with a hydronic floor-heating system. Furthermore, energy simulation for space heating and floor heating is performed to evaluate the energy conservation of both systems, based on the sensory index “COMSET*.”
