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On account of radiant time factors method, this article presents a computed way of floor radiant cooling loads using radiant time factor procedure program to compute floor radiant time factors and to get floor radiant heat gains by test data collected within 24 h, then dynamic floor radiant cooling loads could be acquired by matrix operations. Five experimental conditions are selected to validate the calculated results. The experimental results indicate that the crest value errors between room-cooling loads and separating cooling loads about each condition are among the range-3.2% to 4.7%, and the mean value errors are less than 6.1%. The floor radiant cooling loads decrease and delay according to the changes of floor radiant heat gains. Crest value errors between measurement cooling loads and calculation cooling loads are among the range-1.8% to 2.3%, and the mean value errors are not more than 3.2%. Taking radiant time factor procedure program to compute corresponding building room floor radiant time factors with three types of building envelope, floor radiant cooling loads' characteristics would be obtained under two conditions such as different radiant time factors and different radiant heat gains. So the room floor radiant time factors are calculated by radiant time factor procedure program, and building room floor radiant cooling loads can be computed.

Radiation heat and convection heat exist on stratified air conditioning zone building surfaces in large space, and they have significant impact on cooling load calculation and thermal comfort analysis. Actually, heat transfer in large space is usually under non-steady condition. Based on an actual large space, a 1:4 scale model experiment rig is built as research object, which has: typical sloping ceiling structure, columnar low supply air, middle return air, inner surfaces periodic heat flow simulation system, heat measurement, and control system. For stratified air conditioning zone building surfaces in large space, radiation heat transfer calculation model is presented based on Gebhart radiation model and radiation heat is calculated by matrix calculation. Convection heat transfer calculation formula is presented based on inner surfaces temperatures and indoor air temperatures. Taking two periodic heat flow experiment conditions, building surfaces temperatures and indoor air temperatures of stratified air conditioning zone in large space were collected, taking model calculation program to compute dynamic radiation heat and convection heat. The result indicated the dynamic characteristics of radiation heat and convection heat of stratified air conditioning zone building surfaces in large space. It provided some important information for dynamic heat transfer research in stratified air conditioning zone building surfaces in large space.