Experimental Analysis On The Thermal Response Characteristics Of Radiant Floor Heating Systems

With the wide application of hot water floor radiant heating system, how to effectively regulate and run the floor heating system to meet the conditions of the comfort of room thermal has been increasingly prominent issues.The heat transfer process of floor radiant heating system is different from the radiator heat transfer process. Indoor air temperature has obvious hysteresis under conventional regulation systems.In order to understand the impact of factors and changes of floor heating system thermal response characteristics, the research firstly analyzed the heat transfer mechanism of heating floor radiant system, initial grasp of the factors affecting floor heating system thermal response characteristics, which presents basis for determination of experimental case.This study carried out some experiments and explored the time response characteristics of floor surface temperature and indoor air temperature using the on-off control heating method with initial indoor air temperature, water temperature, tube pitch and outdoor air temperature varying. The results can provide basic data reference for building and simplifying of the calculation model of radiant floor heating system and operation of energy-saving.Even though the experimental conditions were limited, while in order to get the calculation method of the temperature with the radiant floor heating system, this study established the transient heat transfer model of heating surface by means of the numerical simulation method and got multiple regression of the simulation results about the supply water temperature, tube pitch and the surface temperature under buried layer thickness. This can provide methodological reference for quantitatively calculating the process of surface temperature under the condition of radiant floor heating system.This study shows that the floor surface temperature increases exponentially with time in the process of heating. Under on-off control operation mode with outdoor air temperature in range of-4℃~ 3℃ and continuously heating for 2~4h, the inner surface temperature of external walls ranges from 16.8 to 19.4 ℃, and the inner surface temperature of interior wall ranges from 18.9 to 20.9℃, which is similar to the indoor air temperature. Numerical simulation and multiple regression methods of heating the surface temperature calculation process can be solved exactly under the control of the operating mode, the room air temperature changes to a lesser extent, the surface temperature of the heating process. The results can provide basic data reference for the optimized design of radiant floor heating system and operation of energy-saving.