In order to get the influence of the water supply temperature on the ability of supplying energy, the computational results with the water supply temperature are 20°C, 15°C, 10°C, 50°C, the ambient

temperature is 35°C and the indoor air temperature is 28°C, respectively, are analyzed and discussed.

Fig.9 and Fig.10 represent the floor temperature distribution contrast curve of different medium temperature and the wall temperature distribution contrast curve of different medium temperature, respectively. It can be seen from Fig. 9 and Fig.10 that temperature distribution curves under supply cooling are opposite to the heating. The floor temperature has a minimum value at the embedded pipe; the wall temperature distribution is monotonically increasing.

The computed results of cooling ability with different medium temperature are listed in Table 5. Table 5 indicates that the water supply temperature has great impact on cooling ability. Combined with Table 3 we can see that, the total thermal flux in summer is lower than in winter because of the total thermal flux depends on the temperature difference between water supply temperature and indoor air temperature.

Form Table 5 we can see that, the energy supply of floor is higher than the wall and the energy supply of floor accounts for 60% of total energy supply of the system whether winter or summer. Above phenomena is determined by the location of the embedded pipe and the thermal conductivity of the materials in the heat transfer area.

3. Conclusions

In the paper, a numerical investigation on the new type radiation energy supplying system is performed. The following conclusions can be made:

1. The capacity of the system is affected by diameter of embedded pipe, location of embedded pipe, water supply temperature. The capacity of the system increased with the increasing of the diameter of embedded pipe, but the cost of the system increased also; the ability of supplying energy of floor was approximately 60% in the total capacity of the system; the increased of the water supply temperature could improve the ability of supplying energy of the system.

2. The practical application of the system shows that the cooling and heating energy need have enveloped energy saving buildings with 40°C heating medium in winter and with 10°C cooling medium in summer. The heat transferred through the floor occupied 60% of the total in summer.

3. The system can prevent condensation on the floor surface in the absence of dehumidification system, because of higher water temperature in summer; the system can prevent surface crack of floor or wall, because of lower water temperature in winter

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