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The influence of surface polaritons on spectral energy flux at different temperatures or distances to the surface of a plate was analyzed. The relations of the net heat flux between two parallel plates with the material type were also discussed. The results demonstrate that the effect of surface polaritons is dominated in the spectral energy flux at 300 K when the distance is decreased to 100 nm. In addition, the intensity of surface polaritons increases with the temperature. The net heat flux between two parallel plates has a nearly linear relation with the temperature and is closely related to the material type. It reaches up to 2.792×107 W/m2 between two SiC plates, approximately 3~6 orders of magnitude larger than that between two different materials. However, the net heat flux between SiC and Al is merely 2329.7 W/m2, even smaller than the result calculated by the classical stefan-boltzman law between two blackbodies.

In this paper, the authors analyzed effects of the factors, such as the air mass flow rate, the geometric dimensioning of the inner and outer combustion tubes and the thickness of the radiator, to the performance of the combustion-end radiator system. The result shows that optimal performance will be achieved when the combustion power is 1kW and the air mass flow rate is 5 times higher than the requirement for the complete combustion of CH4. On this basis, the effect of the geometric dimensioning to the combustion-radiator system is discussed. The performance of the combustion-radiator system is the best when the inner diameter of inner tube is 24mm, the length of the combustion tube is 40mm and the radiator thickness is 1mm. In this condition, the average temperature of the radiant surface, the radiant power density of the radiator and the combustion efficiency are 1530K, 9.41W/cm2 and 47.3%, respectively.

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Power line communication is popular at indoor communication and smart home applications, which face a harsh using condition that is of bad impedance match, large signal attenuation, unexpectable noise and channel high time variation. These difficulties set a high threshold for power line communication technology and improve the communication channel simulation to an important place. To predetermine the performance of power line communication productions, a narrow-band communication simulation platform was developed. This platform is based on low voltage communication channel model, and can update the system parameters using on site measured data, which could get a match with the real application environment. Main channel characteristics, such as noise, signal attenuation and frequency respond could be simulated on this platform. Noise generation frequency range of this platform is 0~120MHz, attenuation frequency range is 0~4GHz and attenuation range is 0~120dB. All performance indexes can well cover the measurement boundary of power line communication.