Advanced Materials Research Vols. 347-353

Abstract: A kind of form stable phase change material (PCM) based on expanded perlite, paraffin, urea formaldehyde hybrids is prepared by using vacuum-impregnation process. This kind of form stable PCM is made of paraffin as a dispersed phase change material and expanded perlite as a supporting material, and urea-formaldehyde resins as membrane materials to be applied to the porous surface of expanded perlite(EP). The structure of urea-formaldehyde resins(UF) being prepared is characterized by Fourier Transform Infrared Spectrophotometer(FT-IR). Hybrids’ thermal stability, latentheat and morphology are characterized by the thermogravimetry analysis(TGA), differential scanning calorimeter(DSC) Method and scanning electronic microscope(SEM), respectively. The FT-IR and SEM curves show that urea-formaldehyde resins have already been formed. The TGA analysis indicates that the form-stable phase change material has very good thermostability under working atmosphere. The application of DSC not only studies the appropriate curing time of UF，but also indicates that the form-stable PCM that has been prepared has more stable thermal energy storage performance than the traditional one.

Abstract: The purpose of this paper is to solve problems in the development of energy saving green building in China. After the careful analysis of energy consumption today, factors affecting energy saving building was made, causes for problems were induced. Combined with the existing conditions, energy-saving building technology was proposed. The result of the research could play a positive role in promoting development of green building in China and solving the practical problems.

Abstract: In order to investigate the effect of variable valve timing on engine power performance, fuel economy performance and emission performance quantitatively, proceed to optimize it, a high speed diese Specific Fuel Consumption, quantity of NOx and Soot, mass of fresh charge were calculated by 3-D CFD method l engine contains variable valve timing system (VVT) was researched. The effective power, at 6 speeds conditions which valve timing parameters were modulated. A method of calculating CRG was suggested. The results indicate that exhaust advance angle has a little impact on sweep and emission performance, but a big impact on ventilation losses. The optimum exhaust advance angle should be increased as engine speed rises. Increasing intake lag angle in low engine speed could increase coefficient of charge, thereby increase power performance and fuel economy performance. Comprehensive performance could be increased by decreasing intake delay angle under high speed.

Abstract: The basic working principle of a Flywheel Energy Storage System (FESS) is introduced. From the angle of failure detection means and fault types, the status and deficiency of the research on FESS Fault Diagnosis (FD) and Fault Tolerant Control (FTC) are reviewed. Moreover, the FESS FD and FTC methods are analyzed in detail. Finally, the deficiency, research hotspot and development trends of FESS FD and FTC are discussed.