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Aerated concrete (AC) was incorporated with micro-encapsulated phase change materials (PCMs) to form a novel PCM-composite AC with improved thermal storage capacity. RT25 paraffin was selected as the PCM and the composite materials were prepared by adding micro-encapsulated paraffin as an ingredient at various loadings. The effective thermal conductivity of the composite samples was measured at both 17 ºC and 35 ºC, while the paraffin was in solid and liquid phases, respectively. The volumetric heat capacity of the composites were also measured. Results showed that both the thermal conductivity and volumetric heat capacity increase upon adding the micro-encapsulated paraffin. However, they were found to decrease when further increase the paraffin loading. The maximum thermal conductivity and volumetric heat capacity were enhanced by approximately 35% and 30% when the paraffin loadings were 1% wt. and 3% wt., respectively. Since the increase of thermal conductivity leads to the deterioration of the thermal insulation performance, the composite samples with 3% wt. micro-encapsulated paraffin with lower thermal conductivity but the highest volumetric heat capacity was exhibited to be more appropriate.

The ultrafine CaCO3 was usually produced by wet chemical synthesis technique currently. The solid-liquid separation techniques of mechanical filtration and two-stage thermal drying were needed to separate the ultrafine powder from the CaCO3 slurry. A new technology of thermo-compression filtration was taken to dispose the ultrafine CaCO3 suspensions for purpose of simplifying the traditional producing technique in this paper. The thermo-compression filtration not only combined the process of mechanical filtration and thermal drying on one single filter press, but also saved energy because of its non-phase-change thermo-compression drying characteristic. The external heat energy was used to offer assistant thermo-motive, but not to vaporize all of the moisture in the saturated cake. The experimental results indicated that the thermo-compression filtration was much more effective than mechanical filtration or thermal drying respectively. The moisture content of filter cake after thermo-compression drying was about 18.75%~21.89%, much lower than that after mechanical filtration, about 25.5%~28.5%. Furthermore, to keep a relative higher temperature of drying plates when mechanical filtration process was an available method to obtain the product with lower moisture content, but use a minimum working time.

NTS6ZLCz-129 dual-fuel turbocharged and intercooled engine durability test at 1000h, fuel pump shaft fractured. Fracture analysis, chemical analysis, microstructure examination and finite element stress analysis were carried out on the fractured shaft. The analysis result showed that the shaft fracture cause is forging fold. By improving the forging process, the forging fold was solved, and the durability test can be carried out smoothly.

This paper studies the influence of flash economic system on performance of refrigeration unit using Refrigerant R290. Theoretical analyses of refrigeration system with flash type economizer are carried out firstly, which provide theoretical basis for working parameters. Under different evaporation temperature, influences of supply pressure on the refrigerating capacity and COP are studied and verified through experimental. Experimental results show that, using the economizer can effectively improve the cooling capacity and COP, and achieve the effect of saving energy. With the increase of supply pressure, refrigeration capacity of refrigerating unit and shaft power decreases gradually and the refrigeration coefficient rise first and then drop, to determine the best economic position.