Wei W.,China Building Material Test and Certification Group Co.
Key Engineering Materials | Year: 2014
Tris(hydroxymethyl)ethane (PG) as a phase change material, micro-porous xonotlite (CS) as matrix, PG/CS composite PCMs were prepared by melt-soaking method, and the effect of micro-porous structure of xonotlite on heat absorption capacity, bending strength and insulation performance of composites, and the exudation of PG was studied. Otherwise, for the work environment and characteristics of propulsive device of vehicle, this paper explored the feasibility that phase change materials (PCMs) worked as the insulation material in short-time insulation system of the vehicle. Experimental results show that, when the most probable pore diameters of xonotlite was not less than 63nm, the composites presented better and almost same absorption capacities of matrix (CS) to PCM (PG) in different composites; when up to 85nm, the composite exhibited the lowest leakage rate (less than 5%), the optimal mechanical property and thermal insulation performance. This Study proposed a new idea for the design of the insulation material in the thermal protection system of propulsive device of vehicle. © (2014) Trans Tech Publications, Switzerland.
Zeng C.,China Building Material Test and Certification Group Co. |
Huang Z.,University of Science and Technology of China
Key Engineering Materials | Year: 2014
The total bauxite reserves of China are about 3.7 billion tons, however the principal and the first-class bauxite reserves account for only about 20%. A large number of coal gangue was accumulated on the surface of earth, which not only encroaches land but also pollutes the environment. In this study, low-grade bauxite with alumina content of 53.18 wt.% originating from Shanxi Yangquan and coal gangue with alumina content of 38.07 wt.% originating from Shanxi Datong were used to synthesize mullite materials. Bauxite and gangue were mixed by the ratio of 1 to 1. The ingredients were prepared according to the alumina content of 45.63 wt.% and 70 wt.%, by adding a certain amount of industrial alumina, respectively. The samples were sintered at 1350°C to 1600°C after being milled, dried and formed. The influence of alumina content and sintering temperature on the phase, microscopic morphology and properties of samples were discussed. The results show that, the main phases of the sample with the alumina content of 70 wt.% were mullite (more than 60 %) and corundum after being sintered for 4h at 1600 °C. The phenomenon of columnar mullite and granular corundum staggering had been observed. The bulk density and the bending strength of sample is 3.21 g/cm3 and 220.73 MPa respectively. © (2014) Trans Tech Publications, Switzerland.
Zhang L.,South China University of Technology |
Yao X.,South China University of Technology |
Zang S.,China Building Material Test and Certification Group Co. |
Han Q.,South China University of Technology
Materials and Design | Year: 2015
During airplane related accidents, the transparent polyurethane interlayer is finding new applications in the aircraft protection as an interlayer of windshield to enhance structural survivability under impact loading. Using dynamic mechanical analysis, Instron testing system and low impedance Split Hopkinson Tension Bar (SHTB), dynamic tensile response of a transparent polyurethane interlayer is studied experimentally under wide ranges of strain rates and temperatures. Based on the constitutive theory and the experimental data, thermal-viscoelastic Zhu-Wang-Tang (ZWT) constitutive model is employed to describe the tensile response of the polyurethane interlayer. The experimental results also reveal the time-temperature equivalence relation for the polyurethane interlayer. Strain rate and temperature are put together to a unified parameter by introducing a dimensionless parameter, and a unified curve reflecting the time-temperature equivalence relation is obtained. © 2014 Elsevier Ltd.
Yuan X.,China Building Material Test and Certification Group Co.
Key Engineering Materials | Year: 2012
Through collecting and analyzing thermal data from on-site testing of more than 30 cement plants, combining with design indicators of production line and control parameters in practical operation, the paper has summarized 4 first level, 5 second level and 133 third level energy efficiency evaluation indicators of cement enterprises after an in-depth study on the main factors influencing coal and power consumption of cement plants. On this basis, an energy efficiency evaluation system of new suspension preheater cement enterprise is to be established in China. It is expected to provide cement enterprise the basis of mastering the level of energy management and checking questions of energy utilization, to play guiding functions in settlement of energy-saving measures, development of energy-saving potential and reduction of energy consumption. © (2012) Trans Tech Publications.
Liu Z.,China Building Material Test and Certification Group Co. |
Bao Y.,China Academy of Building Research
Advanced Materials Research | Year: 2011
Building-integrated photovoltaics (BIPV) is a relatively recent new application of photovoltaic (PV) energy technologies whose energy output is affected by many design-related factors including PV module technologies, installation orientation, tilt and shadow range of solar panels. The shading analysis of a residential house's PV roof in Beijing was conducted by using building analysis program Autodesk Ecotect 2010. Analysis result shows that there is no shadow on the PV roof from 9a.m to 4p.m in winter solstice when the solar altitude angle reaches minimum, which ensures almost no shading losses for the PV modules over the year. The differences in monthly energy output were compared in the case of different installation tilt of solar panels and PV module technologies. Finally, the contribution to the building energy of the PV roof was discussed. The results show that appropriate design and selection of PV modules can compensate for the energy requirements for building heating and cooling to some extent. © (2011) Trans Tech Publications, Switzerland.