Advanced Materials Research Vols. 860-863

Abstract: Yushu earthquake, Qinghai province seriously damaged the local Tibetan traditional buildings. With the local geographical characteristics and religious significance of the Tibetan traditional architecture, post-disaster reconstruction should inherit the local people's cultural tradition as well as create a positive, intimate space, so that the victims could re-feel the sense of their original homeland. Therefore, with the premise of respecting local customs and traditions, this paper argued that applying the advanced disaster-resistant construction techniques and materials performance into the design could improve the security, stability as well as highlighting the regional characteristics.

Abstract: Resistance to wind erosion enhancement of existing concrete is a new technology to reinforced concrete surface wind erosion, different from the previous wear-resistant research ideas adjustment made of concrete mix, and thick surface wear additional layers, aims to enhance the resistance of concrete surface wind erosion capacity. With fuzzy clustering analysis method, the author analyzes four different types of existing concrete interface reinforcement materials and Come to different effect. Cluster analysis showed that the composite emulsion concrete surface treatment materials can penetrate through the surface penetration means and react with concrete to form a dense network structure, can achieve the purpose of anti-erosion, the best overall performance.

Abstract: The task is solved in connection with Ministry of Industry and Trade project which is involved in development of a complex building programme based on high quality gypsum binder from secondary raw materials. Within one of sub-stages a solution of production of small plaster elements is subject of the project which should present a basic unit for construction of interior plaster partition walls. In the framework of the task a cast of plaster shaped block was carried out using a pilot form of own production. A plaster produced in optimised pilot way from the synthetic gypsum modified with plasticizer and retarding additive was used as a filler binder. After demoulding the produced block was exposed in laboratory environment and tested for setting of selected required properties according to standard EN 12859 (dimensions, density, flatness, tensile strength on bend, pH).

Abstract: Two different thermal insulating materials based on geocement (formulated as Na₂OAl₂O₃6SiO₂20H₂O) were produced as possible environmentally friendly materials, to substitute existing thermal insulation of technological equipment. Expanded perlite was added as filler during the mixing process. The two thermal insulating perlite composite materials were produced in the form of two-component mixture with a ratio of liquid phase (geocement dispersion) to solid phase (perlite) of 3:1.8 and 3:1.0. The developed materials are characterized by: compressive strength of 0.11-0.14 MPa; average density of 296-320 kg/m³; thermal conductivity coefficient of 0.068-0.078 W/mK; adhesion on metal surface of 1.15-1.32 MPa. The measured temperatures on the thermal insulation coatings of technological equipment confirm the effectiveness of the materials developed. These materials, having a thickness not exceeding 3.5 cm, are recommended for application to technological equipment of complex geometric shape at an operating temperature until 1073 K.

Abstract: Several experimental investigations were conducted on the autogenous shrinkage and creep performances of two types of designed self-compacting lightweight concrete (SCLC). In order to explore the difference in long-term performance between SCLC and normal aggregate concrete, normal aggregate self-compacting concrete (SCC) and normal concrete (NC) are also designed in this study. The results indicate that the designed SCLC exhibits lower autogenous shrinkage at early age, even slight expansion during the first 10 days. After 6 months, the autogenous shrinkage of SCLC increases nearly equal to those of normal aggregate concrete. Compared with the reference concretes NC and SCC, the 360-day creep coefficient of SCLC is lower, but the specific creep is higher. It is also found that long-term creep coefficient and specific creep decrease with the increase of compressive strength of SCLC.

Abstract: As a study of natural gas engine, three-dimensional numerical simulations of diesel injection rates were conducted by using AVL FIRE code. And particularly the effects of the injection rates in the pilot diesel jets on the engine combustion and emission were analyzed. It is found that injection rate in the pilot diesel jets plays an important role on the emission, and slow ending rate of the injection keeps lower NO and Soot.

Abstract: Organic Rankine cycle is an effective way to recover low-grade heat energy, working medium is an important part of the cycle, it is one of the important factors that affects its performance. This paper introduces the working principle of organic Rankine cycle, composition, and it analyzes the excellent characteristics of medium, and the current research advances at home and abroad. Finally, aiming at existing problems, it puts forward the research direction and the key of development in the future.

Abstract: Currently, there are many evaluation indexes for gas turbine-based combined cooling, heating and power （CCHP）. In this paper, a multi-objective evaluation index (MEI) model was suggested and weight coefficients were considered in the model. The CCHP system evaluated in this study was composed of gas turbine + heat recovery steam generator (HRSG ) + LiBr absorption chiller. The gas turbine-based CCHP system was evaluated and the component capacity was optimized with the proposed MEI. The study provides a reference for the allocation and operation of gas turbine-based CCHP.

Abstract: Based on the fundamental flow equations of high-pressure gas pipeline, the numerical solution for unsteady-state flow was studied with the Central difference scheme. Considered the energy equation and urban gas regular, the problem of low calculation precision caused by ignorance of the energy equation was solved. During the variation of gas consumption with time, the dynamic simulation program was generated. Finally, a numerical example of engineering application was presented .

Abstract: Combustion reaction between silicon powders and nitrogen in transport bed was studied. The reaction temperature ranged from 1523 to 1653 K, and the reaction time ranged from 0 to 2.7 min. The phase compositions, morphologies and chemical composition of the products were analyzed by X-ray diffraction, scanning electron microscopy and O/N determinater, respectively. The experimental results showed, in the case of silicon powders with particle size of 2.2 μm, the conversion rate of silicon was 61.9% at reaction temperature of 1653 K and reaction time of 2.7min, and the products mainly comprised amorphous silicon nitride powders.