Papers by Keyword: Influencing Parameters

Abstract: The Space Curve Meshing Skew Gear Mechanism (SCMSGM) is an innovative gear mechanism proposed by the present authors. In this study, the contact ratio for the SCMSGM is deduced. By analyzing the eight influencing parameters on the contact ratio for the SCMSGM, the principal influencing parameters on the contact ratio for the SCMSGM are obtained. This study provides a theoretical basis to calculate and select the contact ratio for the SCMSGM.

Abstract: The value of peak gas production and the time when it reaches are two important marks for coal bed methane (CBM) well’s gas production curve. This paper takes M CBM gas field of A country’s B basin as actual production instance. Firstly, based on the CBM producing mechanism, the existence reason of peak gas rate is analyzed; secondly, the influencing factors of the value of peak gas production and the time when it reaches is studied by numerical simulation method. And sensitivity order of the influencing factors is obtained. The study results indicate that: the value of peak gas production has positive correlation with properties: permeability, gas content, coal bed net pay and gas saturation; while negative correlation with desorption time and cleat porosity. And the strong to weak intensity of sensitivity is permeability, gas content, desorption time, net coal bed pay, cleat porosity, gas saturation. The time when peak gas production reaches is markedly influenced by the value desorption time and cleat porosity, the smaller of the two parameters, the shorter of the time when peak gas production reaches.

Abstract: Polystyrene microcellular foams blowing with supercritical CO₂ were prepared with a novel polymer foam processing simulator. Key parameters influencing Polystyrene cell morphology were investigated. The effect of processing temperature and saturation pressure on cell morphology was observed by scanning electron microscope and the average cell diameter and cell size distribution was calculated. The results show that the cell density decrease and cell size increase with the increase of foaming temperature. The cell density increase and cell size decrease with the increase of saturation pressure. And the cell size distribution shows a narrow distribution at lower foaming temperature and higher saturation pressure.

Abstract: The excessive long-term deflections of a long span continuous girder bridge may induce vehicles to move unsafely and hazard to the bridge operation, thus to limit the development of this bridge type. In this paper the main parameters influencing the long-term deflections of a continuous rigid-frame bridge, such as pre-stressed losses, mass distribution of the box girder and Young’s modules of concrete etc., were investigated. With the establishment of the finite element model of a real bridge and the premise of describing mechanism of each parameter, detailed parameter sensitivity analysis of long-term deflections were carried out with numerical simulation method. The results of this study may help to understand the main mechanism about the long-term deflection of continuous rigid-frame bridge and provide some reference for the wide use of this type of bridges.

Abstract: In this paper a numerical model for fire resistance analysis of bar-reinforced concrete filled steel columns with square and circular cross-sections have been put forward. The model has been validated by testing results. There is a good agreement. Used of the theoretical model, the relations between the fire resistance and various parameters have been analyzed. On the basis of that, formulas for the calculation of the fire resistance of bar-reinforced concrete filled square and circular steel columns under ISO-834 Standard Fire Curves are developed respectively. The calculated results have a good agreement with those of mechanic model and test.

Abstract: In order to manufacture a workpiece fulfilling specified requirements with the lowest possible weight, it is crucial to be able to work with a variety of materials and to combine them accordingly. The production of profiles based on hybrid materials demonstrates such an approach. The continuous and selective reinforcement of aluminum profiles with metallic elements like steel wire and steel wire ropes by composite extrusion is being investigated within the scope of research of the Transregional Collaborative Research Center (SFB/TR10). A stable production process for composite profiles with embedded continuous reinforcing elements was developed during the research work. In this paper, the process principle is shown and an overview of the special tools is given. Furthermore, the temperature and the strand speed as influencing factors on the final state of the composite are analyzed, based on real size experiments using a 2.5MN and a 10 MN extrusion press.