Applied Mechanics and Materials Vols. 84-85

Abstract: The chassis of disc vibration dryer is easy to be destroyed during operation. Aimed at this problem, this paper analyses harmonic responses of dryer vibration system based on ANSYS. The curves both in the relation between the displacement and the frequency and in the realtion between the stress and the frequency about several special positions in which the chassis is easy to be destroyed were obtained. The analyses to curves provided a basis for this kind of dryer's structural design, improvement and maintenance.

Abstract: In order to provide an experimental machine for elastic bungee jumping ropes, a prototype of experimental mechanism was designed, and its principles were analyzed. A dimension synthesis method of the experimental mechanism based on the particle swarm optimization (PSO) was brought forward. The aim of optimization was to find the optimized parameters of the mechanism by which the elastic bungee jumping ropes were pulled at the minimum swing angle. An optimization program of the PSO algorithm in the Matlab environment was developed and the optimal calculation was done. The result proved the validity of the algorithm. The calculation result showed that the optimal algorithm made the elastic bungee jumping ropes pulled at the minimum swing angle of only 8.783 degree, which was better than that of the handwork drawing method used by an engineer, so the parameters got by the PSO method can

Abstract: The new method for separating drained coal bed methane (CBM) is based on gas hydrate formation. The thermodynamic parameters of incipient hydrate formation for the CH₄-N₂-O₂-THF-H₂O system were carefully determined. After establishing equilibrium state of three-phase coexistence, CH₄ concentrations of vapor phase and that of hydrate phase were determined by GC. The results show that the higher the THF concentration, the larger the CH₄ concentration in hydrate phase and the partition coefficient. It can provide the reference for seeking the optimal promoters in the hydrate formation process for the mixed gas.

Abstract: Huainan mining area for the serious outburst Xinzhuangzi B4 soft coal mines in high stress, In order to improve the mining face outburst forecast accuracy, reduce the amount of works against sudden, With the theoretical analysis, lab tests and field trials of the combination of a variety of means, Of pilot area received 56204 B4 coal mining Face of sensitive indicators of the critical value: S₀＝4.0kg/m,K₁=0.3 mL/(g·min^1/2), The test area 1380m mining engineering application results show that the face is not obvious prediction accuracy rate of 100%. Study to determine the indicators and their threshold reasonable and effective, in line with the actual situation of test area, with a certain application value.

Abstract: For the excellent properties, super-hard tool material has received much attention from researchers. The development of super-hard tool material for high-speed cutting could brought high machining quality and surface precision. For an engineer, adopt high performance of tool material, for example wearing resistance, high stability of PCD (polycrystalline diamond) and PCBN (poly cubic boron nitride) can get more information for obtaining higher finished surface quality that cannot acquire just by common cutting process. This paper introduces super-hard cutters materials (PCD and PCBN) development, and discusses several material properties. The features of materials used in different cutting fields are given.

Abstract: The pyrite smelting slag as industry waste residue was always fully studied in the present research. Due to the complexity of the property of the waste residue,which the environmental hazards of has been discussed in the experiment. Firstly, the complex composition of the waste residue and the primary contamination of heavy metals which included the Copper, Cadmium, Zinc, Nickel, Lead, Chromium and Arsenic usually were determined by XRF scanning. the result of XRF scanning also showed the value for reuse of the waste residue.Secondly,the test investigated the leaching toxicity of the waste residue,the results indicated that the heavy metal of the residue was in low concentration ,in the other words,the slag lixivium was in the range of the required standard, the pyrite smelting slag does not belong to hazardous wastes. The Copper, Zinc and Nickel had not exceeded the standard limit,however, the waste residue could contaminate the surrounding environment if it didn’t been disposed with proper methods.based on the further study, the residue belongs to Class Ⅱ General Industrial Solid Waste and the main phase present in pyrite smelting slag were silicon oxide. Thirdly, through XRD spectra analysis,it can be indicated that waste oxides and sulfate facies were the major phases of heavy metals. So,in order to prevent these potential risks,some effective protection measures should be taken.

Abstract: Hydrological simulation is the basis of water resources management and utilization. In this study, Soil and Water Assessment Tool (SWAT) model was applied to Jin River Basin for hydrological simulation on ArcView3.3 platform. The basic database of Jin river Basin was built using ArcGis9.2. Based on the LH-OAT parameter sensitivity analysis, the sensitive parameters of runoff were identified, including CN2, Gwqmn, rchrg_dp, ESCO, sol_z, SLOPE, SOL_AWC, sol_k, Gwrevap, and then model parameters related to runoff were calibrated and validated using data observed in weifang, yifeng, shanggao and gaoan hydrological stations during 2001-2008. The simulation showed that the simulated values were reasonably comparable to the observed data (Re<20%, R² >0.7 and Nash-suttcliffe > 0.7), suggesting the validity of SWAT model in Jin River Basin.

Abstract: Two-phase mechanically pumped cooling loop (MPCL) has emerged as a highly effective means for dissipating large amounts of heat from a small heat transfer area and provided a robust solution for significant design with flexibility, precise temperature control, and is othermalization. In this paper, the attempt of design optimization of the work fluid is introduced, by employing thermal simulation analysis with SINDA/FLUINT.

Abstract: In this paper, the characteristics of a special condenser for space thermal control were investigated. In order to compare the thermoresistance getting from different formulas, both single-phase and two-phase fluid in the condensers were calculated. The results present that the thermoresistance has a uniform value for single-phase and a large variance for two-phase fluid. Therefore, experiences were performed to clearly comprehend two-phase fluid performance in the condenser. From the experiments, it demonstrates that the condenser thermoresistance has decreased with the heat load increasing under the same mass flow rate. The analyzes points out that the thermoresistance caused by contact plays a more importance role for the condenser heat rejection capacity.

Abstract: The two-phase mechanical pumped cooling loop is a promising thermal control system which is just like a heat pipe to realize heat extraction from ener-electrical equipment by phase change efficiently. In order to apply this technology for the space thermal control systems, transient tests have been performed to clearly comprehend its performance and to characterize operation in different conditions. Special attention has been paid to the system dynamic working characteristics under different conditions such as variation heat load and mass flow. According to the experimental findings, the transient liquid transfer between the main loop and accumulator was analyzed to explain the transient phenomena during the experiments. From the experiments, it is demonstrated that when mass flow increases or heat load decreases, work fluid would flow out of the accumulator because of vapour quality changing. On the contrary, when mass flow decreases or heat load increases, work fluid would flow back to the accumulator .The paper also presents that accumulator is just like the “brain” of the system and each action of the vapour-liquid interface would cause the temperature or pressure change of the evaporator.