Applied Mechanics and Materials Vols. 190-191

Abstract: Tower crane is a widely used lifting machinery which can be produced by several domestic manufacturers. The study on static characteristics of tower crane is widely engaged in nowadays. However, the analysis based on advanced CAE techniques is seldom used. Therefore, this paper uses ANSYS to analysis the characteristics of tower crane and the final results are well validated.

Abstract: In this paper, the hydraulic-bulging assembly process for the stator and can is simulated by using ABAQUS/Explicit. Five different models of the stator and can component were developed. The processing parameters are analyzed and compared based on the simulation results. The simplified model with higher precision and less computational time is attained and will be used in the future process optimization.

Abstract: Hot rolling is a basic metal forming technique that is used to transform preformed shape into final products of forms more suitable for further processing. As the hot stock progresses through the forming surfaces, the shape eventually reaches a constant state. With the assumption of forming process has reached steady-state condition, a simulation technique based on elements re-meshes has been constructed to analyze the H-beam metal hot roll process. The technique includes the following approaches: the solution was halted as soon as the steady-state criteria were met, and the plane of elements, which first satisfied the steady-state criteria were written to database, SSES for short; a two-dimensional model was created to model the hot stock cooling between the two roll passes and a geometric part was generated and meshed with quadrilateral elements to transfer the nodes temperatures; a new three-dimensional model extruded from the two-dimensional model was constructed to model the next roll pass with the transfer of nodes temperatures and element integration points equivalent plastic strain(PEEQ), identifying the plastic deformation extent for the classical metal plasticity models, from the new two-dimensional model and the first three-dimensional model respectively. Gleeble-1500 tester is used to get the true stress and true plastic strain data for modeling the yield behavior of material Q235. The effectiveness of the simulation technique has been proved by a simulation of 11-pass H-beam rolling process.

Abstract: In the rapid development process of cylindrical drip emitter, the traditional CFD analyzing method was generally carried out based on the planar model of the cylindrical labyrinth channel. However, the result obtained by this method was obviously different with the experimental data. In this paper the cylindrical prototype of the labyrinth channel was proposed and the CFD analysis was carried out based on the hexahedral mesh of the cylindrical labyrinth channel to solve this problem. Then the flow rate and the anti-clogging performance of the emitter were predicted based on the stereo prototype of the labyrinth channel. Consequently, the simulation results were verified and the cylindrical drip emitter was finalized according to its hydraulic performance experiment.

Abstract: Ontology library is one of the cores of the intelligent IETM system; it is widely used in intelligent information retrieve, e-business, and network collaboration. Information retrieval and graphical representation of follow-up operation should be based on the ontology, many applications require the integrated query from related information resources, which arises the problem of semantic interoperation in heterogeneous information resources. There are many complex factors in integrating them, because different ontology creators adopt different semantics from his individual view. This paper proposes the framework of ontology integration though analyzing the problems in the process of ontology integration. The application results show that the proposed cycle evolution of ontology construction method to solve the IETM domain ontology building and storage problems.

Abstract: Fully-welded ball valve has been applied in large oil and gas pipelines, and its quality is directly related to the safety of the transportation of national energy. The wall thickness of 48″600lb ball valve is greater than theoretical design thickness. In this article, FEM software was used to design minimum wall thickness using linear stress analysis method. Though changing wall thickness under design pressure, the minimum wall was 85mm which calculated by linear stress analysis method can provide theoretical support for practical engineering application

Abstract: Density functional theory (DFT) calculations were performed to investigate the structures of chloro silsesquioxanes Si2nO3nCl2n (n=1-5). Our study focuses on the structures, stabilities, and electronic properties of the chloro silsesquioxanes. The large HOMO–LUMO gaps, which range from 4.54 to 7.39 eV, imply optimal electronic structures for these molecules.

Abstract: A new building type- cavity construction system with trombe wall was proposed. Solar thermal storage wall was used to heat air gap between glass and wall. Updraft passed through hollow floor and supplied heat to upper room. Heat transfer model was built and numerical simulation of this kind of buildings was done. The results showed that cavity construction system with disconnected trombe wall had appropriate air- flow organization and uniform heating effect, which had better serviceability to high-rise buildings.

Abstract: It has previously been reported that when a fatigue crack grows in ferromagnetic materials, abnormal magnetic signals are spontaneously emitted, which can provide a powerful tool for fatigue crack life prediction. However, there is no physical model yet available to explain the mechanism for the formation of these self-emitting magnetic signals. In the present research, tension-tension fatigue tests of center-cracked sheet specimens were performed. The variations in the normal component of the self-emitting magnetic signals, Hp(y), on the surfaces of the specimens were measured during the fatigue test. The differences in peak-to-peak value, Hp(y), before and after failure of a specimen, were characterized. Consequently, a physical model based on magnetic charge was proposed, which was in good agreement with the experimental results. The model is helpful for understanding the inherent mechanism of the self-emitting magnetic signals.

Abstract: The asphalt pavement of cement concrete bridge belongs to thin structure, its high temperature stability is an important indicator. Using self-made heating system, through test on full scale linear track, conduct on-site rutting survey, and supplemented by the identification of drill core samples and laboratory test of pavement’s rutting, research on asphalt pavement's high temperature stability on the bridge. The research results not only provide a strong basis to the concrete bridge asphalt pavement mix design, but also provide some reference to similar engineering practice.