Advanced Materials Research Vols. 631-632

Abstract: This paper reports numerical and experimental investigation of capillary burst valve and siphon, which were used in the centrifugal microfluidic systems widely. The simulation model is based on the solution of the minimum energy problem by the Surface Evolver software. In contrast to the solution of meniscus equilibrium equations, it can provide the appropriate boundary conditions for the microvalves with a hydrophilic flat cover. As an experimental verification, a centrifugal microfluidic device based on PDMS and glass was fabricated by soft lithography. The simulated results agree well with experimental data. The technology is useful for the design of microfluidic systems with complex wetting characters and geometries.

Abstract: Experimental researches were presented on dynamic characteristics of Q235 steel cylindrical shell impacted-explosive laterally by 75g cylindrical TNT dynamite at the center．The dynamic response was obtained under different distances with different setting ways of explosive sources．By means of an explicit nonlinear dynamic finite element computer code LS-DYNA，the nonlinear dynamic response process of cylindrical shell subjected to laterally explosion loading were numerically simulated with ALE coupling method. The numerical simulation results were in good agreement with experimental data. The results provided important reference for the blast-resistant properties analysis and safety assessment of oil-gas pipes safety.

Abstract: A new non-contact method for predicting the basic oxygen furnace(BOF) end point carbon content is proposed in this study. A model applying the flame spectrum of the converter vessel mouth is constructed to carry out the prediction. This model consists two parts, viz. a classifier based on support vector classification to classify the whole period of one BOF heat into two main phases, and a relevance vector machine working at the posterior phase to predict the carbon content. Compared with current non-contact methods of end point carbon content prediction, the proposed method can make better use of the information of the flame of the converter mouth. Simulations on industrial data show that this method yields good results on the classification as well as end point carbon content prediction.

Abstract: Objective To compare the biomechanical properties of two lag screws proximal femoral nail(PFN) when they are placed in different points of the neck of femur in the treatment of intertrochanteric fracture of femur. Method Three pairs of fresh femora of adults aging from 55 to 65 are taken. They are made into AO type A1.1 intertrochanteric fracture. Fracture specimens are fixed by PFN. The mechanical testing machine loads the fracture model at a speed of 0.5mm/s. The stress distribution of the fracture broken ends, the opening angle of the fracture broken ends, and the relationship between load and displacement are recorded respectively. Result The stress change of the group inferior of the small trochanter is smaller than that of the group superior. The opening angle of the fracture of the group inferior is smaller than that of the group superior. The displacement of the top of the femoral head of the group inferior is smaller than that of the group superior. Conclusion The performance of the group inferior is better than that of the group superior. Thus it can be concluded that when two lag screws of PFN were placed in the middle and below 1/3 part of femoral neck, the biomechanical properties are better, the structure is relatively more stable, and the stress bearing is more reasonable.

Abstract: Numerical simulation of flow field and flow noise was carried out on SUBOFF with Lighthill acoustical analogy and large eddy simulation method. The results agreed well with the numerical and experimental results obtained from published literature. The validation of the computational method of flow noise used in this paper was carried out. The geometric model was established for the unmanned underwater vehicle with full appendages and the flow field’s computational region discretization was carried out by using structural grid. Numerical simulation of flow noise for unmanned underwater vehicle with full appendages was taken. The numerical results show that the angle of attack has little effect on the flow noise level of the vehicle while the angle ranged from 0° to 4°. Compared with the “＋”-type rudders, the flow noise level of the underwater vehicle with “X”-type rudders is about 3dB lower.

Abstract: Based on the Finite Element theory, Nastran analysis software is used to calculate a motor tricycle frame for static and dynamic simulation. From the calculation, the article analyzed the strength, deformation and fatigue degree of the agricultural tricycle frame. The stress distribution cloud picture is obtained with the weak link found and the general level of the structure strength assessed, thereby providing the data of valuable structure analysis for the optimization and reliability design. All of above results can provide theoretical guidance for the design of motor tricycle frame.

Abstract: It is very important to develop the technology of the hypersonic vehicle along with the demand of many countries. This article summarizes the technology of MHD flow control and MHD generator and analyzes key technical issues of application of MHD. It included increase theoretic research and found accurate 3D model of MHD flow. The first, it needs to develop technology of large dimension plasma generator to impose effect of MHD in scramjet, at the same time it also needs to consider weight volume material and thermal protective; The second, it needs to build model of MHD energy bypass and calculate range of application of MHD.

Abstract: Force distributions on coils have been simulated with vector magnetic analysis. Resonance of 3-axis optical head actuator has been obtained for 50.5Hz, 54.8Hz and 205.2Hz in focus, track and tilt directions respectively with ANSYS modal solution. Resonance frequency is mainly determined by suspension wires, and Wire-angle, length, radius and sections are main wires’ parameters. The effects of suspension wires’ parameters on resonance response has been gotten and discussed.

Abstract: It proposed the finite element analysis to the derrick of workover rig in the paper. The stress distributing rule of derrick has been found, based on the finite element analysis of established derrick model. It analyzed the reasons for the effects of derrick thigh stress due to the derrick sustentation disposal format, the function of doorframe structure and the producing of dangerous section. The optimal derrick structure has been made up after calculating the derrick working stress, stress state and displacement measure.

Abstract: Design and fabrication of a tactical motor nozzle flexible joint were accomplished in this paper. The miniature flexible joint configuration characteristics were analyzed. The silicone rubber was selected as the elastomer ring material based on the mechanical properties test. Individual reinforcement and elastomer rings were assembled to form the flexible joint by transfer molding. Test results indicate that the flexible joint meet the performance requirements.