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1.
鉴于国内外密封垫片标准众多、数据量庞大,设计了基于VisualBasic与MSAccess的垫片标准查询系统,实现了垫片标准的自动化查询。扩展了部分VB控件的功能,通过捕捉鼠标事件,实现了Picturebox控件的滚轮缩放以及MSHFlexGrid控件的滚轮翻页功能。可对查询结果进行二次筛选并输出至word文档,操作便捷。 相似文献
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为研究导流螺旋片对立式循环撞击流强化撞击过程的规律,提出最优的导流螺旋片尺寸.采用Fluent软件对立式循环撞击流反应器中增加导流螺旋片前、后的撞击过程进行数值模拟,得到了导流螺旋片厚度分别为0、10、20、30mm和螺圈数分别为0、1、2的反应器流场的速度矢量图、特征撞击面上的平均速度和速度均方根差,并对比分析了其传质性能及混合性能.结果表明,增加了导流螺旋片,导流筒内部出现了流线弯曲及流动斜交,提高了流场的各向异性,使流场中速度分层明显,并增大了速度梯度,从而强化了撞击区之外的流场混合.同时,当螺圈数N=1,螺旋片的厚度L=30mm时,反应器内撞击过程中的相间传质效果最好;当不加螺旋片时,反应器内撞击过程中的相间混合效果最好. 相似文献
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Besides the macro-mechanical properties for thermal aging effect published in “Thermal aging effect on Z3CN20.09M Cast Duplex Stainless Steel” (Nuclear Engineering and Design 239(2009) 2217-2223), the thermal aging damage mechanism is investigated in this paper through nano-indentation tests and micro-structures evolution examination. Numerical simulations were carried out with GTN continuum damage model to investigate the different crack propagation process for aging. The nano-indentation hardness values increase with aging time for both phases while the hardness values of the ferrite phase are much higher and increase much more. The nano-indentation energy indicating the toughness decreases for both phases with aging time. TEM results show that the Cr-enriched α′ phase precipitates in the ferrite phase which is considered as the critical reason making the dislocation slip difficult and causing the increase of the strength and reduction of the toughness. The crack initiates from the ferrite phase instead of the austenite phase from the SEM observation and FEA simulation results, which reflects the change of the fracture mechanism for thermal aging. 相似文献
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Stainless steel clad plate is widely used in petroleum, chemical and medicine industries due to its good corrosion resistance and high strength. But cracks are often formed in clad layer during the manufacture or service, which are often repaired by repair welding. In order to ensure the structure integrity, the effects of residual stress need to be considered. The objective of this paper is to estimate the residual stress and deformation in the repair weld of a stainless steel clad plate by finite element method. The effects of heat input and welding layer number on residual stresses and deformation have been studied. The results show that large residual stresses have been generated in the repair weld. The heat input and layer number have great effects on residual stress distribution. With the heat input and welding layer number increasing, the residual stresses are decreased. Using multiple-layer welding and higher heat input can be useful to decrease the residual stress, which provides a reference for optimizing the repair welding technology of this stainless steel clad plate. 相似文献
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This paper uses finite element method (FEM) to predict the residual stress and plastic strain in the brazed joint of sealing foil-to-window frame in bonded compliant seal (BCS) design in a planar solid oxide fuel cell (PSOFC). The effects of window frame material type, sealing foil thickness, filler metal thickness and window frame thickness on residual stress and plastic strain are discussed. Large residual stress is generated in the joint, and the stress and strain are concentrated around the fillet. It is proved that the BCS design can mitigate and trap some residual stress by plastic deformation within the sealing foil. The residual stress and the ability of trapping stress of sealing foil are affected by window frame material and structure thickness. Based on the comprehensive considerations of the impact of residual stress and plastic strain, Alloy 625 as a window frame material is found to be better than Haynes 214, Hastelloy X and SUS 316L. The optimum thickness of sealing foil and filler metal BNi2 are found to be 150 μm and 75 μm, respectively. The residual stress and plastic strain are increased with the increase of window frame thickness. 相似文献
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利用有限元软件ABAQUS,开发了一个顺次耦合的角焊缝焊接热应力计算程序,研究了加氢高压换热器板式焊接密封接头应力场的分布;以此数值模拟结果为基础,结合正交试验设计方法,分析了焊接电流、电弧电压、焊接速度及预热温度4个工艺参数对焊接残余应力场的影响,找到一组使焊接残余应力最小的最优焊接工艺参数.结果表明,焊接速度对焊接残余应力的影响最大,该角焊缝焊接残余应力的最高值集中在焊缝和热影响区附近.研究结果为优化加氢高压换热器板式焊接密封的焊接工艺,预防焊接密封接头的开裂失效提供了理论基础.Abstract: Using the finite element analysis software ABAQUS, a sequentially coupled fillet welding thermal-stress program was developed to calculate the stress distribution of plate sealing joint in the high pressure hydrogenation heat exchange. Based on the numerical solutions and the orthogonal method, the influence of four welding parameters including welding current, welding voltage, welding speed and preheating temperature on residual stress distribution was analyzed and a group of optimal welding parameters were obtained, which provided a reference for preventing the failure of fillet weld sealing joint in the high pressure hydrogenation heat exchange. 相似文献
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