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海战场综合电子信息系统仿真测试技术 总被引:1,自引:0,他引:1
为了对海战场综合电子信息系统的功能和性能指标进行测试,迫切需要对海战场综合电子信息系统的测试内容、测试方法、测试环境构成、态势驱动方式等内容进行深入研究.文章介绍了海战场综合电子信息系统的组成、功能和评估指标体系,详细阐述了海战场综合电子信息系统仿真测试系统的类型、功能、成员设计、测试过程、主要模型及关键技术.该仿真测试系统已经用于某作战指挥系统和某指挥自动化系统应用软件的研究测试中,可以为海战场综合电子信息系统的研制提供全面的仿真测试环境. 相似文献
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In this study, a drilling experiment was conducted on titanium ASTM B265 Grade 2 material using PVD coated carbide inserts. Two types of coolants (Wet and LN2) were used. The variables in the experiment were feed rate (f) and cutting speed (Vc). The depth of the drilling was constant. Cutting temperature (T), thrust force (Ft), surface roughness (Ra), and the hole quality (circularity, cylindricity, and perpendicularity) were analyzed. The tool wear and chip morphology were studied. The result of the experiment indicates that there is 6–59% reduction in cutting temperature when LN2 is used, high thrust force values were recorded for LN2 coolant condition, surface roughness (Ra) values were higher for LN2 coolants. Hole quality is not favorable in LN2 coolant supply. 相似文献
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《Materials Science & Technology》2013,29(4):418-423
AbstractBy taking the method of liquid–metal cooled directional solidification, alloys with a nominal composition of Nb–14Si–24Ti–10Cr–2Al–2Hf (at-%) were prepared under different conditions. Alloys were initially directional solidified with different withdrawal rates (R?=?1·2, 6, 18 mm min?1) at 1750°C and subsequently heat treated at 1450°C for 10 h. These processes aimed to investigate the microstructure of directionally solidified (DS) and heat treated (HT) alloys by XRD, SEM, and EDS. The microstructure of DS alloy was composed of (Nb,Ti)SS, (Nb,Ti)5Si3, and Laves phase Cr2Nb, and the former two components formed (Nb,Ti)SS+(Nb,Ti)5Si3 eutectics. In addition, (Nb,Ti)5Si3 laths only presented in DS1·2 alloy. With the increasing withdrawal rates, the microstructure of alloy altered from hypereutectic into pseudo-eutectic, accompanied with the eutectic morphology transformation from petaloid into coupled. Also, the dimension of constituent phases reduced. However, after heat treatment, the constituent phases did not change. The petaloid morphology of eutectics in DS specimens disappeared and coupled eutectic transferred into network. The block or needle-like Cr2Nb gathered along the boundary between (Nb,Ti)5Si3 and (Nb,Ti)SS, and the overall alloy composition became homogenisation. 相似文献
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介绍了在地面安放振击器,进行振击解除卡钻事故的方法,以及振击器的结构、使用方法,并通过试验证明振击是一种有效的解卡方法。 相似文献
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WANG Zhi-ming GUO Xiao-le LI Ming HONG Yu-kui College of Oil Gas Engineering China University of Petroleum Beijing China 《水动力学研究与进展(B辑)》2009,21(3):366-372
Wellbore cleaning is a key technology for the Extended Reach Drilling (ERD). The success of drilling extended reach wells depends directly upon the quality of wellbore cleaning. The rotation of the drillpipe, and hydraulic and rheological parameters, are the key factors for wellbore cleaning. In this study, Computational Fluid Dynamics (CFD) is applied to simulate solid-liquid two-phase flows in wellbore annulus. The annual flow field with the presence of drillpipe rotation is described through analyzing various rotation conditions. The results indicate that the quasi-spiral flow is the main flow pattern for liquid-solid transport in the horizontal annulus. The influence of rotation on the cuttings transport is also investigated, as the rotation of drillpipe increases the disturbance of liquid to solid in annulus. As a result, the solid flow becomes favorable and the solid volume is reduced. Comparisons with previously published results are also performed to prove the importance of drillpipe rotation in the wellbore clearing for the ERD. 相似文献