相场法模拟悬浮熔融硅液滴内部对流及自由界面变形现象

为了模拟具有高密度比的两相流,提出采用牛顿迭代求解半隐式格式离散Cahn-Hilliard方程的方法,应用相场法模拟水的溃坝流和水下气泡的上升变形过程,发现水碰到右边壁面时,水面上卷,气泡在浮力作用下逐渐上升,从球形逐渐变为帽形,模拟结果与界面跟踪法模拟结果一致,验证了数值算法的正确性.在此基础上,数值模拟了悬浮熔融硅液滴的流动、变形过程,结果表明,具有初始变形的液滴在表面张力的作用下逐渐收缩,液滴内产生对流,然后,液滴逐渐变为长条状,液滴内分布着4个涡胞,沿纵向排列.     

Evaluation on contribution of steel products to environmental improvement from life cycle assessment perspectives

High functionality given to steel products results in incremental environment loads at the steelmaking stage. However, at the stage of utilization, high-functional steel products prove more environment friendly than their conventional counterparts in many cases. Therefore, evaluation on contribution of steel products to environmental improvement requires an integrated approach that considers the product over its entire life cycle — life cycle assessment (LCA). This paper discusses the relationship between the improvement of steel products performance and environmental impact from the entire life cycle perspectives. The LCA method to calculate and assess contribution of high-functional steel products during the life cycle to environmental improvement is explained. Two case studies of Baoshan Iron &; Steel Co., Ltd. (Baosteel for short) are given to show that LCA is a scientific and systematic method for eco-materials evaluation or eco-design: ? in a power transformer, using silicon steel B30P110 to replace B30G130 can reduce carbon dioxide emissions in the region of 15.1% over the life cycle of the power transformer; ? tinplate steel of Baosteel for two-piece steel cans experienced six times thickness reduction from 0.280 to 0.225mm, which results in 14.5% emission reduction over the life cycle of two-piece steel cans. It is a systematic and scientific method for evaluating on products environmental performance from life cycle perspective.     

硅粉混凝土的路用性能

对硅粉高强混凝土的强度、耐磨性、疲劳性等路用性能进行一系列试验研究,结果表明,在路面混凝土中掺加适当的硅粉能显著提高混凝土的路用性能。     

硅粉对混凝土路用性能的影响

研究了硅粉高强混凝土的强度、耐磨性和疲劳性等路用性能,充分论述了硅粉对混凝土路用性能的影响。试验结果表明,在路面混凝土中掺加适当的硅粉能显著提高混凝土的路用性能。最后,对硅粉混凝土的施工工艺进行了研究。     

有机发光器件的研究及应用前景

介绍了有机发光器件(OLED)的研究历程、结构、发光机理和研究的热点。展示了最近的产业化成果,并预测OLED的应用前景。     

船舶外场涂装局部集气罩设计

以捕集船舶外场涂装作业过程产生的挥发性有机物(Volatile Organic Compounds, VOCs)气体为出发点,采用理论研究、仿真模拟和现场试验的方法,形成船舶外场涂装局部集气罩设计方案,并设定合理的验证方法检验方案的可行性和收集率。结果表明,船舶外场涂装局部集气罩可有效捕集VOCs气体,从源头控制污染物扩散,降低污染。     

静水压力作用下夹芯板结构的变形规律分析

  目的  在轴向承载时,低模高弹体存在侧向形变大、均匀性差等问题,常规电阻式应变测试方法难以准确获取材料的泊松比。为了消除试件侧向变形的不均匀性影响,准确获取高分子材料的泊松比值,  方法  基于弹性力学理论,推导了圆柱形低模高弹体在侧向刚性约束时的压缩模量、弹性模量与泊松比的表达式,建立了试验的理论模型。在理论分析的基础上,提出了由钢制套筒侧向约束轴向加载的泊松比测试方案,并开展了天然橡胶及HW-050型浮力材料的钢制套筒约束试验研究,验证了该试验测试方法的有效性及合理性。最后利用ABAQUS软件对浮力材料模型试验过程进行仿真,分析不同钢筒壁厚对试验的影响规律。  结果  研究结果表明,该试验测试方法可被用于准确测量低模高弹体材料的泊松比值,适用于低模量、高弹特性材料的力学性能研究。  结论  研究工作可为相关试验测试提供参考。     

Modelling the silica pump in the Permanently Open Ocean Zone of the Southern Ocean

A coupled 1D physical–biogeochemical model has been built to simulate the cycles of silicon and of nitrogen in the Indian sector of the Permanently Open Ocean Zone of the Southern Ocean. Based on a simplified trophic network, that includes two size classes of phytoplankton and of zooplankton, and a microbial loop, it has been calibrated by reference to surface physical, chemical and biological data sets collected at the KERFIX time-series station (50°40′S–68°25′E). The model correctly reproduces the high nutrient low chlorophyll features typical of the studied area. In a region where the spring–summer mixed layer depth is usually deeper than 60 m, the maximum of chlorophyll never exceeds 1.5 mg m⁻³, and the annual primary production is only 68 g C m⁻² year⁻¹. In the surface layer nitrate is never exhausted (range 27–23.5 mmoles m⁻³) while silicic acid shows strong seasonal variations (range 5–20 mmoles m⁻³). On an annual basis 71% of the primary production sustained by nanophytoplankton is grazed by microzooplankton. Compared to North Atlantic, siliceous microphytoplankton is mainly prevented from blooming because of an unfavourable spring–summer light-mixing regime. Silicic acid limitation (high half saturation constant for Si uptake: 8 mmoles m⁻³) also plays a major role on diatom growth. Mesozooplankton grazing pressure excerpts its influence especially in late spring. The model illustrates the efficiency of the silica pump in the Southern Ocean: up to 63% of the biogenic silica that has been synthetized in the photic layer is exported towards the deep ocean, while only 11% of the particulate organic nitrogen escapes recycling in the surface layer.     

基于碳化硅材料柴油机颗粒过滤器开发与试验

阐述了碳化硅为原材料的柴油机颗粒过滤器生产工艺,并对载体的微观结构进行SEM分析和用压汞仪测试,结果表明重结晶碳化硅过滤器微孔分布均匀一致;对载体进行适应性涂敷试验,SEM分析结果表明:含有催化剂浆料可以均匀地涂敷在碳化硅晶粒上;载体对PM的过滤效率进行了发动机台架测试,过滤效率高达99%。     

考虑硅钢片各向异性的永磁同步电机三维电磁场计算

本文利用ANSOFT数值计算软件的MAXWELL 3D模块建立了某永磁电机的有限元模型,模拟了取向硅钢片的各向异性特性,通过进行三维电磁场分析计算了电机的主要参数,提高了仿真计算的精度。