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为研究乘员舱内不同气流组织下的人体热舒适性,找出进气参数对人体热舒适性影响的规律,将Fluent计算得到的9种进气方案的流场结果作为环境参数导入TAITherm中进行热舒适性分析。同时引入面部平均空气龄和能量利用率两项指标对乘员舱气流组织进行更全面的评价。结果表明进气总量对3位乘员热舒适性和平均面部空气龄影响程度最大,1号口进气温度对能量利用率的影响程度最大。综合考虑3位乘员的热舒适性、面部平均空气龄和能量利用率3项评价指标,发现当进气总量为1 800 kg/h, 1、2号口进气温度都为22℃,1、2号口进气量比值为6∶4时3项指标均表现良好,为最优的进气参数组合。 相似文献
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为明确高速列车铸钢制动盘与锻钢制动盘材料的组织转变特性,采用DIL 805L型热膨胀仪测定高速列车用铸钢制动盘与锻钢制动盘用低合金钢材料的过冷奥氏体连续冷却转变特性并绘制CCT曲线,分析并测试2种制动盘材料在不同冷却速率条件下的微观组织结构及显微硬度。研究结果表明:铸钢制动盘低合金钢的奥氏体转变(AC3)温度为847℃,锻钢制动盘低合金钢的AC3温度为862℃,在0.2℃/s的缓慢冷却条件下,锻钢制动盘材料会发生奥氏体向铁素体-珠光体组织的转变,铸钢制动盘材料在冷却速率大于20.0℃/s的条件下可以获得完全的马氏体组织,而锻钢制动盘材料的完全马氏体组织转变临界冷却速率为50.0℃/s。在制动盘实际服役过程中,摩擦面上的局部过热区会在冷却过程中发生贝氏体和马氏体转变并产生局部硬化。 相似文献
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结合战时装备保障实际情况和战损装备抢修任务特点,分析了现有战损装备抢修任务指派模型的特点及不足.依据紧急程度对战损装备抢修任务进行分类,建立了不同紧急度对应的装备抢修任务指派模型,重点是利用蚁群算法对模型进行求解.最后通过某装备保障想定的实例进行了验证,结果表明该算法操作简单、切实有效,能有效实施战损装备应急抢修任务的指派,在装备保障智能决策系统中有较好的应用前景. 相似文献
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Semi-quantitative study on the Staebler--Wronski effect of hydrogenated amorphous silicon films prepared with HW-ECR-CVD system 总被引:1,自引:0,他引:1
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The method of numerical simulation is used to fit the relationship between
the photoconductivity in films and the illumination time. The generation and
process rule of kinds of different charged defect states during illumination
are revealed. It is found surprisingly that the initial photoconductivity
determines directly the total account of photoconductivity degradation of
sample. 相似文献
5.
Optical properties of hexagonal boron nitride thin films deposited by radio frequency bias magnetron sputtering
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The optical properties of hexagonal boron nitride (h-BN) thin films
were studied in this paper. The films were characterized by Fourier
transform infrared spectroscopy, UV--visible transmittance and
reflection spectra. h-BN thin films with a wide optical band gap Eg (5.86 eV for the as-deposited film and 5.97 eV for the
annealed film) approaching h-BN single crystal were successfully
prepared by radio frequency (RF) bias magnetron sputtering and
post-deposition annealing at 970~K. The optical absorption behaviour
of h-BN films accords with the typical optical absorption
characteristics of amorphous materials when fitting is made by the
Urbach tail model. The annealed film shows satisfactory structure
stability. However, high temperature still has a significant
effect on the optical absorption properties, refractive index n,
and optical conductivity σ of h-BN thin films. The
blue-shift of the optical absorption edge and the increase of Eg probably result from stress relaxation in the film under high temperatures. In addition, it is found that the refractive index
clearly exhibits different trends in the visible and ultraviolet regions.
Previous calculational results of optical conductivity of h-BN
films are confirmed in our experimental results. 相似文献
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