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采用CFD方法对船体从船台上纵向重力式下水这一运动过程进行动态数值模拟.以RANS方程和标准湍流模型作为控制方程,并采用VOF方程处理自由液面,通过求解得到船体所受到的水动力.考虑船体下水时可能发生的横向运动,建立了完整的三维运动方程.通过数值计算,考察船台和船体的各个状态参数(两岸形状,船体重心位置,船体重量,船台倾角,船台摩擦系数,船体下水初始位置等)对船体下水运动的影响.根据预报的结果,绘制出船体下水运动参数(加速度,速度,滑程等)与状态参数的关系曲线,并对其进行分析,得到一些有意义的结论,以期能够用于指导实船下水工艺. 相似文献
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Indoor air pollutants impact human health, comfort and productivity. The method of photocatalysis has been applied mainly
in flow reactors and little information is available on indoor air pollutant removal in airtight reactors. In the paper, experiments
were carried out to remove formaldehyde (HCHO), ammonia (NH3) and volatile organic compounds (VOCs) in the airtight and ventilated chambers. Results demonstrated that 90.4% of HCHO,
92.3% of NH3 and 57.9% of VOCs were removed in the amine adsorption process, while 67.5% (hereinbefore, these are the mass fraction) of
HCHO, 60.0% of NH3, and 61.2% of VOCs were removed in the photocatalytic process. However, ozone-assisted photocatalytic process showed great
potential to degrade indoor air pollutants in the ventilated chamber. Factors and mechanisms of the photocatalytic degradation
of HCHO, NH3 and VOCs were also discussed. 相似文献
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主要以锈蚀程度、预加荷载、保护层厚度、钢筋类型(光圆钢筋和变形钢筋)以及龄期为变量,通过一系列试验,研究分析了锈蚀和荷载对钢筋粘结强度的影响。 相似文献
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