Accurate calculation results of roll temperature are the key factors in rolling cooling and lubricating technology during the single-stand reversing cold rolling process. By combining the high-strength steel rolling e...Accurate calculation results of roll temperature are the key factors in rolling cooling and lubricating technology during the single-stand reversing cold rolling process. By combining the high-strength steel rolling experiments ,the numerical simulation of roll temperature, and the influence factors in reversing cold rolling were studied. The research results correspond with those of rolling experiments and show that the research method could provide effective instruction for roll cooling and emulsion flow rate control during the on-site rolling process.展开更多
针对现有的研究大多集中在大型浮式液化天然气生产储卸装置(Floating Liquefied Natural Gas System,FLNG)船的运动性能,忽略其液舱超低温对结构强度的影响,参考实际工程船型与在位工况,使用有限元软件搭建液舱的热力耦合模型,采用顺序...针对现有的研究大多集中在大型浮式液化天然气生产储卸装置(Floating Liquefied Natural Gas System,FLNG)船的运动性能,忽略其液舱超低温对结构强度的影响,参考实际工程船型与在位工况,使用有限元软件搭建液舱的热力耦合模型,采用顺序热力耦合方法分析液舱的温度和应力分布。结合挪威船级社(DNV)的相关规定,进一步对液舱的结构强度进行校核。结果显示:超低温温度场会影响液舱的应力分布;考虑超低温及外载荷影响的应力结果满足DNV规范要求。展开更多
针对山区航道中布设虚拟航标基站缺乏指导方法的问题,从基站AIS信号覆盖的角度推导基站布设间距模型。首先,通过实地实验采集山区航道AIS信号场强,发现Egli模型总体上高估了山区航道中AIS信号衰减的速度,山体遮挡会造成AIS信号场强快速...针对山区航道中布设虚拟航标基站缺乏指导方法的问题,从基站AIS信号覆盖的角度推导基站布设间距模型。首先,通过实地实验采集山区航道AIS信号场强,发现Egli模型总体上高估了山区航道中AIS信号衰减的速度,山体遮挡会造成AIS信号场强快速下降。然后,基于实验数据,采用曲线拟合误差的方法修正Egli模型的参数,得到适合于山区航道的AIS信号场强评估的修订模型。修订模型对AIS信号场强的评估精度提高到94%以上,较Egli模型提高了55%以上。最后,基于修订模型,以-107 d B·m作为基站信号覆盖范围边界,推导山区航道的虚拟航标基站布设间距模型。该模型能保证船舶接收到基站信号的可靠性高于80%。展开更多
文摘Accurate calculation results of roll temperature are the key factors in rolling cooling and lubricating technology during the single-stand reversing cold rolling process. By combining the high-strength steel rolling experiments ,the numerical simulation of roll temperature, and the influence factors in reversing cold rolling were studied. The research results correspond with those of rolling experiments and show that the research method could provide effective instruction for roll cooling and emulsion flow rate control during the on-site rolling process.
文摘针对现有的研究大多集中在大型浮式液化天然气生产储卸装置(Floating Liquefied Natural Gas System,FLNG)船的运动性能,忽略其液舱超低温对结构强度的影响,参考实际工程船型与在位工况,使用有限元软件搭建液舱的热力耦合模型,采用顺序热力耦合方法分析液舱的温度和应力分布。结合挪威船级社(DNV)的相关规定,进一步对液舱的结构强度进行校核。结果显示:超低温温度场会影响液舱的应力分布;考虑超低温及外载荷影响的应力结果满足DNV规范要求。
文摘针对山区航道中布设虚拟航标基站缺乏指导方法的问题,从基站AIS信号覆盖的角度推导基站布设间距模型。首先,通过实地实验采集山区航道AIS信号场强,发现Egli模型总体上高估了山区航道中AIS信号衰减的速度,山体遮挡会造成AIS信号场强快速下降。然后,基于实验数据,采用曲线拟合误差的方法修正Egli模型的参数,得到适合于山区航道的AIS信号场强评估的修订模型。修订模型对AIS信号场强的评估精度提高到94%以上,较Egli模型提高了55%以上。最后,基于修订模型,以-107 d B·m作为基站信号覆盖范围边界,推导山区航道的虚拟航标基站布设间距模型。该模型能保证船舶接收到基站信号的可靠性高于80%。
