Full-scale numerical experiments were carried out on the vehicular fire in a long tunnel to study the critical ventilation velocity and back-layer distance with heat release rate of 5, 20 and 100 MW respectively. A co...Full-scale numerical experiments were carried out on the vehicular fire in a long tunnel to study the critical ventilation velocity and back-layer distance with heat release rate of 5, 20 and 100 MW respectively. A computational fluid dynamics (CFD) model of fire-driven fluid flow FDS(Fire Dynamics Simulator) was used to solve numerically a form of the Navier-Stokes equations for fire. The results were compared with the expressions proposed in the literature. A modified equation for the critical ventilation velocity was given to better fit the experimental results. A bi-exponential model that well fitted the numerical experimental results was proposed to describe the relationship between back-layer distance and ventilation velocity.展开更多
为了解决城市地下交通联系隧道(urban traffic link tunnel,UTLT)火灾烟气安全的问题,采用量纲分析方法推导出了UTLT火灾烟气回流长度的量纲一方程式;根据调查的UTLT的常见尺寸,设置了9种不同尺寸的UTLT,运用数值模拟软件FDS 5.5对这些...为了解决城市地下交通联系隧道(urban traffic link tunnel,UTLT)火灾烟气安全的问题,采用量纲分析方法推导出了UTLT火灾烟气回流长度的量纲一方程式;根据调查的UTLT的常见尺寸,设置了9种不同尺寸的UTLT,运用数值模拟软件FDS 5.5对这些隧道进行模拟计算,得到了不同工况下的火灾烟气回流长度,进而得到了UTLT火灾烟气回流长度的预测模型.通过与实验值的比较表明,该方程式和实验值吻合较好.在进一步分析的基础上,得到了UTLT的限制隧道预测模型,可为此类隧道的消防设计提供一定的技术指导.展开更多
利用AMPS程序模拟研究了非晶硅锗薄膜太阳电池的窗口层材料和厚度以及背接触势垒对电池光伏性能的影响。模拟发现带隙为1.92 e V的非晶硅碳更适合作为太阳电池的窗口层,且窗口层越薄电池的性能越好。模拟还发现,背接触势垒越低,则电池...利用AMPS程序模拟研究了非晶硅锗薄膜太阳电池的窗口层材料和厚度以及背接触势垒对电池光伏性能的影响。模拟发现带隙为1.92 e V的非晶硅碳更适合作为太阳电池的窗口层,且窗口层越薄电池的性能越好。模拟还发现,背接触势垒越低,则电池的光伏性能越好,当背接触势垒在0.11-0.51 e V的范围内时电池的转换效率不会受到背接触势垒的影响。展开更多
基金Supported by the Shanghai Municipal Infor mation Fund Project (2004)
文摘Full-scale numerical experiments were carried out on the vehicular fire in a long tunnel to study the critical ventilation velocity and back-layer distance with heat release rate of 5, 20 and 100 MW respectively. A computational fluid dynamics (CFD) model of fire-driven fluid flow FDS(Fire Dynamics Simulator) was used to solve numerically a form of the Navier-Stokes equations for fire. The results were compared with the expressions proposed in the literature. A modified equation for the critical ventilation velocity was given to better fit the experimental results. A bi-exponential model that well fitted the numerical experimental results was proposed to describe the relationship between back-layer distance and ventilation velocity.
文摘为了解决城市地下交通联系隧道(urban traffic link tunnel,UTLT)火灾烟气安全的问题,采用量纲分析方法推导出了UTLT火灾烟气回流长度的量纲一方程式;根据调查的UTLT的常见尺寸,设置了9种不同尺寸的UTLT,运用数值模拟软件FDS 5.5对这些隧道进行模拟计算,得到了不同工况下的火灾烟气回流长度,进而得到了UTLT火灾烟气回流长度的预测模型.通过与实验值的比较表明,该方程式和实验值吻合较好.在进一步分析的基础上,得到了UTLT的限制隧道预测模型,可为此类隧道的消防设计提供一定的技术指导.
文摘利用AMPS程序模拟研究了非晶硅锗薄膜太阳电池的窗口层材料和厚度以及背接触势垒对电池光伏性能的影响。模拟发现带隙为1.92 e V的非晶硅碳更适合作为太阳电池的窗口层,且窗口层越薄电池的性能越好。模拟还发现,背接触势垒越低,则电池的光伏性能越好,当背接触势垒在0.11-0.51 e V的范围内时电池的转换效率不会受到背接触势垒的影响。
