To achieve efficient and refined thermal environment simulations for single-phase and two-phase flows in aircraft cabins,we propose an integrated analysis method.This approach enables rapid coupled heat transfer calcu...To achieve efficient and refined thermal environment simulations for single-phase and two-phase flows in aircraft cabins,we propose an integrated analysis method.This approach enables rapid coupled heat transfer calculations among single-phase flow,two-phase flow,and solids within a single time step.For single-phase fluid and solid equipment,a fast numerical algorithm for natural convection is developed using a loosely coupled strategy,dividing the single-phase flow into developmental stages for efficient temperature field computation.For two-phase flow and the fuel tank wall,a transient heat transfer model is constructed at the gas-liquid-solid boundary,facilitating fast thermal analysis.These methods are unified for integrated simulation of the cabin’s thermal environment.Validation based on two-dimensional models demonstrates a speedup by a factor of 7.9,while maintaining an average temperature error of less than 1%at two-phase nodes.The method’s robustness is confirmed under various high-temperature boundary conditions.展开更多
在航空器坠撞冲击下,腰椎损伤是影响航空乘员(简称乘员)生存能力的关键因素。本文旨在研究乘员在垂向冲击载荷下的人体腰椎损伤情况。首先,利用高精度数值假人THUMS(total human model for safety)研究了冲击载荷加速度的加载峰值和加...在航空器坠撞冲击下,腰椎损伤是影响航空乘员(简称乘员)生存能力的关键因素。本文旨在研究乘员在垂向冲击载荷下的人体腰椎损伤情况。首先,利用高精度数值假人THUMS(total human model for safety)研究了冲击载荷加速度的加载峰值和加载时间对乘员腰椎生物力学损伤的影响;其次,分析了THUMS和HybridⅢ假人在垂向冲击工况下腰椎动态响应的差异;最后,从细观角度研究了乘员腰椎的生物力学损伤。研究表明,速度变化量不变时,随着加速度的加载峰值增大,乘员腰椎轴向载荷峰值增幅较大,腰椎弯矩峰值增幅较小。乘员腰椎轴向载荷峰值与能量积累的速度正相关;加载时间过短时,惯性效应限制腰椎屈曲,导致腰椎弯矩较小。L5截面处腰椎轴向载荷最大,L1截面处腰椎弯矩最大,乘员腰椎损伤评估要综合考虑轴向压缩力和弯矩的影响。从生物力学上看,腰椎的皮质骨和关键韧带的损伤风险最大。展开更多
为保证民机航空安全,满足民机抗爆结构设计要求,通过考虑藏匿爆炸物载体尺寸、爆炸物当量等重要因素,提出了民用飞机抗爆结构设计通用技术要求,基于商用有限元软件建立了抗爆结构仿真分析方案。抗爆结构主材料选用钛合金,爆炸物当量为10...为保证民机航空安全,满足民机抗爆结构设计要求,通过考虑藏匿爆炸物载体尺寸、爆炸物当量等重要因素,提出了民用飞机抗爆结构设计通用技术要求,基于商用有限元软件建立了抗爆结构仿真分析方案。抗爆结构主材料选用钛合金,爆炸物当量为100 g TNT(三硝基甲苯),通过数值仿真的手段,分析了不同炸药位置对抗爆罐体的影响,以验证所设计的罐体在100 g TNT当量爆炸载荷作用下罐体结构的完整性。同时,为达到定向破坏定向释放爆炸能量且机体结构损伤范围可控的目的,验证了所设计的抗爆结构冲击端头剪断剪切销并顺利飞出罐体的可靠性,为民机定向爆破装置设计提供参考。展开更多
文摘To achieve efficient and refined thermal environment simulations for single-phase and two-phase flows in aircraft cabins,we propose an integrated analysis method.This approach enables rapid coupled heat transfer calculations among single-phase flow,two-phase flow,and solids within a single time step.For single-phase fluid and solid equipment,a fast numerical algorithm for natural convection is developed using a loosely coupled strategy,dividing the single-phase flow into developmental stages for efficient temperature field computation.For two-phase flow and the fuel tank wall,a transient heat transfer model is constructed at the gas-liquid-solid boundary,facilitating fast thermal analysis.These methods are unified for integrated simulation of the cabin’s thermal environment.Validation based on two-dimensional models demonstrates a speedup by a factor of 7.9,while maintaining an average temperature error of less than 1%at two-phase nodes.The method’s robustness is confirmed under various high-temperature boundary conditions.
文摘在航空器坠撞冲击下,腰椎损伤是影响航空乘员(简称乘员)生存能力的关键因素。本文旨在研究乘员在垂向冲击载荷下的人体腰椎损伤情况。首先,利用高精度数值假人THUMS(total human model for safety)研究了冲击载荷加速度的加载峰值和加载时间对乘员腰椎生物力学损伤的影响;其次,分析了THUMS和HybridⅢ假人在垂向冲击工况下腰椎动态响应的差异;最后,从细观角度研究了乘员腰椎的生物力学损伤。研究表明,速度变化量不变时,随着加速度的加载峰值增大,乘员腰椎轴向载荷峰值增幅较大,腰椎弯矩峰值增幅较小。乘员腰椎轴向载荷峰值与能量积累的速度正相关;加载时间过短时,惯性效应限制腰椎屈曲,导致腰椎弯矩较小。L5截面处腰椎轴向载荷最大,L1截面处腰椎弯矩最大,乘员腰椎损伤评估要综合考虑轴向压缩力和弯矩的影响。从生物力学上看,腰椎的皮质骨和关键韧带的损伤风险最大。
文摘为保证民机航空安全,满足民机抗爆结构设计要求,通过考虑藏匿爆炸物载体尺寸、爆炸物当量等重要因素,提出了民用飞机抗爆结构设计通用技术要求,基于商用有限元软件建立了抗爆结构仿真分析方案。抗爆结构主材料选用钛合金,爆炸物当量为100 g TNT(三硝基甲苯),通过数值仿真的手段,分析了不同炸药位置对抗爆罐体的影响,以验证所设计的罐体在100 g TNT当量爆炸载荷作用下罐体结构的完整性。同时,为达到定向破坏定向释放爆炸能量且机体结构损伤范围可控的目的,验证了所设计的抗爆结构冲击端头剪断剪切销并顺利飞出罐体的可靠性,为民机定向爆破装置设计提供参考。
