Numerical model for a commercial aircraft water landing
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摘要: 近海/跨海使用的飞机必须考核水上迫降性能,而目前飞机抗坠毁标准、设计方法和分析方法通常只考虑硬着陆情况,很少考虑水面迫降情况,这是由于水上迫降涉及多场耦合,问题十分复杂.为了简化问题,采用了解耦的方法,将仿真与试验相结合,利用MSC.PATRAN/DYTRAN软件平台,建立全机有限元模型,包括全尺寸机身、机翼和尾翼结构,并导入具体参数,对13种工况条件进行了动力学数值仿真计算.预测了飞机撞击水面过程中结构的瞬态应力分布,对飞机机身下部蒙皮进行了强度分析,表明飞机在着水过程中蒙皮不会发生损坏.Abstract: Aircraft water impact crashworthiness must be considered for the aircraft used near or over the sea. The current crashworthiness criteria, design approaches and analysis methods have mainly focused on the ground impact conditions, without adequately accounting for fundamental differences associated with water crashes. This is because the crash dynamics in water impact condition is extremely complex with multi-physics interacting. To simplify the problem, an uncoupled method is proposed, using finite element simulation combined with corresponding experiments. A finite element model of reasonably simplified aircraft structure including the fuselage, wing and empennage is established by using MSC.PATRAN/MSC.DYTRAN code. The loading condition is transformed from the ditching test and thirteen dynamic load cases are considered in computation. Corresponding stress distributions for each case are predicted. It is shown that the strength of the skin on the bottom of fuselage will not be failed.
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Key words:
- water landing /
- finite element method /
- aircraft /
- dynamics /
- strengthening /
- crashworthiness
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