发动机吊架中风车不平衡振动传递特性研究
发布时间：2019-01-26 16:27
【摘要】：风车不平衡振动具备复杂多变且振动幅值大的特点,主要由叶片丧失、轴支承失效引起。发动机产生的不平衡振动经吊架、机翼传递到客舱及驾驶舱,影响乘客乘坐的舒适性及飞行员安全操控飞机的水平。现行民用航空适航规章要求,当持续振动危及飞机的安全时,要有停止发动机转动的措施。然而,随着发动机风扇叶片的增大,风扇转子在发动机停车后将承受巨大的气动作用力,发动机因叶片丧失而停车后非对称风扇转子叶片将在空气动力作用下继续转动,从而产生严重的不平衡振动载荷。本文以某型民用飞机为研究对象,发动机采用吊架结构安装在机翼上,分析了发动机风车不平衡工况下吊架的振动响应,然后对影响吊架振动及振动传递特性的因素进行了研究。本文主要进行了以下几方面的研究:首先对发动机吊架振动原因及振动机理进行研究,接着对吊架振动传递理论及研究方法进行具体分析;分析发动机吊架构成及安装形式,利用MSC.PatranNastran有限元软件建立盒式梁结构的吊架模型;分析振源位置不同及吊架阻尼系数不同时,计算并比较吊架振动响应和振动传递路径的区别,得出吊架本身的振动特性;确定风车不平衡振动载荷谱,计算并比较发动机风车不平衡工况时吊架的振动响应及振动传递路径。最后考虑了发动机风车不平衡工况时,转子加减速对吊架振动特性的影响。
[Abstract]:The unbalanced vibration of windmill is characterized by complex and variable vibration amplitude, which is mainly caused by the loss of blade and the failure of shaft support. The unbalanced vibration generated by the engine is transmitted to the cabin and cockpit by the hangers, which affects the comfort of the passengers and the level of the pilots safely operating the aircraft. The current civil aviation airworthiness regulations require that when the continuous vibration endangers the safety of the aircraft, there must be measures to stop the engine from turning. However, with the increase of engine fan blade, the fan rotor will bear a huge aerodynamic force after engine shutdown, and the asymmetric fan rotor blade will continue to rotate under the aerodynamic action after the engine stops due to the loss of the blade. As a result, a severe unbalanced vibration load is generated. In this paper, a certain civil aircraft is used as the research object, and the engine is mounted on the wing with a hanger structure. The vibration response of the hanger under the unbalanced condition of the engine windmill is analyzed. Then, the factors affecting the vibration and vibration transfer characteristics of the hanger are studied. This paper mainly studies the following aspects: firstly, the vibration causes and vibration mechanism of the engine hanger are studied, and then the theory and research method of the vibration transfer of the hanger are analyzed concretely; The structure and installation form of engine hanger are analyzed, and the hanger model of boxed beam structure is established by using MSC.PatranNastran finite element software. The difference of vibration response and vibration transfer path is calculated and compared by analyzing the difference of vibration source location and damping coefficient of suspension frame, and the vibration characteristics of the suspension frame itself are obtained by comparing and calculating the difference between the vibration response and vibration transfer path of the hanger. The load spectrum of unbalance vibration of windmill is determined and the vibration response and vibration transfer path of suspension are calculated and compared under the unbalanced working condition of engine windmill. Finally, the effect of rotor acceleration and deceleration on the vibration characteristics of the suspension is considered when the engine windmill is unbalanced.
【学位授予单位】：中国民航大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：V231.92
本文编号：2415665
[Abstract]:The unbalanced vibration of windmill is characterized by complex and variable vibration amplitude, which is mainly caused by the loss of blade and the failure of shaft support. The unbalanced vibration generated by the engine is transmitted to the cabin and cockpit by the hangers, which affects the comfort of the passengers and the level of the pilots safely operating the aircraft. The current civil aviation airworthiness regulations require that when the continuous vibration endangers the safety of the aircraft, there must be measures to stop the engine from turning. However, with the increase of engine fan blade, the fan rotor will bear a huge aerodynamic force after engine shutdown, and the asymmetric fan rotor blade will continue to rotate under the aerodynamic action after the engine stops due to the loss of the blade. As a result, a severe unbalanced vibration load is generated. In this paper, a certain civil aircraft is used as the research object, and the engine is mounted on the wing with a hanger structure. The vibration response of the hanger under the unbalanced condition of the engine windmill is analyzed. Then, the factors affecting the vibration and vibration transfer characteristics of the hanger are studied. This paper mainly studies the following aspects: firstly, the vibration causes and vibration mechanism of the engine hanger are studied, and then the theory and research method of the vibration transfer of the hanger are analyzed concretely; The structure and installation form of engine hanger are analyzed, and the hanger model of boxed beam structure is established by using MSC.PatranNastran finite element software. The difference of vibration response and vibration transfer path is calculated and compared by analyzing the difference of vibration source location and damping coefficient of suspension frame, and the vibration characteristics of the suspension frame itself are obtained by comparing and calculating the difference between the vibration response and vibration transfer path of the hanger. The load spectrum of unbalance vibration of windmill is determined and the vibration response and vibration transfer path of suspension are calculated and compared under the unbalanced working condition of engine windmill. Finally, the effect of rotor acceleration and deceleration on the vibration characteristics of the suspension is considered when the engine windmill is unbalanced.
【学位授予单位】：中国民航大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：V231.92
【引证文献】
相关期刊论文 前1条
1 白杰;冯诚;;基于有限元功率流法的飞机吊挂传递路径分析[J];航空计算技术;2018年01期
，本文编号：2415665
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