热声联合作用下金属薄壁结构动态响应分析

未来飞行器在服役过程中会遇到气动热、力、振动、噪声等多种载荷联合作用的严酷环境,其结构设计、分析与试验验证面临巨大的技术挑战.针对受热结构在随机噪声载荷作用下的动态响应问题,采用基于顺序耦合策略的谱分析法分析热声耦合动态响应.通过对典型结构的仿真分析,给出了响应均方根应变和功率谱密度响应等计算结果,并与试验结果从数值和形态上进行了比较.结果表明,结构受热后各阶局部模态频率降低明显,功率谱密度响应曲线峰值对应的频率发生明显的前移,随机噪声载荷引起的响应均方根应变很小,并且仅能激起结构的局部模态,分析与试验结果在趋势与数值上均吻合较好,具有较好的工程实用性.

Dynamic Response Analysis of Metallic Thin-walled Structures under Thermo-acoustic Combined Loading

Combined loading environment including aerodynamic heat ,static load,vibration and acoustic load will occur when a future aircraft is in service ,which brings a great challenge for the design ,analysis and test validation .In order to deal with the dynamic response of heated structures under random acoustic loadings,a spectral analysis method based on the sequential coupling tactic is employed to solve the ther-mo-acoustic coupling problem .Through the analysis of typical structures , root mean square value of strains and power spectral density response are presented to make comparison with test results .Results re-veal that frequencies of local modal reduce evidently when the structure is heated ,and frequencies corre-sponding to the peak value of power spectral density curves move forward obviously .Moreover,only local modals can be triggered by random acoustic loadings ,and root mean square value of strain arisen by ran-dom acoustic loadings is negligible .Analysis results match well with test results ,which means the capabil-ity in engineering practice.