关键词: 随机能量流分析, 统计能量分析, 随机激励, 能量密度, 框架结构

Abstract: The formulations of random energy flow analysis (REFA) for beam structures were derived, which applies to the loading situation of random excitation. The theoretical relationship between REFA and statistical energy analysis (SEA) was investigated for beam structures, and it is found that the energy flow characteristic reflected by REFA for bending wave field is similar to that exhibited by two coupling oscillators in conventional SEA. REFA was applied to a 3D frame structure consisting of 3 identical beams, where the effects of concentrated random force being exerted at different positions on the same wave component were mainly investigated. The results show that the driving position of the force can significantly affect the global energy response and power flow in the structure, while has little effect on the total energies of wave fields directly subjected to excitations. SEA was utilized to perform vibration analysis for the structure as well. The solutions from SEA and REFA indicate that, only for the subsystems directly excited, total energy responses evaluated by the two methods are in good agreement.