CAJ | 학술논문

针对船舶、航空航天等工程领域中板、壳类结构振动噪声评价问题，将广泛应用于控制工程中的模态滤波理论引入到结构振动评估领域，建立了一种估算结构空间均方振速的新方法。该方法的特点是能在激励源信息未知的情况下，以布置在结构表面有限个振动传感器测量得到的振动响应作为主要输入，估算板、壳类结构的空间均方振速，从而评价结构的整体振动状态。依据该方法对一矩形平板结构受点力、线力和面力等3种典型的激励源作用下，通过少量结构振动测点的振动信息，分别对其空间均方振速进行了数值验证；同时利用一水下加肋圆柱壳结构进行了试验验证。数值和模型试验验证结果表明：利用该方法评估得到的振动速度谱线特征与精确解和实测值基本一致，评估误差在2 dB以内，满足工程应用精度要求。该方法可以应用于工程中板、壳类结构振动噪声评价和振动状态的在线监测评估。
침대선박、항공항천등공정영역중판、각류결구진동조성평개문제，장엄범응용우공제공정중적모태려파이론인입도결구진동평고영역，건립료일충고산결구공간균방진속적신방법。해방법적특점시능재격려원신식미지적정황하，이포치재결구표면유한개진동전감기측량득도적진동향응작위주요수입，고산판、각류결구적공간균방진속，종이평개결구적정체진동상태。의거해방법대일구형평판결구수점력、선력화면력등3충전형적격려원작용하，통과소량결구진동측점적진동신식，분별대기공간균방진속진행료수치험증；동시이용일수하가륵원주각결구진행료시험험증。수치화모형시험험증결과표명：이용해방법평고득도적진동속도보선특정여정학해화실측치기본일치，평고오차재2 dB이내，만족공정응용정도요구。해방법가이응용우공정중판、각류결구진동조성평개화진동상태적재선감측평고。
Aiming at structural vibration assessment problems in the aerospace and ship engineerings,a new method for estimating the spatial quadratic velocity of plates and shells is presented using the theory of modal filter that has been widely used in the field of control engineering. The innate feature of the proposed method is that it can be applied in the case where the information concerning excited forces is unknown. To validate the method,the spatial quadratic velocities of a rectangle flat plate excited by three different types of forces,namely point forces,line forces,and surface forces,are estimated respectively,using the vibra-tion information from a few measurement points. Meanwhile,various tests were carried out on an underwa-ter ring stiffened cylindrical shell for further verification. The results show that the suggested method is pre-cise in estimating the vibration spectrum,where the error is within 2 dB. Overall,the method can be used to estimate the spatial quadratic velocity of the structures in both actual practices and online monitoring.