不等间距分舱结构声辐射特性研究

Study on characteristics of acoustic radiation from the cabin structure with nonuniform subdivision

研究舱段结构振动、声辐射特性随分舱形式改变的变化规律,对潜艇结构声学优化设计具有十分重要的意义。从结构声学设计的角度出发,在保持相邻两个舱段总长度不变的情况下,调整两个舱段的长度,采用结构有限元法、结构有限元耦合流体边界元方法,以辐射声功率、湿表面均方法向速度和辐射效率作为衡量结构噪声辐射能力的主要衡量指标,系统地研究整个结构振动和声辐射特性。在流体部分的计算中,采用网格重叠算法,以提高计算效率。通过调整分舱形式,在一定频段,改变了整个舱段结构振动声学传递函数的谱峰频率,降低了谱峰幅值,因此,可以通过改变分舱形式以改变舱段结构声学特性,使设备激振力的谱峰频率与结构振动声学传递函数的谱峰频率错开,实现对辐射噪声的控制。

S tud y on the re la tio n betw een the v ib ra tio n and aco ustic ra d ia tio n from the c a b in stru ctu re s andthe m ethod o f c a b in d iv is io n is v e ry im p o rta n t fo r the s tru c tu re -a c o u s tic o p tim iz a tio n design o f th e subm arine . From th e an gle o f th e s tru c tu re -a c o u s tic design, in th e c o n d itio n o f k e e p in g th e to ta l le n g th o f tw ocabins, a d ju s tin g the length o f the tw o ca b in s re sp e ctive ly, and the s tru c tu ra l fin ite elem e nt m ethod, andthe s tru c tu ra l fin ite elem e nt cou p le d flu id bo un da ry elem e nt m ethod are adopted fo r the n u m e ric a l c a lc u la tion , and the acoustic ra d ia tio n power, mean square norm al ve lo c itie s o f the w e t surface and the acoustic ra dia tio n e ffic ie n c y are adopted as the m ain indexes to estim ate th e aco ustic ra d ia tio n a b ility from the subrou tin e stru ctu re s and th e c h a ra c te ris tic s o f the v ib ra tio n and aco ustic ra d ia tio n from the w h o le stru c tu resyste m ica lly. In the c a lc u la tio n ab ou t the flu id , the 耶mesh su p e rp o sitio n m e th o d爷 is used to im prove thec a lc u la tin g e ffic ie n c y . B y a d ju s tin g th e c a b in d iv is io n m ethod, in some fre q u e n c y band, th e peak v a lu e fre quen cies o f th e tra n s fe r fu n c tio n s o f the v ib ra tio n and aco ustic ra d ia tio n are changed, and th e peak v a lu e isreduced. The resu lts show th a t the aco ustic c h a ra c te ris tic s o f th e c a b in s tru c tu re can be changed by a d ju s tingth e above m ethod, so th a t th e e x c itin g fo rce o f th e m a ch in es and th e sp e c tra l pe ak fre q u e n c ie s o f thetra n s fe r fu n c tio n s are separated, as a resu lt, the noise and v ib ra tio n are c o n tro lle d .