Kalinova Klara
Technical University of Liberec; The Institute for Nanomaterials, Advanced Technology and Innovation, Studentska 2; 46117 Liberec; Czech Republic.
Recent Pat Nanotechnol. 2015;9(1):61-9. doi: 10.2174/187221050901150311102407.
As absorption of sound of lower frequencies is quite problematic with fibrous material made up of coarser fibers, development of highly efficient sound absorption material is called for. This is why this work deals with the development of new high sound absorption material. To absorb the low frequencies, especially the structures based on resonance principle of nanofibrous layers are used, when through resonance of some elements the acoustic energy is transferred into thermal energy. The goal of the invention is achieved by a sound absorbing means which contains resonance membrane formed by a layer of polymeric nanofibers, which is attached to a frame. For production of nanofibrous membranes, the cord electrospinning was used. The resonance membrane was then, upon impact of sound waves of low frequency, brought into forced vibrations, whereby the kinetic energy of the membrane was converted into thermal energy by friction of individual nanofibers, by the friction of the membrane with ambient air and possibly with other layers of material arranged in its proximity, and some of the energy was also transmitted to the frame, through which the vibrations of the resonance membrane were damped. The density and shape of the mesh of frame formations determine the resonance frequency of the acoustic means. The goal of the invention is therefore to eliminate or at least reduce the disadvantages of the present state of the art and to propose sound absorbing means that would be capable of absorbing, with good results sounds in as broadest frequency range as possible. Here, we also discussed some patents relevant to the topic.
由于由较粗纤维组成的纤维材料对低频声音的吸收存在很大问题,因此需要开发高效的吸声材料。这就是为什么这项工作致力于新型高吸声材料的开发。为了吸收低频,特别是使用基于纳米纤维层共振原理的结构,通过某些元件的共振将声能转化为热能。本发明的目的通过一种吸声装置来实现,该装置包含由一层聚合物纳米纤维形成的共振膜,该共振膜附着在框架上。为了生产纳米纤维膜,采用了帘式静电纺丝技术。然后,在低频声波的冲击下,共振膜被迫振动,由此膜的动能通过单个纳米纤维之间的摩擦、膜与周围空气以及可能与其附近排列的其他材料层之间的摩擦转化为热能,并且一些能量也传递到框架上,通过框架来衰减共振膜的振动。框架结构的网格密度和形状决定了声学装置的共振频率。因此,本发明的目的是消除或至少减少现有技术的缺点,并提出一种能够在尽可能宽的频率范围内良好吸收声音的吸声装置。在此,我们还讨论了一些与该主题相关的专利。