چكيده به لاتين
Cloaking has always been an interesting subject for human beings as they tried to hide themselves from external threats. In recent years, breakthroughs and progress in the marine technology have underlined the importance of hiding from sound waves. Electromagnetic cloaking or light cloaking has a long history, but in the recent decade the discovery of similarities between acoustic and electromagnetic has paved the way for the progress in the field of acoustic cloaking. The goal in acoustic cloaking is to prevent the incoming waves from colliding with the target object and minimize of the acoustic reflection from the target object.
Different theories have been proposed for acoustic cloaking, among which conversion of inertia and pentamode coordinate system has gained popularity due to its comprehensiveness. The most important aspect of a cloaking theory is the ability to manufacture the required material for cloaking. In the field of underwater cloaking pentamode has exhibited suitable characteristics and is regarded as the leading theory in the field underwater cloaking.
Cloaking theories give information regarding the required features for cloaking; however, they do not reveal any information about the suitable structure and dimensions. However, it is possible to form an initial guess and optimize its dimensions to achieve parameters close to the ones of the cloaking theories in order to design the structure of the cloaking device.
Researchers have proposed various structures and methods for designing pentamode cloaks, among which using the Floquet-Bloch border condition is the most recent theory for obtaining the effective parameters of the structure, yet non proposed a method for optimization of the dimensions.
This research aims to model different methods of converting inertia and pentamode coordinate to undertake an accurate assessment of strengths and weaknesses of the methods as well as improving the Floquet-Bloch border condition and optimization methods for designing a pentamode cloaking device.
To realize this goal, in this study, using a link between Matlab and Comsol a method for identification of the effective parameters of a pentamode structure and optimization of its dimensions has been proposed. In the proposed method, metaheuristic algorithms such as Particle Swarm Optimization and Genetic Algorithm have been utilized to satisfy the parameters of pentamode theory. Finally, the effectiveness of the proposed method is verified using a two-dimensional cloaking device.
Keywords:Acoustic cloaking,optimization,pentamode cloaking,genetic alghoritem
