Simulation of Acoustic Characteristics in the Vector-Phase Field of the Horn at Low Frequencies

Methods of computer technology are widely used in modern acoustics. They are used to visualize the structures of wave fields, when the geometry of the boundaries and the physical properties of the region where the waves propagate are known. When using these methods, the location of the emitters and receivers is usually controlled. At present, known methods based on the use of information recorded only by pressure transducers have reached the limit. Vector-phase characteristics methods have previously been used to study the spatial distribution of the main characteristics of sound and infrasonic fields. But to study the structure of the acoustic field in the speakers of finite length, they have not been used so far. This is the relevance of the chosen topic. In this work the research of acoustic characteristics of a catenoid loudspeaker at low frequencies and a vector - phase field of a loudspeaker by numerical methods is given. The following tasks are solved: compiling an analytical review of research methods of sound fields; description of the mathematical apparatus of wave propagation in the catenoid mouthpiece; simulation of acoustic characteristics in the vector - phase field of the loudspeaker at low frequencies in ANSYS. In loudspeakers, nonlinear distortions associated with the heterogeneity of the magnetic field in the gap of the magnetic circuit and, in violation of Hooke's law, are not so significant. The defining moment in the development of the theory of wave radiation by loudspeakers was the publication of Webster's work, in which the wave equation is given. Although the membrane performs a simple harmonic oscillation. The problem of amplifying the action and direction of the acoustic signal was solved, during which a catenoid horn was chosen. The propagation of the wave is no longer sinusoidal, and contains in addition to the main harmonics of higher orders. That is, nonlinear effects inside the speaker are detected. Previously, the design of sound generators did not provide structural elements that reduce or eliminate completely nonlinear effects in the speaker, which reduced the efficiency of generating the sound of the fundamental tone. The solution of the problem of modeling the process of propagation of the second harmonic along the horn is considered. In order to calculate the acoustic characteristics in the cavity of the catenoid loudspeaker, it is necessary in ANSYS CAD.