Low frequency acoustic excitation device

Abstract

A low-frequency sound wave excitation device comprises a liquid filling pipeline, wherein a pipe wall opening of the liquid filling pipeline is communicated with an outside closed cavity through a communicating cavity, a shell of the closed cavity and a shell of the communicating cavity are tightly fixed to each other and connected with each other in a sealed mode, and the closed cavity and the communicating cavity are communicated to form a measurement cavity. An excitation piston is connected with the inner wall of the measurement cavity in a sealed mode, the excitation piston is fixedly connected with a piston rod, the piston rod penetrates through the closed cavity and connected with the closed cavity in a sliding mode, the shell of the closed cavity is connected with the piston rod in a sealed mode, and a vibration exciter drives the excitation piston to slide in the measurement cavity through the piston rod, a gas inlet hole is formed in the closed cavity, the measurement cavity is divided into an upper cavity body and a lower cavity body through the excitation piston, the gas inlet hole is communicated with the upper cavity body, and furthermore an accelerometer is arranged on the connecting face between the hollow piston rod and the excitation piston. According to the low-frequency sound wave excitation device, sound radiation efficiency in a low-frequency region can be effectively improved, the acoustic performance testing requirement of a liquid filling pipeline component can be met, and the motion acceleration generated when the excitation piston is driven by the vibration exciter can be directly and accurately measured.

Description

technical field [0001] The invention relates to an excitation piston-type excitation device for a low-frequency acoustic wave field, in particular to a low-frequency acoustic wave excitation device applied to a liquid-filled pipeline, and in particular to a low-frequency acoustic wave excitation device applied to the acoustic performance test of liquid-filled pipeline components. Background technique [0002] When testing the acoustic impedance, acoustic transfer characteristics, insertion loss and other acoustic properties of liquid-filled pipeline components, it is necessary to introduce an external sound source to generate the required sound waves, so that the liquid-filled pipeline components in the sound field Under the excitation of sound waves, vibration is generated in order to obtain corresponding excitation and response. There are two main types of external sound sources currently used in fluid media: acoustic emission transducers and vibration exciters to excite p...

Images