Application Cases

Experiment Name: Application of Power Amplifier in Schlieren-Based Acoustic Visualization Experiments

Research Direction: Acoustic Metasurface and Acoustic Invisibility Cloak

Experimental Content:
Using a schlieren visualization platform, the outgoing plane waves of the designed acoustic invisibility cloak were measured. An Aigtek power amplifier was employed to drive the planar ultrasonic array, generating ultrasonic waves with well-collimated wavefronts and precise controllability within the waveguide.

Test Objective: To validate the wavefield pattern of the outgoing acoustic waves

Testing Equipment: Signal generator, power amplifier (ATA-2021H), oscilloscope, computer, etc.

Experimental Procedure:

1. A square wave ultrasonic signal with a frequency above 20 kHz was generated by the signal generator and amplified using the ATA-2021H power amplifier.

2. The amplified ultrasonic signal was then input into the ultrasonic transmitter array.

3. A dual-channel signal generator was used to simultaneously drive the LED stroboscopic light source and the undistorted ultrasonic signal after amplification.

4. By leveraging the "minute frequency difference" between the two devices, visualization of the tested acoustic waves was achieved.

The schematic diagram of the experimental principle is shown below:

Test Results:

The test results successfully met the requirements for acoustic visualization research. The required frequency difference in the experiment was extremely small, a challenge that was difficult to achieve with previously self-designed PCB digital amplifiers. The precision of the ATA-2021H power amplifier enabled undistorted amplification of arbitrary waveforms with a frequency difference as small as a few Hertz. Furthermore, the amplified ultrasonic signal reached a peak-to-peak voltage of 200 Vmax, allowing the ultrasonic array to operate at maximum power. This facilitated the generation of visualized outgoing acoustic field patterns as depicted in the research literature.

Key Results:

Figure: ATA-2021B High-Voltage Amplifier Specifications and Parameters