Application Cases

Experiment Name: Ultrasonic-Driven Nozzle Microdroplet Preparation System

Experiment Content:
A novel ultrasonic-driven nozzle system integrating high-throughput microdroplet preparation and directional distribution functions was designed. The working mechanism of this system was analyzed through simulations and experiments, providing new insights for the design of highly integrated and controllable microdroplet manipulation systems.

Test Equipment: Signal generator, ATA-1372A broadband amplifier, oscilloscope, high-speed camera, etc.

Experimental Procedure:

Figure 1: Experimental Setup Diagram

The ultrasonic-driven nozzle system primarily consists of a capillary nozzle and a PZT transducer. When an AC electrical signal is applied to the PZT transducer, it generates acoustic waves, which propagate through the capillary to the nozzle tip, pumping liquid out of the nozzle. When modulated pulsed acoustic waves are transmitted into the liquid phase, intermittent acoustic streaming is produced. By controlling the driving time of the acoustic waves, the volume of liquid expelled from the nozzle, and consequently the size of the droplets formed, can be regulated. Additionally, when the input frequency is altered, the nozzle vibrates in different modes, generating acoustic streaming in various directions. By leveraging acoustic streaming in different directions, droplets can be subjected to directional traction forces, guiding them to corresponding positions.

Figure 2: Experimental Process

Experimental Results:

Figure 3: Experimental Result a

Figure 4: Experimental Result b

Apart from the ultrasonic driving time, the droplet size may also be determined by the driving amplitude. Therefore, by simultaneously controlling the driving time and amplitude, a wide-range, high-throughput droplet preparation system was achieved. In addition to droplet generation, controllable acoustic streaming can be used to guide droplets to different locations. By changing the input acoustic frequency, the direction of droplet motion can be altered from left to right. At different frequencies, the nozzle exhibits distinct vibration modes, leading to corresponding fluid flow patterns. Based on this mechanism, the distribution of droplets into different chambers can be controlled by adjusting the acoustic frequency.

Power Amplifier Recommendation: ATA-1372A

Figure: ATA-1372A Broadband Amplifier Specifications

The experimental materials in this article were compiled and published by Xi’an Aigtek Electronics.