The Disc Pump is a revolutionary, ultrasonic, pneumatic piezoelectric micropump that generates pressure or vacuum in a small, silent, vibration-free form factor. Designed for highly accurate, ultra-smooth, flow control, Disc Pump delivers unrivalled pneumatic performance and enables innovation wherever precision control of small volumes is critical. While not intended to flow liquids directly, its infinite turn down ratio and pulsation-free flow allow the user to control liquids indirectly via an air-over-liquid method. The disc pump allows you to generate and control a head pressure (air) with unprecedented resolution, resulting in impeccable precision liquid dispensing or displacement (lab-on a chip). The Lee Company works with a wide range of customers who use disc pumps as an air pressure source for fluid handling applications.
In this article, we look at how—in combination with a small number of off-the-shelf items—the Piezoelectric Disc Pump Development Kit can easily be configured to provide a range of fluid control regimes. The Piezoelectric Disc Pump Development Kit enables the rapid evaluation of one or multiple pumps, together with solenoid valves, making it easy to test system-level prototypes and evaluate the unique features of the Disc Pump technology.
High-precision liquid flow control is critical in many workflows, for example where it has a significant impact on reaction kinetics, detection rate, hydrodynamic processes (e.g. droplet generation) and so on.
For certain applications, the ability to create controlled oscillatory flow is also valuable. For example, Organ on a Chip systems often strive to mimic physiological processes, such as pulsatile blood flow or the cyclic stress that lung tissue undergoes during the breathing cycle.
The Piezoelectric Disc Pump Development Kit can be connected directly to a liquid flow sensor (in this case, a Sensirion Liquid Flow Sensor) to allow closed-loop flow rate control from µL/min to ml/min, as outlined in Schematic A below. The video below shows a demonstration of the liquid flow rate achieved when applying an oscillatory power profile when using the disc pumps, as well as closed-loop control of an oscillatory liquid flow profile at different control loop parameters.
Demonstrates a Fluid Flow Control system using the Piezoelectric Disc Pump Development Kit, including a Sensirion Liquid Flow Sensor. “SDC” is a series configuration disc pump (e.g. XP-S2-028 or BL-S2-030)
The pump can be operated with a sealed volume and a pressure sensor to create a compact, low cost air displacement pipette system for aspiration/dispense and dosing applications. In the video below, featuring early testing with a Development Kit and simple pneumatic components as outlined in Schematic B, demonstrates how aspiration and dispense speed can be controlled by adjusting the pump drive power, allowing for precise control.
Demonstrates a closed-loop system with the Piezoelectric Disc Pump Development Kit and a sealed volume and pressure sensor. “PDC” is a parallel configuration disc pump (e.g. XP-P2-029 or BL-P2-031)
Controlling the position of fluid moving through a system with precision and repeatability is a necessity in many fluidic systems.
In this third demonstration, the rapid response of the pump is illustrated by controlling the position of a slug of fluid in a microfluidic chip. In the video below, we use a vision system to determine when to stop and start the fluid, and a simple flow reversal circuit that allows a single pump to ‘push or pull’ the fluid between points C1 & C4. At points C2 and C3, the pump power is reduced to achieve a ‘slow approach’ to avoid overshoot.
This is achieved using the Piezoelectric Disc Pump Development Kit with a small number of off-the-shelf components, outlined in Schematic C below.
Demonstrates a reversible airflow system with the Piezoelectric Disc Pump Development Kit and some off-the-shelf components. “SDC” is a series configuration disc pump (e.g. XP-S2-028 or BL-S2-030)
All three demonstrations were put together with the Piezoelectric Disc Pump Development Kit and a small number of off-the-shelf components. If you are looking for further information on how to integrate these designs in your own systems, please contact us to discuss your requirements.
Get your Piezoelectric Disc Pump Development Kit and start testing the capabilities and exploring the functionality of the Lee Disc Pump and solenoid valves.
Always verify flow calculations by experiment.
*There are many parameters to consider when determining V-Factor. Click here for more information.