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 Evaluation 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 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 Evaluation 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.
The video shows some early testing we carried out using an Evaluation Kit and a few simple pneumatic components, as outlined on in Schematic B below.
As shown in the video, aspiration and dispense speed can be adjusted by varying the pump drive power, providing a high degree of control. We looked at this this topic in more detail in our previous blog post Pipetting with Disc Pumps – Key Learnings.
Demonstrates a closed-loop system with the Piezoelectric Disc Pump Evaluation 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 this video 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 Evaluation 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 Evaluation 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 Evaluation kit with 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. Alternatively, if you are looking to test and explore the disc pump technology you can find out more about our Evaluation Kit here.