Analysis of valveless micropumps: an integrated approach

Today there is a rising interest in the study of microfluidic systems. One of the main driving forces in this research area is integration of different components to have a chemical or biological analysis system on a single chip, which is called lab-on-achip system. Further development of lab-on-a-chip and micro liquid-cooling systems depend on micropumping technology. Therefore, a reliable and robust pumping technology is required for these and many other applications. Micropumps are one of the basic components of microfluidic systems and there have been several attempts to understand their underlying physics in order to improve the performance of these miniaturized devices. Most of these attempts were based on experimental work. Many different types of micropumps have been developed and studied by different research groups. One type is valveless diaphragm micropump (hereafter VDM), which in its simplest form consists of one pump chamber connected via one or more rectifying elements to an external system. The most common type of rectifying element in VDM is diffuser/nozzle element. To understand the behavior of VDMs the multi-physic nature of these devices should be investigated. An integrated approach is implemented to understand the behavior of VDMs, which consists of analytical and computational studies of the device. Analytical models (fluid dynamics and fluid-structure interaction) of different configurations of VDMs have been developed to relate physical properties of these systems to their performance characteristics. Computational studies for both fluid dynamics (CFD) and structural mechanics have been performed to establish a methodology for design and optimization of VDMs and facilitate their design process. The analytical results are compared to computational and published experimental results to investigate their correlation