Related Experiment Video
Updated: Jun 25, 2026
10:22
High Speed Droplet-based Delivery System for Passive Pumping in Microfluidic Devices
Published on: September 2, 2009
Computation of transient flow rates in passive pumping micro-fluidic systems
I-Jane Chen1, Eugene C Eckstein, Erno Lindner
1Department of Biomedical Engineering, The University of Memphis, Memphis, TN 38152, USA. ijchen@memphis.edu
Lab on a Chip
|February 12, 2009
Summary
This study models flow rate in passive pump microfluidic systems, considering droplet surface energy and geometry. The model accurately predicts flow rates influenced by experimental conditions, validated by experiments.
Area of Science:
- Microfluidics
- Fluid Dynamics
- Surface Science
Background:
- Passive flow microfluidic systems offer controlled fluid motion.
- Modeling flow rate is crucial for system design and performance.
- Surface energy of droplets drives flow in these systems.
Purpose of the Study:
- To develop a model describing time-dependent flow rate in passive pump microfluidic devices.
- To investigate the influence of droplet geometry and surface properties on flow.
- To provide a more specific model for flow rate computation based on experimental conditions.
Main Methods:
- Utilized interfacial thermodynamics and the Hagen-Poiseuille equation.
- Incorporated droplet surface energy and controlled geometries.
- Modeled flow rate as a function of time and experimental parameters.
Main Results:
- The model accurately describes flow rate influenced by microfluidic geometry and surface hydrophilicity.
- Experimental validation confirmed model predictions across various conditions.
- Observed initial flow rates ranging from 85 nL/s to 196 nL/s.
Conclusions:
- The developed model enhances the understanding of flow dynamics in passive microfluidic pumps.
- It offers improved prediction accuracy for flow rates under specific experimental setups.
- This work contributes to the precise design and application of microfluidic devices.
Related Concept Videos
01:27Steady Flow of a Fluid Stream
Consider a control volume, such as a pipe with solid boundaries, through which fluid flows and changes direction due to the impulse exerted by the resulting force from the pipe walls. In steady flow, the mass of fluid entering the control volume at a given time, t, with velocity v1, is equal to the mass leaving after infinitesimal time dt, with velocity v2.
During this process, the momentum of the fluid within the control volume remains constant over the time interval dt. By applying the...
During this process, the momentum of the fluid within the control volume remains constant over the time interval dt. By applying the...
01:28Pipe Flowrate Measurement: Problem Solving
A spray tank system is engineered to uniformly distribute a pest-control liquid across plants by using a pressurized mechanism. The tank, pressurized to 150 kPa, holds the pesticide at a height of 0.80 meters. Liquid flows from the tank through a 1.9 meter pipe with a diameter of 0.015 meters, angled at 0.698 radians, ultimately reaching a 0.007 meter nozzle that sprays the pesticide. Accurate calculation of the system's flow rate is crucial to ensure uniform application, and this is achieved...
01:22Couette Flow
Couette flow represents the flow of fluid between two parallel plates, with one plate fixed and the other moving with a constant velocity. This configuration allows for a simplified analysis using the Navier-Stokes equations, which govern fluid motion under conditions of viscosity and incompressibility. For Couette flow, the assumptions include a steady, laminar, incompressible flow with a zero-pressure gradient in the flow direction. This flow type is beneficial for understanding shear-driven...
01:28Pipe Flowrate Measurement
In pipe flow measurement, orifice, nozzle, and Venturi meters are commonly used to determine fluid flowrates by constricting the flow area, which increases fluid velocity and reduces pressure. This pressure difference, governed by Bernoulli's principle and adjusted for real-world conditions, is essential for calculating flowrate. Each meter type is suited to specific applications based on accuracy, efficiency, and compatibility with various flow conditions.
The orifice meter is a simple,...
The orifice meter is a simple,...
01:23Steady, Laminar Flow in Circular Tubes
Hagen-Poiseuille flow describes a viscous fluid's steady, incompressible flow through a cylindrical tube with a constant radius R. This flow profile is often applied to understand fluid transport in narrow channels, such as capillaries. It serves as a foundational example of laminar flow. In this model, cylindrical coordinates (r,θ,z) are used to describe the radial (r), angular (θ), and axial (z) dimensions within the tube. For Hagen-Poiseuille flow, the velocity profile is purely axial,...
01:17Steady, Laminar Flow Between Parallel Plates
Understanding steady, laminar flow between parallel plates is essential for analyzing and designing flow in narrow rectangular channels, commonly found in various water conveyance and drainage systems. The Navier-Stokes equations govern fluid motion and are generally challenging to solve due to their nonlinearity. However, simplifications are possible in certain cases, like the steady laminar flow between parallel plates. For this scenario, we assume steady, incompressible, laminar flow.