Microfluidics application note
Published on 17 December 2020
This application note describes:
- How to calculate the flow rate at stake in your microfluidic device
- The resulting shear stresses & the microfluidic resistances occurring in your channel.
Elveflow’s online microfluidic calculator has been designed to help researchers and especially non-specialists of the microfluidics field. It helps you assess key parameters to configure your microfluidic experiment.
Check out our dedicated tutorial with Kalyan Veerendra!
It should be noted that every microfluidic chip and setup are different. Here, we use a generic microfluidic system to give you a basic understanding of the parameters to select the right components for your setup.
Here are some of the many applications made easier by this calculator:
- Droplet generation and manipulation
- Alginate monodisperse droplet beads production
- Microfluidic perfusion for dynamic cell culture
Please note that each microfluidic system is different and the differences within the overall system, like the specific design of the chip will likely have an impact on the calculations performed using the tool. t is likely that the actual parameters would vary based on the real world experimental conditions. It’s always good to recalculate each time you make adjustments to your parameters.
How to calculate flow rate with the microfluidic calculator?
Reminder: Key experimental parameters
- The pump or pressure source
Exp: OB1 Mk3+ pressure-driven flow controller. - The microfluidic device
- The tubings
For more understanding of the working principle of pressure-driven flow controlled microfluidics, watch the following video.
All those elements will impact the calculation of your flow rate and the microfluidic resistance of your system. For more insight into those parameters, please refer to this application note.
Detailed protocol
1/ Enter your fluid properties
Please refer to the application note: how to implement/convert the fluid properties inside my reservoir.
You can select from either the drop down menu of the commonly used fluids in microfluidics, or custom parameters for viscosity and density.
For the sake of this demo, we will use medium with 10% serum, most commonly used.
2/ Enter Tubing resistance [Optional]
Please refer to the application note: how to take into account the tubing resistance if high compared to your chip. For this demonstration, we will consider it as negligible.
3/ Choose your model geometry
The third part of the calculation is related to the geometry of the channel inside the chip. Theses parameters play an important role in the calculation of the shear stress within the channel.
The channels are most commonly circular or rectangular.
- Select the channel type you are using.
In this demonstration, the IBIDI chip has a rectangular geometry.:
- Width: 5000 um
- Height: 400 um
- Length: 50 mm
[ob1f_rebound]
4/ … Calculate flow rate!
You can chose to enter the flow rate targeted into your chip, the pressure or the shear stress at the wall of your microfluidic channel you want to achieve.
Here, a fixed flow rate: 1000 µL/min (1 mL/min) was entered and automatically, we have results for the pressure to apply and the shear stress.
Reciprocally, you can enter the pressure and estimate the resulting flow rate!
The OB1 pressure controller is commonly configured to work in ranges of 0-200 or 0-2000 mbar.
Warning! As you can see, 0.23 mbar is very low. A steady flow rate will be hard to achieve without adding resistance.
5/ Get additional advice!
In the advice section, the calculator recommends to add microfluidic resistance to have a higher pressure to apply and a more stable flow.
Different inner diameter values are proposed and the related length of it to achieve 100 mBar.
Here, we will use a 250 um ID (Inner Diameter) with 8 cm before the chip. We will enter theses resistance values into the Part 2 section.
We can see the calculator automatically updates the calculations with data from Part 2.
The shear stress result is in accordance with the experimental data given by the IBIDI datasheet.
- To discover how to calculate your microfluidic resistance, please read our related application note!
- Click here to convert your microfluidic units with our dedicated application note!
Also, the calculator gives you recommendations on:
- flow sensor (Gas or liquid flow sensors)
- pressure-driven flow controller
For the full Elveflow microfluidic product line, please watch the following video !
You can save your data and send it to your own inbox!
Get started calculate now the flow in your microfluidic chip!
Need more information? Contact our team of experts!
Microfluidics knowledge
Do you want tips on how to best set up your microfluidic experiment? Do you need inspiration or a different angle to take on your specific problem? Well, we probably have an application note just for you, feel free to check them out!
Job
Collaborations
Customer
Other
