Hydrodynamic separation using high aspect ratio channels
A Hydrodynamic separation device using curved channels is provided. High aspect ratio channels improve the focusing dynamics of the hydrodynamic separator and leads to improved channel design choices.
1. A hydrodynamic separation device comprising:
an inlet for fluid containing particles;
a curved channel having a width and height and being configured to receive the fluid, wherein an aspect ratio of the width to the height of the channel is at least 7;
control elements including actuators configured to generate and maintain fluid flow such that the Dean number in the channel is between 30 and 100,
wherein multiple pairs of Dean vortices are generated in the fluid and Dean vortices nearest an outer channel wall carry particles in a concentrated band through the channel as a function of the Dean number and the aspect ratio; and,
an outlet configured to allow the concentrated stream to exit the channel on a first path and remaining fluid to exit the channel on a second path.
2. The device as set forth in claim 1 wherein the aspect ratio is 7.5.
3. The device as set forth in claim 1 wherein the aspect ratio is 15.
4. The device as set forth in claim 1 wherein the aspect ratio is between 8 and 15.
5. The device as set forth in claim 1 wherein the flow rate is adjusted such that the Dean number inside the channel is between 60 and 80.
6. The device as set forth in claim 1 wherein the aspect ratio is at least 15.
7. The system as set forth in claim 1 wherein the control elements or actuators comprise at least one of a control system, a pump, a valve, a user interface, a sensor and a variable frequency drive.
8. A method for hydrodynamic separation comprising:
receiving fluid containing particles in a curved channel having a width and height, wherein an aspect ratio of the width to the height of the channel is at least 7; and,
controlling the fluid in the channel using control elements having actuators such that the Dean number inside the channel is between 30 and 100 and to generate multiple pairs of Dean vortices in the fluid, wherein the Dean vortices nearest an outer channel wall carry particles in a concentrated band through the channel to an outlet configured to allow the concentrated stream to exit the channel on a first path and remaining fluid to exit the channel on a second path, as a function of the Dean number and aspect ratio.
9. The method as set forth in claim 8 wherein the aspect ratio is 7.5.
10. The method as set forth in claim 8 wherein the aspect ratio is 15.
11. The method as set forth in claim 8 wherein the aspect ratio is between 8 and 15.
12. The method as set forth in claim 8 wherein the flow rate is adjusted such that the Dean number inside the channel is between 60 and 80.
13. The method as set forth in claim 8 wherein the aspect ratio is at least 15.
14. The method as set forth in claim 8 wherein the control elements or actuators comprise at least one of a control system, a pump, a valve, a user interface, a sensor and a variable frequency drive.