Real g-level for all Coil Planet Centrifuges
At the Brunel Institute for Bioengineering we have developed a high speed Non-Synchronous CCC machine where the rotational speed of the bobbin (containing the coil) and rotor can be adjusted independently. Doing this mixing and settling inside the coil can be changed independently which might be required for certain applications.|
This application was developed together with a publication describing the g-level calculations for all coil planet centrifuges (or the Non-Synchronous CCC machine) to enable anyone to understand the g-level values in a coil planet centrifuge.
In the left hand picture the blue line shows the path of the rotor, the green line shows the coil at a particular diameter and the path of one point on the coil at that diameter (also called the locus) is shown in the red line.
In the right hand picture the red lines show the radial and tangential g-levels, the blue lines show the maximum and minimum radial g-level values, the green line shows the mean radial g-level value and the black lines show the rotor g-level value and the g-level value of 0.
The β-value (β) of a coil is defined as the diameter of the coil (r) in the bobbin over the diameter of the rotor (R). This β-value can be changed to see how different coil diameters affect the path of one point on the coil.
Changing the ratio of the bobbin to rotor speed (Pr) shows the different paths that can be achieved with the Non-Synchronous centrifuge. When Pr = 1 the machine behaves as a J-type centrifuge which this is most common type of centrifuge. When the Pr = -1 the machine behaves as an I-type centrifuge which is a centrifuge with a belt drive. When Pr = 2 the bobbin rotates twice for every rotor rotation which gives more mixing and faster settling compared to the J-type. When Pr = 0.5 the bobbin rotates once for two rotor rotations which gives more settling and faster mixing compared to the J-type.
Please try the application by entering different values for Pr (from -5.0 to 5.0) and B (from 0 to 1) and press the button to calculate and animate the result.