Hydrodynamic separator with optimal microchannel length
A hydrodynamic separator is configured to separate a liquid having dispersed particles. The separator has a substrate and a liquid channel defined by the substrate, where the liquid channel is configured to receive a liquid having a Reynolds number (Re) within the channel. The liquid channel has an inlet and an outlet and is curved to define an inner radius (R C ). The liquid channel has a liquid channel length (L D ) along the curve and a rectangular cross-section along the length of the curve, where the rectangular cross-section has a height, a width (w), and a hydraulic diameter (D H ). The liquid channel length (L D ) is greater than or equal to a linear focusing length (L f ), and L f = 1598.8 R c α w 2 Re D H 3 + 6 . 4 , where a is the particle diameter. The liquid channel length (L D ) is greater than or equal to a linear focusing length (Lf), and L f = 1 5 6 . 2 R c Re ( w D H ) 2 + 24.3 . In various embodiments the liquid channel length (L D ) is greater than or equal to a linear focusing length (L f ), and L f = Re w 2 8 D H + 2 4 . 3 .
1 . A hydrodynamic separator configured to separate a liquid having dispersed particles having a diameter (a) (μm) comprising:
a substrate;
a liquid channel defined by the substrate, the liquid channel configured to receive a liquid having a Reynolds number (Re) within the channel, the liquid channel having an inlet and an outlet, wherein:
the liquid channel is curved to define an inner radius (R C ) (mm) and has a liquid channel length (L D ) (mm) along the curve,
the liquid channel has a rectangular cross-section along the length of the curve,
the rectangular cross-section has a height (h) (μm), a width (w) (μm) that increases or decreases towards the outlet, and a hydraulic diameter (D H ) (μm),
the liquid channel length (L D ) (mm) greater than or equal to a linear focusing length (L f ), and
L
f
=
1598.8
R
c
a
w
2
R
e
D
H
3
+
6.4
,
when measured under conditions where the Reynolds number (Re) is less than 1000, a Dean Number (De) is between 5 and 25, and the diameter (a) is greater than 8% of the hydraulic diameter (D H ) and less than 50% of the height (h).
2 . The hydrodynamic separator of claim 1 , wherein the liquid channel length (L D ) is no greater than 30% more than the linear focusing length (L f ).
3 . The hydrodynamic separator of claim 1 , wherein the particles are up to three times as dense as the liquid.
4 . The hydrodynamic separator of claim 1 , wherein the outlet comprises a first outlet and a second outlet.
5 . A hydrodynamic separator configured to separate a liquid having dispersed particles comprising:
a substrate;
a liquid channel defined by the substrate, the liquid channel configured to receive a liquid having a Reynolds number (Re) within the channel, the liquid channel having an inlet and an outlet,
wherein:
the liquid channel is curved to define an inner radius (R C ) (mm) and has a liquid channel length (L D ) (mm) along the curve,
the liquid channel has a rectangular cross-section along the length of the curve,
the rectangular cross-section has a height (h) (μm), a width (w) (μm) that increases or decreases towards the outlet, and a hydraulic diameter (D H ) (μm), the liquid channel length (L D ) (mm) is greater than or equal to a linear focusing length (L f ), and
L
f
=
R
e
w
2
8
D
H
+
24.3
,
when measured under conditions where the Reynolds number (Re) is less than 1000, a Dean Number (De) is between 5 and 25, and the diameter (a) is greater than 8% of the hydraulic diameter (D H ) and less than 50% of the height (h).
6 . The hydrodynamic separator of claim 5 , wherein the liquid channel length (L D ) is no greater than 40% more than the linear focusing length (L f ).
7 . The hydrodynamic separator of claim 5 , wherein the particles are up to three times as dense as the liquid.
8 . The hydrodynamic separator of claim 5 , wherein the outlet comprises a first outlet and a second outlet.
9 . A hydrodynamic separator configured to separate a liquid having dispersed particles having a diameter (a), comprising:
a substrate;
a liquid channel defined by the substrate, the liquid channel configured to receive a liquid having a Reynolds number (Re) within the channel, the liquid channel having an inlet and an outlet,
wherein:
the liquid channel has a curved inner wall defining an inner radius (R C ) and a curved outer wall defining an outer radius, wherein the inner radius is constant from the inlet to the outlet,
the liquid channel has a liquid channel length (L D ) along the curved inner wall,
the liquid channel has a rectangular cross-section along the liquid channel length, and
the rectangular cross-section has a channel width (w) between the inner wall and outer wall,
where the channel has a tapered region where the channel width tapers between the inlet and the outlet.
10 . The hydrodynamic separator of claim 9 , wherein the width increases towards the outlet.
11 . The hydrodynamic separator of claim 9 , wherein the channel width increases at a constant rate between the inlet and the outlet.
12 . The hydrodynamic separator of claim 9 , wherein the width decreases towards the outlet.
13 . The hydrodynamic separator of claim 9 , wherein the outer radius tapers outward between the inlet and the outlet.
14 . The hydrodynamic separator of claim 9 , wherein the liquid channel has a first region having a first channel width and a first liquid channel length, a second region having a second channel width and a second liquid channel length, and the tapered region having a tapered region length that extends from the first region to the second region.
15 . The hydrodynamic separator of claim 14 , wherein the first region has a larger length than the second region.