High speed rotating crankcase ventilation filter media and media pack
Filter media and media packs that provide robust performance in high-speed rotating coalescer (HSRC) elements for crankcase ventilation systems are described. The fiber media is HSRC fiber media. As such, the filter media has a higher resistance to compressibility then traditional coalescer filter media, such as fiber media used in low-speed rotating coalescer arrangements or stationary coalescer arrangements.
1. A filter media comprising:
fibers having a geometric mean fiber diameter between 5 to 40 μm, the fibers having a solidity between 5% and 30%, and between 1% and 5% of the fibers having a diameter larger than 20 μm;
wherein the filter media has a compressibility of less than 25% at pressures greater than 20 kPa.
2. The filter media of claim 1 , wherein at least 1% to 5% of the fibers have a diameter larger than 40 μm.
3. The filter media of claim 1 , wherein about 3% of the fibers have a diameter larger than 30 μm.
4. The filter media of claim 1 , wherein the fibers are first fibers and the filter media comprises a first filter media layer comprising the first fibers, the filter media further comprising:
a second filter media layer disposed upstream or downstream of the first filter media layer, the second filter media layer comprising second fibers having a diameter greater than 30 μm.
5. The filter media of claim 1 , wherein the fibers are comprised of a polymeric material.
6. The filter media of claim 5 , wherein the polymeric material is a needle-punched polyphenylene sulfide filter media.
7. The filter media of claim 1 , wherein the filter media is formed into a cylindrical filter media pack.
8. The filter media of claim 7 , wherein the filter media has a compressibility of less than 25% at 200 G, where G is defined by the equation
G
=
ω
2
R
9
.
8
1
,
where ω is a rotational speed of the filter media pack in radians per second and R is a radius of the filter media pack in meters.
9. The filter media of claim 8 , wherein the filter media has a compressibility of less than 25% at 1000 G.
10. The filter media of claim 9 , wherein the polymer material is a single polymer material, a single copolymer material, or a single polymer blend.
11. The filter media of claim 1 , wherein the filter media has a Frazier permeability of less than or equal to 250 cubic feet per minute at 0.5 inches of water pressure drop.
12. The filter media of claim 1 , wherein the fibers are first fibers and the geometric mean fiber diameter is a first geometric mean fiber diameter, wherein the filter media further comprises second fibers having a second geometric mean fiber diameter, the second geometric mean fiber diameter different than the first geometric fiber diameter.
13. The filter media of claim 12 , wherein the second fibers are layered over the first fibers forming a multi-layer filter media.
14. The filter media of claim 12 , wherein the second fibers are positioned with respect to the first fibers such that the filter media has a varying filtering efficiency across a depth of the filter media thereby forming a gradient efficiency filter media.
15. The filter media of claim 12 , wherein the filter media is a composite filter media comprising the first fibers and the second fibers.
16. The filter media of claim 1 , wherein the compressibility is at 20 degrees Celsius.
17. The filter media of claim 1 , wherein the compressibility is at 120 degrees Celsius.
18. A filter media pack for use in a high-speed rotating coalescer, the filter media pack comprising:
filter media formed into a cylindrical filter media pack, the filter media having fibers of a polymeric material, the fibers having a geometric mean fiber diameter between 5 to 40 μm, the fibers having a solidity between 5% and 30%, and between 1% and 5% of the fibers having a diameter larger than 20 μm, the filter media has a compressibility of less than 25% at pressures greater than 20 kPa.
19. The filter media pack of claim 18 , wherein at least 1% to 5% of the fibers have a diameter larger than 40 μm.
20. The filter media pack of claim 18 , wherein about 3% of the fibers have a diameter larger than 30 μm.
21. The filter media pack of claim 18 , wherein the fibers are first fibers and the filter media comprises a first filter media layer comprising the first fibers, the filter media further comprising:
a second filter media layer disposed upstream or downstream of the first filter media layer, the second filter media layer comprising second fibers having a diameter greater than 30 μm.
22. The filter media pack of claim 18 , wherein the fibers having a Frazier permeability of less than or equal to 250 cubic feet per minute at 0.5 inches of water pressure drop.
23. The filter media pack of claim 18 , wherein the fibers are comprised of a polymeric material.
24. The filter media pack of claim 23 , wherein the polymeric material is a needle-punched polyphenylene sulfide filter media.
25. The filter media pack of claim 18 , wherein the filter media has a compressibility of less than 25% at 200 G, where G is defined by the equation
G
=
ω
2
R
9
.
8
1
,
where ω is a rotational speed of the filter media pack in radians per second and R is a radius of the filter media pack in meters.
26. The filter media pack of claim 25 , wherein the filter media has a compressibility of less than 25% at 1000 G.
27. The filter media pack of claim 18 , wherein the fibers are first fibers and the geometric mean fiber diameter is a first geometric mean fiber diameter, wherein the filter media further comprises second fibers having a second geometric mean fiber diameter, the second geometric mean fiber diameter different than the first geometric fiber diameter.
28. The filter media pack of claim 27 , wherein the second fibers are layered over the first fibers forming a multi-layer filter media.
29. The filter media pack of claim 27 , wherein the second fibers are positioned with respect to the first fibers such that the filter media has a varying filtering efficiency across a length of the filter media thereby forming a gradient efficiency filter media.
30. The filter media pack of claim 27 , wherein the filter media is a composite filter media comprising the first fibers and the second fibers.
31. A filter media comprising:
fibers having a geometric mean fiber diameter between 5 to 30 μm, the fibers having a solidity between 5% and 25%, and between 1% and 5% of the fibers having a diameter larger than 20 μm
wherein the filter media has a Frazier permeability of less than or equal to 250 cubic feet per minute at 0.5 inches of water pressure drop.
32. The filter media of claim 31 , wherein at least 1% to 5% of the fibers have a diameter larger than 40 μm.
33. The filter media of claim 31 , wherein about 3% of the fibers have a diameter larger than 30 μm.
34. The filter media of claim 31 , wherein the fibers are first fibers and the filter media comprises a first filter media layer comprising the first fibers, the filter media further comprising:
a second filter media layer disposed upstream or downstream of the first filter media layer, the second filter media layer comprising second fibers having a diameter greater than 30 μm.
35. The filter media of claim 31 , wherein the filter media has a compressibility of less than 25% at pressures greater than 20 kPa.
36. The filter media of claim 35 , wherein the fibers are of a polymeric material.
37. The filter media of claim 36 , wherein the filter media is formed into a cylindrical filter media pack.
38. The filter media of claim 37 , wherein the filter media has a compressibility of less than 25% at 200 G, where G is defined by the equation
G
=
ω
2
R
9
.
8
1
,
where ω is a rotational speed of the filter media pack in radians per second and R is a radius of the filter media pack in meters.
39. The filter media of claim 38 , wherein the filter media has a compressibility of less than 25% at 1000 G.