Panel filter with reduced restriction

1. A filter assembly comprising a housing having an inlet and an outlet, a panel filter element in said housing for filtering fluid flowing from said inlet to said outlet, said panel filter element dividing said housing into an inlet plenum and an outlet plenum, said panel filter element being configured to: a) reduce inlet flow restriction from said inlet, to said inlet plenum; and b) reduce outlet flow restriction from said outlet plenum to said outlet, wherein fluid flows along an axial direction in at least one of said inlet and outlet plenums, and flows transversely through said panel filter element from said inlet plenum to said outlet plenum, said inlet plenum and said outlet plenum are transversely spaced on opposite sides of said panel filter element therebetween, wherein said panel filter element extends obliquely relative to said axial direction, and wherein the volume of said inlet plenum increases as fluid progresses away from said inlet, and the volume of said outlet plenum decreases as fluid progresses towards said outlet.

2. The filter assembly accordingly to claim 1 wherein said housing comprises a base and a cover meeting, at an interface split line, and said panel filter element has a border frame with a mounting flange mounting said panel filter element to said housing at said split line and sealing said outlet plenum from said inlet plenum.

3. The filter assembly according to claim 1 wherein said panel filter element is rectiplanar.

4. The filter assembly according to claim 1 wherein said panel filter element is non-rectiplanar.

5. The filter assembly according to claim 4 wherein said panel filter element has at least one curved section.

6. The filter assembly according to claim 5 wherein said panel filter element has at least two curved sections.

7. The filter assembly according to claim 1 wherein said panel filter element is S-shaped and has a transition section between two curved sections, said transition section having an upstream face facing said inlet across said inlet plenum, and a downstream face facing said outlet across said outlet plenum.

8. A filter assembly comprising a housing having an inlet and an outlet, a panel filter element in said housing for filtering fluid flowing from said inlet to said outlet, said panel filter element dividing said housing into an inlet plenum and an outlet plenum, said panel filter element being configured to: a) reduce inlet flow restriction from said inlet to said inlet plenum; and b) reduce outlet flow restriction from said outlet plenum to said outlet, wherein said panel filter element has a border frame having distally opposite first and second endwalls, said first endwall being proximate said inlet, said second endwall being proximate said outlet, each said endwall having a height extending along the direction of fluid flow through said panel filter element, wherein the height of said first endwall is different than the height of said second endwall.

9. The filter assembly according to claim 8 wherein the height of said first endwall is greater than the height of said second endwall.

10. The filter assembly according to claim 8 wherein said panel filter element has a height along the direction of fluid flow therethrough, and wherein the height of one of said first and second endwalls is greater than the height of said panel filter element, and the height of the other of said first and second endwalls is less than the height of said panel filter element.

11. A filter assembly comprising a housing having an inlet and an outlet, a panel filter element in said housing for filtering fluid flowing from said inlet to said outlet, said panel filter element dividing said housing into an inlet plenum and an outlet plenum, said panel filter element being configured to: a) reduce inlet flow restriction from said inlet to said inlet plenum; and b) reduce outlet flow restriction from said outlet plenum to said outlet, wherein fluid flows along an axial direction in at least one of said inlet and outlet plenums, and flows transversely through said panel filter element from said inlet plenum to said outlet plenum, said inlet plenum and said outlet plenum are transversely spaced on opposite sides of said panel filter element therebetween, and wherein said housing comprises a base and a cover meeting at an interface split line, and wherein at least one of said split line and said panel filter element extends obliquely relative to said axial direction, wherein said split line extends parallel to said axial direction, and said panel filter element extends obliquely relative to said axial direction.

12. A filter assembly comprising a housing having an inlet and an outlet, a panel filter element in said housing for filtering fluid flowing from said inlet to said outlet, said panel filter element dividing said housing into an inlet plenum and an outlet plenum, said panel filter element being configured to: a) reduce inlet flow restriction from said inlet to said inlet plenum; and b) reduce outlet flow restriction from said outlet plenum to said outlet, wherein fluid flows along an axial direction in at least one of said inlet and outlet plenums, and flows transversely through said panel filter element from said inlet plenum to said outlet plenum said inlet plenum and said outlet plenum are transversely spaced on opposite sides of said panel filter element therebetween, and wherein said housing comprises a base and a cover meeting at an interface split line, and wherein at least one of said split line and said panel filter element extends obliquely relative to said axial direction, wherein said split line and said panel filter element extend in non-parallel relation to each other.

13. A filter assembly comprising a housing having an inlet and an outlet, a panel filter element in said housing for filtering fluid flowing from said inlet to said outlet, said panel filter element dividing said housing into an inlet plenum and an outlet plenum, said panel filter element being configured to: a) reduce inlet flow restriction from said inlet to said inlet plenum; and b) reduce outlet flow restriction from said outlet plenum to said outlet, wherein fluid flows transversely through said panel filter element from said inlet plenum to said outlet plenum, said housing comprises a base and a cover meeting at an interface split line, said panel filter element has a border frame for mounting and sealing said panel filter element in said housing, each of said base and said cover has a respective set of shelves engaging and trapping said border frame in mounted and sealed relation therebetween at least one of said shelves being transversely spaced from said split line.

14. The filter assembly according to claim 13 wherein said shelves include transversely extending ribs engaging and supporting said border frame.

15. The filter assembly according to claim 13 wherein a given set of said shelves extend parallel to said panel filter element and engage said border frame in sealing relation.

16. The filter assembly according to claim 13 wherein a first given set of said shelves extend parallel to said panel filter element and engage said border frame in sealing relation, and a second given set of said shelves extend obliquely relative to said panel filter element and engage said border frame in sealing relation.

17. The filter assembly according to claim 13 wherein a first given set of said shelves extend parallel to said panel filter element and engage said border frame in sealing relation, and a second given set of said shelves extend obliquely relative to said panel filter element and engage said border frame in sealing relation, and a third given set of said shelves comprise transversely extending ribs engaging and supporting said border frame.