Fluid flow labyrinth
A labyrinth channel for reducing pressure and/or flow rate in a liquid flowing in the channel, the labyrinth channel having a bottom surface and first and second opposing walls and comprising: a first array of spaced apart first baffle teeth that have non-parallel upstream and downstream faces and extend from the first wall towards the second wall to terminate in an end; and a second array of spaced apart second baffle teeth that have non-parallel upstream and downstream faces and extend from the second wall towards the first wall to terminate in an end; wherein baffle teeth in different arrays have a substantially same shape and upstream faces of closest baffle teeth in different arrays are different and/or downstream faces of closest baffle teeth in different arrays are different.
1. A labyrinth channel for reducing pressure and/or flow rate in a liquid flowing in the channel, the labyrinth channel having a bottom surface and first and second opposing walls and comprising:
a first array of spaced apart first baffle teeth that have non-parallel upstream and downstream faces and extend from the first wall towards the second wall to terminate in an end; and
a second array of spaced apart second baffle teeth that have non-parallel upstream and downstream faces and extend from the second wall towards the first wall to terminate in an end;
wherein
baffle teeth in different arrays have a substantially same shape; and
upstream faces of closest baffle teeth in different arrays have different orientations with respect to the walls from which they extend and/or downstream faces of closest baffle teeth in different arrays have different orientations with respect to the walls from which they extend.
2. A labyrinth channel according to claim 1 wherein ends of the first baffle teeth are contiguous with or intersect a same first surface that follows a contour of the labyrinth flow channel.
3. A labyrinth channel according to claim 2 wherein ends of the second baffle teeth are contiguous with or intersect a same second surface that follows a contour of the labyrinth flow channel.
4. A labyrinth channel according to claim 3 wherein the first and second surfaces that follow the channel contour are coincident.
5. A labyrinth channel according to claim 3 wherein the first and second surfaces that follow the channel contour are parallel and displaced one from the other.
6. A labyrinth channel according to claim 1 , wherein each tooth has a planar trailing-edge surface that makes an external angle β with the wall from which the tooth extends.
7. A labyrinth channel according to claim 6 wherein β has a value less than or equal to 100°.
8. A labyrinth channel according to claim 6 wherein β has a value greater than or equal to 80°.
9. A labyrinth channel according to claim 6 wherein β has a value substantially equal to 90°.
10. A labyrinth channel according to claim 6 wherein each tooth has a planar leading-edge surface that makes an included angle α with the trailing edge surface.
11. A labyrinth channel according to claim 10 wherein a has α value less than or equal to 45°.
12. A labyrinth channel according to claim 10 wherein a has α value greater than or equal to 15°.
13. A labyrinth channel according to claim 10 wherein the value of α is the same for all baffle teeth.
14. A labyrinth channel according to claim 6 wherein the value of β is the same for all baffle teeth.
15. A labyrinth channel according to claim 10 wherein one of the leading-edge and trailing-edge face surfaces of a tooth is an upstream face of the tooth.
16. A labyrinth channel according to claim 15 wherein if the upstream face of a first tooth is a leading-edge surface of the tooth, the downstream face of the nearest second tooth is the leading-edge surface of the second tooth.
17. A labyrinth channel according to claim 1 wherein the upstream and downstream faces of a first baffle tooth are respectively parallel with the downstream and upstream faces of a nearest second baffle tooth.
18. A labyrinth channel according to claim 17 wherein a distance between the upstream face of a first baffle tooth and a nearest downstream face of a second baffle tooth is equal to a same distance A between the downstream face of the first baffle tooth and the nearest upstream face of a second baffle tooth.
19. A labyrinth channel according to claim 18 wherein A is less than or equal to 3 mm.
20. A labyrinth channel according to claim 18 wherein A is greater than or equal to 0.3 mm.
21. A labyrinth channel according to claim 18 wherein the ends of the first and second teeth are located a same distance B from the respective walls from which they extend.
22. A labyrinth channel according to claim 21 wherein the channel has a width greater than 2B.
23. A labyrinth channel according to claim 21 wherein the channel has a width less than 2B.
24. A labyrinth channel according to claim 21 wherein the channel has a width substantially equal to about 2B.
25. A labyrinth channel according to claim 21 wherein B is greater than A.
26. A labyrinth channel according to claim 1 wherein the leading-edge and trailing-edge face surfaces intersect a common surface at different locations of the common surface to define an end surface of the tooth.
27. A labyrinth channel according to claim 26 wherein the common surface is planar.
28. A labyrinth channel according to claim 27 wherein the intersections of the leading and trailing edge surfaces are different parallel straight lines.
29. A labyrinth channel according to claim 1 wherein the labyrinth channel or portion thereof is straight.
30. A labyrinth channel according to claim 1 wherein the labyrinth channel or a portion thereof is circular.
31. A labyrinth channel according to claim 1 wherein the bottom surface of the labyrinth channel or portion thereof is substantially a circularly cylindrical surface.