Heat exchanger cooling fin

1. A heat exchanger cooling fin for use in a fluid flow environment, comprising a fin plate having a series of substantially mutually parallel louvres each louvre having two opposite open edges such that adjacent open edges of adjacent louvres define a flow aperture, each louvre having a convex curved surface that faces in the opposite direction to a convex curved surface of each adjacent louvre, said series of louvres defining a nominal fluid flow path along the series over said convex curved surface of each louvre

wherein said louvres are arranged such that fluid flowing from a first side of said fin plate through a first flow aperture to the second side of the fin plate and over a first louvre, follows a curved contour of the convex surface of said first louvre through a second flow aperture to the first side of the fin plate and over the convex curved surface of a second louvre adjacent to said first louvre.

2. A heat exchanger cooling fin according to claim 1 , comprising a channel configured to partially or fully receive tubing therein.

3. A heat exchanger cooling fin according to claim 2 , comprising a channel configured to partially receive tubing therein configured to enable tubing to push fit therein.

4. A heat exchanger having a heat exchanger cooling fin according to claim 1 , for use in a fluid flow environment, said heat exchanger cooling fin comprsing a fin plate having a series of louvres arranged to direct fluid flow from a first side of said fin plate to the second side of the fin plate and back to said first side of the fin plate, and said heat exchanger comprising tubing in heat transfer contact with the fin plate, said tubing extending in a direction along said series of louvres.

5. A heat exchanger having a heat exchanger cooling fin according to claim 1 , for use in a fluid flow environment, said heat exchanger cooling fin comprising a fin plate having a series of louvres arranged to direct free convection fluid flow from a first side of said fin plate to the second side of the fin plate and back to said first side of the fin plate.

6. A heat exchanger cooling fin according to claim 1 , wherein the open edges of each louvre are offset from a nominal plane of the fin plate, and the convex curved surface of each louvre extends from said edges away from the nominal plane.

7. A heat exchanger comprising a cooling fin for use in a fluid flow environment, said cooling fin comprising a fin plate having a series of substantially mutually parallel louvres each louvre having two opposite open edges such that adjacent open edges of adjacent louvres define a flow aperture, each louvre having a convex curved surface that faces in the opposite direction to a convex curved surface of each adjacent louvre, said series of louvres defining a nominal fluid flow path along the series over said convex curved surface of each louvre,

wherein said louvres are arranged such that fluid flowing from a first side of said fin plate through a first flow aperture to the second side of the fin plate and over a first louvre, follows a curved contour of the convex surface of said first louvre through a second flow aperture to the first side of the fin plate and over the convex curved surface of a second louvre adjacent to said first louvre.

8. A heat exchanger according to claim 7 , wherein said cooling fin comprises a channel and said heat exchanger further comprises tubing partially or fully received within said channel.

9. A heat exchanger according to claim 8 , wherein said tubing is a push fit within said channel of said cooling fin.

10. A heat exchanger according to claim 7 , wherein the open edges of each louvre are offset from a nominal plane of the fin plate, and the convex curved surface of each louvre extends from said edges away from the nominal plane.

11. A heat exchanger according to claim 7 , comprising tubing in heat transfer contact with the fin plate, said tubing extending in a direction along said series of louvres.

12. A heat exchanger according to claim 7 , wherein said cooling fin comprises a fin plate having a series of louvres arranged to direct free convection fluid flow from a first side of said fin plate to the second side of the fin plate and back to said first side of the fin plate.

13. A heat exchanger according to claim 7 , comprising tubing in heat transfer contact with said cooling fin, wherein the heat exchanger comprises a plurality of fin plates and the tubing between adjacent fin plates is bent such that a fin plate is arranged to be substantially parallel with the other fin plates.

14. A refrigeration unit having a heat exchanger according to claim 7 , wherein said heat exchanger is a condenser.

15. A refrigeration unit having a heat exchanger cooling fin according to claim 7 , wherein said heat exchanger is positioned substantially vertically in air, such that air flows along said nominal fluid flow path by convection.

16. A refrigeration unit having a heat exchanger cooling fin according to claim 7 , wherein said refrigeration unit comprises a fan configured to provide a forced flow of air to said heat exchanger cooling fin.

17. A heat exchanger cooling fin for use in a fluid flow environment, comprising a fin plate having a series of substantially mutually parallel louvres each louvre having two straight edges and a convex surface curved from one such edge to the other and facing in the opposite direction to the convex curved surface of each adjacent louvre,

wherein edges of adjacent louvres define a flow aperture of generally uniform width along said edges, said series of louvres defining a nominal flow path along the series over said convex curved surface of each louvre.

18. A heat exchanger cooling fin for use in a fluid flow environment as claimed in claim 17 wherein said edges are spaced from said fin plate with each edge of a fin positioned on the opposite side of said plate from an edge of an adjacent fin.

19. A heat exchanger comprising a cooling fin for use in a fluid flow environment, comprising a fin plate having a series of substantially mutually parallel louvres each louvre having two straight edges and a convex surface curved from one such edge to the other and facing in the opposite direction to the convex curved surface of each adjacent louvre, wherein edges of adjacent louvres define a flow aperture of generally uniform width along said edges, said series of louvres defining a nominal flow path along the series over said convex curved surface of each louvre.

20. A heat exchanger according to claim 19 , wherein said cooling fin comprises a channel and said heat exchanger further comprises tubing partially or fully received within said channel.

21. A heat exchanger according to claim 20 , wherein said tubing is a push fit within said channel of said cooling fin.

22. A heat exchanger according to claim 19 , wherein the open edges of each louvre are offset from a nominal plane of the fin plate, and the convex curved surface of each louvre extends from said edges away from the nominal plane.

23. A heat exchanger as claimed in claim 19 wherein said edges are spaced from said fin plate with each edge of a fin positioned on the opposite side of said plate from an edge of an adjacent fin.