Backward curved plenum fan having enhanced efficiency

Patent metadata

Field	Value
Publication number	US-11603856-B2
Application number	US-201916702144-A
Country	US
Kind code	B2
Filing date	Dec 3, 2019
Priority date	Dec 3, 2018
Publication date	Mar 14, 2023
Grant date	Mar 14, 2023

Abstract

A centrifugal fan for use as a blower in a heating, ventilation, air conditioning, and refrigeration (HVACR) system has a plurality of blades each having a leading edge camber angle of at or about 10 degrees to at or about 30 degrees, a trailing edge camber angle of at or about 10 degrees to at or about 30 degrees, a stagger angle of at or about 35 degrees to at or about 55 degrees, and a chord having a length L, wherein the length L over the diameter of the centrifugal fan divided by the diameter D satisfies the inequality 0.25≤L/D≤0.42. The fan blades having these parameters provide improved fan efficiency at certain operating conditions. The fan blades may further have a forward or radial sweep. The fan blades may have a uniform thickness from the leading edge to the trailing edge.

First claim

The invention claimed is:

1. A centrifugal fan blade assembly, comprising a fan wheel and a plurality of blades joined to the fan wheel, wherein each of the plurality of blades has a leading edge camber angle of 10 degrees to 30 degrees, a trailing edge camber angle of 10 degrees to 30 degrees, a stagger angle of 35 degrees to 55 degrees, and a chord having a length L, wherein the length L over a diameter D of the centrifugal fan blade assembly satisfies the inequality 0.25≤L/D≤0.42.

2. The centrifugal fan blade assembly of claim 1 , wherein each of the plurality of blades has a consistent thickness from a leading edge of the blade to a trailing edge of the blade.

3. The centrifugal fan blade assembly of claim 1 , wherein the centrifugal fan blade assembly comprises a plastic.

4. The centrifugal fan blade assembly of claim 3 , wherein the centrifugal fan blade assembly further comprises glass fill in an amount of 30% to 50% by mass.

5. The centrifugal fan blade assembly of claim 3 , wherein the plastic comprises nylon 6 or nylon 66.

6. The centrifugal fan blade assembly of claim 1 , wherein each of the plurality of blades comprises aluminum.

7. The centrifugal fan blade assembly of claim 1 , wherein each of the plurality of blades comprises steel.

8. The centrifugal fan blade assembly of claim 1 , wherein the leading edge camber angle is 10 degrees to 20 degrees.

9. The centrifugal fan blade assembly of claim 1 , wherein the trailing edge camber angle is 10 degrees to 20 degrees.

10. The centrifugal fan blade assembly of claim 1 , wherein the stagger angle is 46 degrees to 50 degrees.

11. The centrifugal fan blade assembly of claim 1 , wherein each of the plurality of blades has a maximum camber height at a point located from 40% to 60% of a distance from the leading edge to the trailing edge along a chord length of that blade.

12. The centrifugal fan blade assembly of claim 1 , wherein each of the plurality of blades has a maximum camber angle at a point located from 7% to 13% of the distance from the leading edge to the trailing edge along a chord length of that blade.

13. The centrifugal fan blade assembly of claim 1 , wherein each of the plurality of blades has a forward sweep of three to six degrees.

14. The centrifugal fan blade assembly of claim 1 , wherein each of the plurality of blades has a radial sweep of three to six degrees.

15. The centrifugal fan blade assembly of claim 1 , wherein the plurality of blades includes five or more blades.

16. The centrifugal fan blade assembly of claim 1 , wherein the chord has the length L of 195 mm to 215 mm.

17. The centrifugal fan blade assembly of claim 1 , further comprising a motor hub attachment.

18. A centrifugal fan, comprising a motor and the centrifugal fan blade assembly of claim 17 , wherein the centrifugal fan blade assembly is connected to the motor at the motor hub attachment.

19. A heating, ventilation, air conditioning and refrigeration (HVACR) system, comprising the centrifugal fan of claim 18 .

20. A method of operating a heating, ventilation, air conditioning and refrigeration (HVACR) system, comprising using a motor to drive rotation of a blade assembly comprising a fan wheel and a plurality of blades joined to the fan wheel, wherein each of the plurality of blades has a leading edge camber angle of 10 degrees to 30 degrees, a trailing edge camber angle of 10 degrees to 30 degrees, a stagger angle of 35 degrees to 55 degrees, and a chord having a length L, wherein the length L over a diameter D of the centrifugal fan blade assembly satisfies the inequality 0.25≤L/D≤0.42.

Assignees

• Trane Int Inc

Inventors

• Wagers Nathan
• Vedula Ramesh
• Sankar Ram Karthik
• Narayana Ganesh

Classifications

• F04D29/242

  Geometry, shape · CPC title

• F05D2300/603

  Composites; e.g. fibre-reinforced · CPC title

• F04D29/281 Primary

  for fans or blowers · CPC title

• F05D2300/121

  Aluminium · CPC title

• F04D29/023

  especially adapted for elastic fluid pumps · CPC title