INLET TUBE DESIGN

• US 20170370381A1
• Filed: 08/08/2017
• Published: 12/28/2017
• Est. Priority Date: 04/25/2014
• Status: Active Grant

• Current Assignee: Hamilton Sundstrand Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Hamilton Sundstrand Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Lucic, Milan, Beck, John M., Hamel, Paul E., Telakowski, Robert
• Granted Patent: US 10,641,294 B2
• Time in Patent Office: Days
• CPC Class Codes: B64D 13/00 Arrangements or adaptations of air-treatment apparatus for aircraft crew or passengers, or freight space , or structural parts of the aircraft treatment rooms with artificial climate for medical purposes A61G10/02; respiratory apparatus in general A62B; for vehicles in general B60H
• CPC Class Codes: B64D 13/06 the air being conditioned pressurising B64D13/02
• CPC Class Codes: B64D 2013/0618 with arrangements for reducing or managing bleed air, using another air source, e.g. ram air
• CPC Class Codes: B64D 2013/0651 comprising filters, e.g. dust filters
• CPC Class Codes: F04D 19/00 Axial-flow pumps F04D21/00 takes precedence; pump comprising axial flow and radial flow stages F04D17/025
• CPC Class Codes: F04D 25/06 the pump being electrically driven F04D25/08 takes precedence
• CPC Class Codes: F04D 29/5806 Cooling the drive system
• CPC Class Codes: F04D 29/701 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/703 specially for fans, e.g. fan guards
• CPC Class Codes: Y02T 50/50 On board measures aiming to increase energy efficiency

Abstract

A ram air fan assembly includes an outer housing. An inner housing is located within the outer housing. A motor is attached to the inner housing. An inlet tube extends between the outer housing and the motor. The inlet tube includes a straight first portion and a curved second portion. At least one of the two portions includes a perforated portion.

Claims

1. A method of filtration for use in a ram air fan assembly, the method comprising:

perforating a portion of an inlet tube with a plurality of perforations;

fluidly connecting a fan case with a motor with the inlet tube;

drawing an air flow through the inlet tube; and

spreading a suction force of the air flow across the perforated portion and a first end of the inlet tube.

2. The method of claim 1, the method further comprising;

decreasing the air flow entering the first end of the inlet tube.

3. The method of claim 2, the method further comprising:

preventing foreign object ingestion into the inlet tube.

4. The method of claim 1, wherein the inlet tube includes a first straight portion and a second curved portion, and further wherein perforating the inlet tube includes creating perforations along an entire first straight portion of the inlet tube.

5. The method of claim 1, wherein the inlet tube includes a first straight portion and a second curved portion, and further wherein perforating the inlet tube includes creating perforations along at least half of the straight first portion of the inlet tube.

6. The method of claim 1, wherein the inlet tube includes a first straight portion and a second curved portion, and further wherein perforating the inlet tube includes creating perforations along at least a portion of the curved second portion of the inlet tube.

7. A method of cooling, the method comprising:

drawing an air flow through a portion of an inlet tube of a ram air fan assembly, wherein the ram air fan assembly comprises;

an outer housing;

an inner housing located within the outer housing; and

a motor attached to the inner housing, wherein the inlet tube defines a portion of a flowpath leading to a downstream end of the inner housing and such that the inlet tube is fluidly connected to a downstream end of the motor, wherein the inlet tube comprises;

an inlet;

at least a straight first portion; and

a curved second portion, wherein the straight first portion and the curved second portion comprise a perforated portion with uniformly spaced perforations, wherein the perforated portion is fluidly connected to air within the outer housing;

spreading a suction force of the air flow across the perforated portion and a first end of the inlet tube.

8. The method of claim 7, wherein the inlet tube is configured to pull in ambient air.

9. The method of claim 8, further comprising pulling ambient air into the inlet tube.

10. The method of claim 8, further comprising reducing a suction force of the air flow entering into the inlet of the inlet tube.

11. The method of claim 8, further comprising drawing air flow from within the outer housing across the perforated portion and into the inlet tube.

12. The method of claim 8, further comprising filtering particulate from the air flow entering into the ram air fan assembly.

13. The method of claim 8, further comprising cooling the motor by flowing the air flow across at least one of thrust bearings, journal bearings, a motor stator, and a motor rotor of the motor.