System and method for scavenging ullage from center wing tanks in an airplane

• US 8,602,362 B2
• Filed: 10/08/2010
• Issued: 12/10/2013
• Est. Priority Date: 10/08/2010
• Status: Expired due to Fees

• Current Assignee: Simmonds Precision Products, Inc. (Rtx Corporation)
• Original Assignee: Simmonds Precision Products, Inc. (Rtx Corporation)
• Inventors: Buchwald, Philip Paul
• Primary Examiner(s): Ellis, Christopher P
• Assistant Examiner(s): Badawi, Medhat
• Application Number:
  US12/900,752
• Publication Number:
  US 20120087807A1
• Time in Patent Office: 1,159 Days
• Field of Search: 244/135.R, 137/209, 137/1, 220/88.3, 220/883, 417/54, 417/65
• US Class Current: 244/135.R
• CPC Class Codes: B64D 37/24 using gas pressure
• CPC Class Codes: B64D 37/32 Safety measures not otherwise provided for, e.g. preventing explosive conditions extinguishing or preventing fires in aircraft A62C

Abstract

A system for reducing reactive components in ullage of a fuel tank, typically the fuel tank of an airplane. The system includes an air driven unit for creating a fluidic motive force to remove ullage from the fuel tank, and a main catalytic unit for receiving the ullage and reducing the reactive components to yield processed ullage for return to the fuel tank.

Claims

1. A method for reducing reactive components in ullage of a fuel tank, the method comprising the steps of:

a) using ram air to create a fluidic motive force;

b) applying the fluidic motive force to the fuel tank to remove ullage;

c) providing the removed ullage to a main catalytic unit for reducing the reactive components to yield processed ullage by using the fluidic motive force; and

d) returning the processed ullage to the fuel tank by using the fluidic motive force.

2. A method as recited in claim 1, further comprising the step of removing heat from the processed ullage.

3. A method as recited in claim 1, wherein the fuel tank is a center wing tank of an airplane and further comprising the steps of using the ram air to cool the catalyst and the ullage and powering a pump with the ram air to create the fluidic motive force.

4. A method as recited in claim 1, further comprising the step of providing the removed ullage to a secondary catalytic unit to create heated ullage for the main catalytic unit, wherein the secondary catalytic unit is relatively smaller than the main catalytic unit.

5. A system for reducing reactive components in ullage of a fuel tank comprising:

an air driven unit for creating a fluidic motive force to remove ullage from the fuel tank;

a main catalytic unit for receiving the ullage and reducing the reactive components to yield processed ullage for return to the fuel tank;

a secondary catalytic unit to create heated ullage for the main catalytic unit, wherein the secondary catalytic unit is relatively smaller than the main catalytic unit; and

a secondary heat exchanger cooled by ram air;

wherein the fuel tank is a center wing tank of an airplane and airplane ram air is used to drive the air driven unit and cool the processed ullage.

6. A system as recited in claim 5, further comprising a heat exchanger for removing heat from the processed ullage.

7. A system as recited in claim 5, further comprising a flow control valve for controlling delivery of the airplane ram air to the air driven unit.

8. A system as recited in claim 6, wherein the fuel tank is a center wing tank of an airplane and airplane engine bleed air is used to pre-heat the main catalytic unit and further comprising a valve operative to selectively provide the airplane engine bleed air to the main catalytic unit.

9. A system as recited in claim 5, further comprising an orifice to restrict ullage flow to the secondary catalytic unit.

10. A method for reducing reactive components in ullage of a fuel tank, the method comprising the steps of:

a) using engine bleed air to create a fluidic motive force;

b) applying the fluidic motive force to the fuel tank to remove ullage;

c) providing the removed ullage to a main catalyst for reducing the reactive components to yield processed ullage;

d) returning the processed ullage to the fuel tank;

e) during ground operations, using engine bleed air to cool the catalyst and, in turn, the ullage; and

f) during flight, additionally using ram air to cool the catalyst and, in turn, the ullage.

11. A method as recited in claim 10, further comprising the step of removing heat from the processed ullage by passing ram air through at least one heat exchanger.

12. A method as recited in claim 10,

wherein the fuel tank is a center wing tank of an airplane.

13. A method as recited in claim 10, further comprising the step of providing the engine bleed air to an ejector venturi to create vacuum as the fluidic motive force.

14. A method as recited in claim 10, further comprising the step of providing the engine bleed air to the catalyst for pre-heating during initial operation.

15. A method as recited in claim 10, wherein steps c) and d) utilize the fluidic motive force.

16. A method as recited in claim 10, further comprising the step of varying the ullage flow based on temperature.