Hypergolic hybrid motor igniter

• US 9,273,635 B2
• Filed: 03/29/2012
• Issued: 03/01/2016
• Est. Priority Date: 03/29/2012
• Status: Active Grant

• Current Assignee: Aerospace Corporation
• Original Assignee: Aerospace Corporation
• Inventors: Brady, Brian Blaise, DeSain, John D
• Primary Examiner(s): Wongwian, Phutthiwat
• Assistant Examiner(s): Rivera, Carlos A
• Application Number:
  US13/434,223
• Publication Number:
  US 20130255223A1
• Time in Patent Office: 1,433 Days
• US Class Current: 1/1
• CPC Class Codes: F02K 9/72 using liquid and solid propellants, i.e. hybrid rocket-engine plants

Abstract

An apparatus for igniting a larger rocket motor is provided. The apparatus may be a smaller rocket motor that can be ignited hypergolically, when a pressurized oxidizer contacts hypergolic fuel grains of the smaller rocket motor. The hypergolic ignition causes the larger rocket motor to be ignited. The hypergolic ignition of the smaller rocket motor may be stopped after the larger rocket motor is ignited, and the remaining hypergolic fuel grains and the pressurized oxidizer can be reserved for reigniting the larger rocket motor at a later time.

Claims

1. An apparatus, comprising:

hypergolic fuel grains configured to form a chamber coupled to a first inlet of a pre-combustion chamber of a larger rocket motor;

an oxidizer valve configured to allow a pressurized oxidizer to enter the chamber, and upon contact with the hypergolic fuel grains, burn the hypergolic fuel grains to generate a flame in the pre-combustion chamber; and

an injector configured to inject the pressurized oxidizer through a second inlet of the pre-combustion chamber;

wherein

the hypergolic fuel grains are configured to cause an ignition of the larger rocket motor upon contact with the pressurized oxidizer by mixing the flame with the pressurized oxidizer injected by the injector through the second inlet, and

when the oxidizer valve is closed, the pressurized oxidizer is prevented from entering the chamber and the hypergolic fuel grains are extinguished from burning.

2. The apparatus of claim 1, wherein the hypergolic fuel grains comprise paraffin wax, low-density polyethylene, or both.

3. The apparatus of claim 2, wherein the paraffin wax, the low density polyethylene, or both, comprise one or more of lithium aluminum hydride or metal hydrides, triethyl aluminum, disobutyl aluminum hydride, sodium bis aluminum hydride, or triethyl borane.

4. The apparatus of claim 1, wherein the pressurized oxidizer comprises one or more of nitric acid, hydrochloric acid, sulfuric acid, red fuming nitric acid, hydrogen peroxide or inhibited red fuming nitric acid.

5. The apparatus of claim 1, wherein, when the oxidizer valve is closed, a flow of the pressurized oxidizer is prevented from entering the chamber such that the hypergolic fuel grains are prevented from producing the flame to ignite the larger rocket motor.

6. The apparatus of claim 1, wherein, when the oxidizer valve is opened during initial operation or during subsequent operation of the apparatus, the pressurized oxidizer flows into the chamber and the hypergolic fuel grains are further configured to produce, upon contact with the pressurized oxidizer, the flame to ignite or reignite the larger rocket motor.

7. An apparatus, comprising:

a first rocket motor comprising hypergolic fuel grains configured to receive a pressurized oxidizer and coupled to a first inlet of a pre-combustion chamber of a second rocket motor; and

an injector configured to inject the pressurized oxidizer through a second inlet of the pre-combustion chamber, wherein

the first rocket motor is configured to ignite, and reignite at a later time, the second rocket motor by generating a flame in the re-combustion chamber and by mixing the flame with the pressurized oxidizer injected by the injector through the second inlet, and

the flame is generated when the hypergolic fuel grains burn upon contact with the received pressurized oxidizer, and extinguish from burning when the pressurized oxidizer is prevented from contacting the hypergolic fuel grains.

8. The apparatus of claim 7, wherein the first rocket motor further comprises a valve.

9. The apparatus of claim 8, wherein, when the valve is opened, a pressurized oxidizer enters a chamber formed by the hypergolic fuel grains.

10. The apparatus of claim 9, wherein the hypergolic fuel grains are configured to generate the flame to ignite the second rocket motor when the pressurized oxidizer contacts the hypergolic fuel grains.

11. The apparatus of claim 10, wherein, when the valve is closed, the pressurized oxidizer is prevented from contacting the hypergolic fuel grains such that the flame of the first rocket motor is extinguished.

12. A hybrid rocket motor, comprising:

hypergolic fuel grains configured to form a first chamber configured to receive pressurized oxidizer and connected to a first inlet of a pre-combustion chamber of a larger rocket motor; and

an injector configured to inject the pressurized oxidizer through a second net of the pre-combustion chamber,

wherein the hypergolic fuel grains are configured to ignite the larger rocket motor when the pressurized oxidizer is released into the first chamber formed by the hypergolic fuel grains to generate a flame in the pre-combustion chamber and by mixing the flame with the pressurized oxidizer injected by the injector through the second inlet, and

the hypergolic fuel grains are extinguished from burning when the pressurized oxidizer is prevented from being released into the first chamber formed by the hypergolic fuel grains.

13. The apparatus of claim 12, further comprising:

pressurized oxidizer storage comprising the pressurized oxidizer,

wherein the pressurized oxidizer comprises one or more of nitric acid, hydrochloric acid, sulfuric acid, red fuming nitric acid, or inhibited red fuming nitric acid.

14. The apparatus of claim 12, further comprising:

a valve configured to allow the pressurized oxidizer to be released into the first chamber.

15. The apparatus of claim 14, wherein, when the valve is open, the pressurized oxidizer is released into the first chamber, and upon contact with the hypergolic fuel grains, the hypergolic fuel grains produce the flame in the pre-combustion chamber of the larger rocket motor to ignite the larger rocket motor.

16. The apparatus of claim 15, wherein, when the valve is closed after a predetermined period of time, the pressurized oxidizer is prevented from contacting the hypergolic fuel grains such that the flame is extinguished.

17. The apparatus of claim 12, wherein the hypergolic fuel grains comprise paraffin wax comprising one or more of the following:

lithium aluminum hydride or metal hydrides, triethyl aluminum, disobutyl aluminum hydride, sodium bis aluminum hydride, and triethyl borane.

18. The apparatus of claim 12, wherein the hypergolic fuel grains comprise low density polyethylene with one or more of the following:

lithium aluminum hydride or metal hydrides, triethyl aluminum, disobutyl aluminum hydride, sodium bis aluminum hydride, and triethyl borane.