2-pulse gas generator and method of measuring propellant combustion surface position

Patent metadata

Field	Value
Publication number	US-11326557-B2
Application number	US-201816204151-A
Country	US
Kind code	B2
Filing date	Nov 29, 2018
Priority date	Mar 30, 2018
Publication date	May 10, 2022
Grant date	May 10, 2022

Abstract

The first solid propellant is formed to have a columnar shape so as for a combustion surface to move to a first direction, and to have an end surface exposed to a combustion space. The surface of first solid propellant except for the end surface is covered with a barrier membrane. The position of combustion surface in the first direction is detected by a position sensor device in an always-on measurement or a fixed-point measurement. Based on the detected result, the consumption amount of the first solid propellant is estimated.

First claim

What is claimed is:

1. A 2-pulse gas generator comprising:
a pressure vessel provided with a combustion space therein;
a first solid propellant arranged inside the pressure vessel, wherein a first end surface of the first solid propellant is exposed to the combustion space;
a first igniter configured to ignite the first end surface of the first solid propellant;
a barrier membrane provided to cover a surface of the first solid propellant other than any combustion surface such that a combustion surface of the first solid propellant moves in a predetermined first direction as combustion of first solid propellant advances;
a position sensor device configured to detect a position of the combustion surface in the predetermined first direction; and
a processing device configured to estimate a consumption amount of the first solid propellant based on a detection result of the position of the combustion surface,
wherein the pressure vessel comprises:
a thruster section configured to exhaust out a combustion gas generated by the combustion of the first solid propellant from the pressure vessel through an area adjustable opening section; and
a pressure sensor device configured to measure a combustion pressure in the combustion space,
wherein the processing device calculates a setting value of the combustion pressure necessary to combust out the first solid propellant by a desired time based on the detection result of the position of the combustion surface and a measurement result of the combustion pressure,
wherein the 2-pulse gas generator further comprises:
a control device configured to adjust the combustion pressure based on the setting value by adjusting an area of the opening section of the thruster section;
a second solid propellant arranged inside the pressure vessel; and
a second igniter configured to ignite the second solid propellant at the desired time,
wherein the position sensor device detects the position of the combustion surface in the predetermined first direction at a timing controlled by the control device,
wherein the position sensor device comprises another pressure sensor device which is a high response pressure sensor arranged to oppose the combustion surface across the combustion space and configured to measure the combustion pressure, and
wherein the processing device analyzes frequency components of the combustion pressure measured by the high response pressure sensor, and calculates a distance from the high response pressure sensor to the combustion surface based on a frequency component having the maximum amplitude of the frequency components.

2. The 2-pulse gas generator according to claim 1 , wherein the position sensor device comprises:
an ultrasonic sensor arranged inside the first solid propellant to oppose the combustion surface, and configured to detect the position of the combustion surface in the predetermined first direction by measuring a distance to the combustion surface.

3. The 2-pulse gas generator according to claim 1 , further comprising:
a temperature measurement device configured to measure a temperature of the first solid propellant and the combustion gas.

4. The 2-pulse gas generator according to claim 1 , wherein the position sensor device detects that the combustion surface has reached a predetermined position in the predetermined first direction when the combustion surface has reached the predetermined position in the predetermined first direction.

5. The 2-pulse gas generator according to claim 4 , wherein the position sensor device comprises a temperature detector configured to measure a temperature of the predetermined position inside the first solid propellant.

6. The 2-pulse gas generator according to claim 4 , wherein the position sensor device comprises:
an optical fiber embedded inside the first solid propellant and having one end arranged at the predetermined position; and
a photo-coupler optically connected with an other end of the optical fiber, and configured to detect a light of the combustion gas through the optical fiber when the combustion of the first solid propellant advances so that the combustion surface has reached the predetermined position, and to generate a detection signal based on detection of the light by the photo-coupler to transmit to the processing device.

7. The 2-pulse gas generator according to claim 4 , wherein the position sensor device comprises a nichrome wire embedded inside the first solid propellant and having ends electrically connected with the processing device,
wherein a part of the nichrome wire which is near the first end surface in the predetermined first direction is arranged at the predetermined position, and
wherein the processing device detects that the nichrome wire has broken, to detect that the combustion surface has reached the predetermined position.

8. The 2-pulse gas generator according to claim 6 , further comprising:
a temperature measurement device configured to measure a temperature of the first solid propellant and the combustion gas.

9. A 2-pulse gas generator comprising:
a pressure vessel provided with a combustion space therein;
a first solid propellant arranged inside the pressure vessel, wherein a first end surface of the first solid propellant is exposed to the combustion space:
a first igniter configured to ignite the first end surface of the first solid propellant:
a barrier membrane provided to cover a surface of the first solid propellant other than any combustion surface such that a combustion surface of the first solid propellant moves in a predetermined first direction as combustion of first solid propellant advances,
a position sensor device configured to detect a position of the combustion surface in the predetermined first direction; and
a processing device configured to estimate a consumption amount of the first solid propellant based on a detection result of the position of the combustion surface,
wherein the pressure vessel comprises:
a thruster section configured to exhaust out a combustion gas generated by the combustion of the first solid propellant from the pressure vessel through an area adjustable opening section; and
a pressure sensor device configured to measure a combustion pressure in the combustion space,
wherein the processing device calculates a setting value of the combustion pressure necessary to combust out the first solid propellant by a desired time based on the detection result of the position of the combustion surface and a measurement result of the combustion pressure,
wherein the 2-pulse gas generator further comprises:
a control device configured to adjust the combustion pressure based on the setting value by adjusting an area of the opening section of the thruster section;
a second solid propellant arranged inside the pressure vessel; and
a second igniter configured to ignite the second solid propellant at the desired time,
wherein the position sensor device detects the position of the combustion surface in the predetermined first direction at a timing controlled by the control device,
wherein the pressure sensor device is arranged to oppose the combustion surface across the combustion space, and configured to function as the position sensor device which measures the combustion pressure, and
wherein the processing device analyzes frequency components of the combustion pressure measured by the pressure sensor device, and calculates a distance from the pressure sensor device to the combustion surface based on a frequency component having the maximum amplitude of the frequency components.

10. The 2-pulse gas generator according to claim 9 , further comprising:
a temperature measurement device configured to measure a t

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Nishikawa Seiki
• Mihara Chiyako
• Suzuki Tasuku
• Ieki Katsunori

Classifications

• F02K9/96

  characterised by specially adapted arrangements for testing or measuring · CPC title

• F02K9/94

  Re-ignitable or restartable rocket- engine plants; Intermittently operated rocket-engine plants · CPC title

• F02K9/12 Primary

  made of two or more portions burning at different rates {or having different characteristics} · CPC title

• F02K9/28

  having two or more propellant charges with the propulsion gases exhausting through a common nozzle · CPC title

• F02K9/95 Primary

  characterised by starting or ignition means or arrangements (safety devices F02K9/38) · CPC title