Method for reducing propellant curing residual stress by high-energy acoustic beam

Patent metadata

Field	Value
Publication number	US-11814331-B2
Application number	US-202016751731-A
Country	US
Kind code	B2
Filing date	Jan 24, 2020
Priority date	Jan 31, 2019
Publication date	Nov 14, 2023
Grant date	Nov 14, 2023

Abstract

The present disclosure is related to the technical field of propellant performance research, and in particular, to a method for reducing propellant curing residual stress by a high-energy acoustic beam. The method includes the following steps: injecting a propellant slurry into a curing container and waiting for the propellant slurry to start curing; actuating, when the propellant slurry starts curing, a high-energy acoustic beam generator and a high-energy acoustic beam transducer to continuously emit high-energy acoustic beam to the propellant slurry in the curing container until the propellant slurry is cured to form a propellant grain; and closing the high-energy acoustic beam generator and the high-energy acoustic beam transducer. The method for reducing propellant curing residual stress by high-energy acoustic beam provided in the present disclosure can reduce residual stress inside the propellant in an effective manner, thereby ensuring operation safety of the aerospace equipment.

First claim

What is claimed is:

1. A method for reducing propellant curing residual stress by a high-energy acoustic beam, comprising the following steps:
a step S 1 , in which a propellant slurry is injected into a curing container so as to wait for the propellant slurry to start curing;
a step S 2 , in which when the propellant slurry starts curing, a high-energy acoustic beam generator and a high-energy acoustic beam transducer are actuated to continuously emit a high-energy acoustic beam sensitive to stress and having a high-frequency and small-amplitude to the propellant slurry in the curing container to until the propellant slurry is cured to form a propellant grain, wherein the high-energy acoustic beam sensitive to stress and having high-frequency and small-amplitude makes particles of the propellant slurry more compact, improves a leveling property of a surface of the propellant slurry and facilitates escaping of air in the propellant slurry, so as to improve mechanical properties and stability of the propellant slurry, make the propellant slurry reduce or prevent forming of the internal residual stress, and eliminate the residual stress inside the propellant; and
a step S 3 , in which the high-energy acoustic beam generator and the high-energy acoustic beam transducer are closed.

2. The method as claimed in claim 1 , further comprising a step S 21 before or during the step S 2 , in which an operating frequency of the high-energy acoustic beam are adjusted based on a frequency of the high-energy acoustic beam transducer to ensure phases of an output voltage and an output current are consistent.

3. The method as claimed in claim 2 , further comprising adjusting the operating frequency of the high-energy acoustic beam based on a waveform change displayed by an oscilloscope in the step S 2 .

4. The method as claimed in claim 1 , further comprising a step S 22 before the step S 2 , in which a curing period of time is calculated based on a volume of the injected propellant slurry and a frequency of the high-energy acoustic beam transducer, a timing of a timing alarm device is set based on the calculated curing period of time, and the timing alarm device is actuated; and the step S 3 further comprising issuing, by the timing alarm device, any one or more of alarms of bell-ringing, flashing and the like after the propellant slurry is formed as the propellant grain.

5. The method as claimed in claim 4 , further comprising automatically closing, after a predetermined period of time since the timing alarm device issues any one of more of the alarms of the bell-ringing, the flashing and the like in the step S 3 , the high-energy acoustic beam transducer and the high-energy acoustic beam generator to stop working if the alarm(s) issued by the timing alarm device is not stopped.

6. The method as claimed in claim 1 , further comprising a step S 41 after the step S 3 , in which one of an upper separated part and a lower separated part of the curing container, which are connected to each other in a tight and sealed manner and separable up and down, is removed, and the propellant grain is taken out from the curing container.

7. The method as claimed in claim 1 , further comprising a step S 42 after the step S 3 , in which one of a left separated part or a right separated part of the curing container, which are connected to each other in a tight and sealed manner and separable left and right, is removed, and the propellant grain is taken out from the curing container.

8. The method as claimed in claim 6 , further comprising coating a layer of a release agent on an inner surface of the curing container before the step S 1 .

9. The method as claimed in claim 1 , further comprising a step S 0 before the step S 1 or the step S 2 , in which a coupling agent is evenly coated on a portion of the curing container with which the high-energy acoustic beam transducer contacts, and coupling of the curing container to the high-energy acoustic beam transducer is made.

Assignees

• Beijing Institute Tech

Inventors

• Xu Chunguang
• Yin Peng
• Lu Yuren
• Jia Ruili
• Song Jianfeng

Classifications

• C06B21/0091 Primary

  Elimination of undesirable or temporary components of an intermediate or finished product, e.g. making porous or low density products, purifying, stabilising, drying; Deactivating; Reclaiming; (porous inert particles or chemicals compounded for these purposes C06B23/00) · CPC title

• B29C35/08

  by wave energy or particle radiation {(B29C64/00, B29C71/04 take precedence)} · CPC title

• C06B21/0058

  by casting a curable composition, e.g. of the plastisol type · CPC title