阅读说明：本技术 双基系推进剂不同过载方向燃烧的测试发动机及测试方法 (Test engine and test method for combustion of double-base propellant in different overload directions ) 是由 李猛 赵凤起 李军伟 张智慧 许云志 李武 徐司雨 李恒 裴庆 姚二岗 姜菡雨 于 2019-10-14 设计创作，主要内容包括：本发明公开了一种双基系推进剂不同过载方向燃烧的测试发动机及测试方法,成功解决了过载方向对推进剂燃烧的影响。本发明燃烧室壳体设有爆破装置,爆破装置上安装大小双圆台阶状爆破密封塞,并用爆破盖拧紧；燃烧室壳体中部设有喷管,高强度石墨安装于喷管座中,并用压盖拧紧以防止试验中石墨喷喉喷出。燃烧室壳体以喷管中心为对称轴,一边放置端面燃烧推进剂装药、一边放置假药柱,通过互换推进剂装药与假药柱的位置,达到改变过载方向的目的。为避免过载下装药燃烧堵塞喷管及点火药甩出,采用燃烧后无残渣的赛璐珞盒固定点火药,保障过载下发动机试验的安全性和可靠性。适用于不同过载方向下推进剂装药燃烧特性和内弹道性能的测量及评价。(The invention discloses a test engine and a test method for combustion of a double-base propellant in different overload directions, which successfully solve the influence of the overload directions on the combustion of the propellant. The combustion chamber shell is provided with a blasting device, wherein a large and small double-truncated-cone step-shaped blasting sealing plug is arranged on the blasting device and is screwed down by a blasting cover; the middle part of the combustion chamber shell is provided with a spray pipe, and the high-strength graphite is arranged in a spray pipe seat and is screwed by a gland to prevent the graphite spray throat from spraying out in the test. The combustion chamber shell uses the center of the spray pipe as a symmetry axis, the end face combustion propellant charge is placed while the fake explosive column is placed, and the overload direction is changed by interchanging the positions of the propellant charge and the fake explosive column. In order to avoid blocking the spray pipe by charging combustion and throwing out ignition powder under overload, the celluloid box without residue after combustion is adopted to fix the ignition powder, thereby ensuring the safety and reliability of the engine test under overload. The method is suitable for measuring and evaluating the combustion characteristics and the internal ballistic performance of the propellant charge in different overload directions.)

1. A test engine for combustion of double-base propellant in different overload directions is characterized in that: the device comprises a combustion chamber shell (1), a front seal head (2), a sealing rubber ring (3), a cushion block (4), a blasting device (5), a pressure sensor base (6), a propellant charge (7), a spray pipe (8), an ignition medicine box (9), a fake medicine column (10) and a rear seal head (11);

the combustion chamber shell (1) is cylindrical, two ends of the combustion chamber shell are respectively connected with the front seal head (2) and the rear seal head (11) through threads, the front seal head (2) and the rear seal head (11) are consistent in size and structure, and the front seal head (2) and the rear seal head are sealed with the combustion chamber shell (1) through the sealing rubber ring (3); the middle part of the combustion chamber shell (1) is provided with a spray pipe (8), the combustion chamber shell (1) takes the central axis of the spray pipe (8) as a symmetry axis, a cushion block (4) and an end face combustion propellant charge (7) are arranged on one side of the combustion chamber shell, a fake explosive column (10) is arranged on the other side of the combustion chamber shell, the combustion chamber shell is separated by an ignition medicine box (9), and the overload direction can be changed by interchanging the positions of the cushion block (4), the end face combustion propellant charge (7) and the fake explosive column (10); one end of the end face combustion propellant charge (7) is a ball head and is in contact with the buffer cushion block (4), and the other end of the end face combustion propellant charge is provided with a circular conical groove and is in contact with an ignition medicine box (9);

the middle part of the combustion chamber shell (1) is also provided with a pressure sensor base (6) and a blasting device (5), the spray pipe (8), the blasting device (5) and the pressure sensor base (6) are positioned on a radial middle surface, and an included angle among the axes of the spray pipe (8), the blasting device (5) and the pressure sensor base (6) is 75 degrees, so that the test engine can be conveniently installed on a rotary overload test bed;

the detachable pressure sensor is in threaded connection with the pressure sensor base (6).

2. A test engine for combustion of a dual prime propellant in different directions of overload according to claim 1 wherein: the blasting device (5) comprises a blasting device base (5-1), a blasting sealing plug (5-2) and a blasting cover (5-3), wherein the blasting sealing plug (5-2) is installed on the blasting device base (5-1), the blasting sealing plug (5-2) is in a large and small double-truncated-cone step shape, silicon rubber is coated around the small round end of the blasting sealing plug (5-2), the blasting sealing plug is installed in the blasting cover (5-3), Ethylene Propylene Diene Monomer (EPDM) heat insulating materials are coated on the large round end of the blasting sealing plug (5-2), and the blasting cover (5-3) with the blasting sealing plug (5-2) is screwed into the blasting device base (5-1) to be fastened.

3. A test engine for combustion of a dual prime propellant in different directions of overload according to claim 1 wherein: the spray pipe (8) comprises a spray pipe seat (8-1), high-strength graphite (8-2) and a spray pipe gland (8-3), wherein the high-strength graphite (8-2) is installed in the spray pipe seat (8-1) and is compressed by the spray pipe gland (8-3) to prevent the high-strength graphite from being sprayed out from the spray pipe throat (8-2) and influence the normal combustion of propellant charge and the measurement of combustion characteristic parameters.

4. A test engine for combustion of a dual prime propellant in different directions of overload according to claim 1 wherein: the ignition medicine box (9) comprises an ignition medicine box main body (9-2) and an ignition medicine box end cover (9-1), an ignition line hole (9-3) is formed in the side face of the ignition medicine box main body (9-2), weighed ignition medicine and an ignition head are bound into an ignition medicine bag which is filled into the ignition medicine box main body (9-2), an ignition line penetrates out of the ignition line hole (9-3), the ignition medicine box end cover (9-1) is covered, and the ignition line penetrates out of the spray pipe (8) through the cooperation of a lead.

5. The test engine for combustion of a dual prime mover in different directions of overload as claimed in claim 4 wherein: the ignition medicine box main body (9-2) is formed by die pressing celluloid.

6. The test engine for combustion of a dual-base propellant in different overload directions according to claim 3, wherein: the blasting threshold value of the blasting device (5) is 20MPa, the requirement of double-base system propellant charge combustion pressure is met, the thread pressure bearing capacity of the nozzle gland (8-3) is greater than 30MPa and less than 35MPa, the pressure bearing capacity of the combustion chamber shell (1) is greater than or equal to 40MPa, and the pressure relief sequence of the blasting device (5), the nozzle gland (8-3) and the combustion chamber shell (1) is as follows.

7. The test engine for combustion of a dual-base propellant in different overload directions according to claim 2, wherein: and an ethylene propylene diene monomer thermal insulation material is coated on the end, close to the combustion chamber, of the blasting sealing plug (5-2).

8. A test method for combustion of a double-base propellant in different overload directions is characterized by comprising the following steps: the method comprises the following steps:

1) preparing a double-base propellant grain, shaping and turning the grain, and coating the grain by an ethylene propylene diene monomer coating technology to prepare end face combustion propellant charge;

2) calculating the dosage of the ignition powder according to the propellant charge size and the free volume of the combustion chamber;

3) testing engine assembly: firstly, putting a combustion chamber shell into a vice for fixing, putting a fake explosive column into the front end of the combustion chamber, sleeving a sealing ring on the front cover thread, and screwing the front cover into the combustion chamber shell for fastening; the weighed ignition explosive charges are loaded into an ignition medicine box, an ignition wire penetrates out of the ignition medicine box from an ignition wire hole on the side surface, and the ignition wire penetrates out of the spray pipe by matching of a lead; the propellant charge conical groove faces forwards and the ball head faces backwards, the propellant charge conical groove is slowly sent into the combustion chamber shell, the cushion block is placed at the position of the charge ball head in the combustion chamber shell, the rear cover is sleeved with the sealing ring and screwed into the combustion chamber shell for fastening; screwing the calibrated pressure sensor into a pressure sensor base, and marking the position of the charged powder on the combustion chamber shell;

4) according to the rotating speed n and the overload a of the rotating overload test bed_nCorresponding relation a between_n＝ω²r＝(2πn)²r＝4π²r·n²The distance r between the central axis of the rotary overload test bed and the center of mass of the test engine is 0.726m, and the corresponding relation between the overload value of the test engine and the rotating speed of the rotary overload test bed is obtained as follows:

5) fixing the assembled test engine on a measurement bench of a rotary overload test bed, and enabling one end of the marked charge to face the rotary overload test bed or to face a position far away from the shaft so as to achieve the purpose of changing the overload direction of the charge in the rotating process; connecting the calibrated pressure measuring sensor and the ignition wire;

6) starting a motor to rotate, setting the rotating speed of a rotary overload test bed according to the requirement of the overload value of the test engine, igniting propellant charge when the rotating speed of the rotary overload test bed is stable and meets the requirement, starting the test engine to work, starting a synchronous trigger system, and collecting pressure measurement data;

7) and (3) carrying out data processing on the pressure measurement data, so that the influence of different overload directions on the internal trajectory characteristic and the dynamic burning rate characteristic of the double-base system propellant charge can be tested.

9. The method for testing the combustion of the modified biradical propellant system in different overload directions as claimed in claim 8, wherein the method comprises the following steps: the fourth step further comprises: before the test, the rotating overload test bed is checked and debugged to ensure reliable operation; the ignition system and the combustion chamber pressure test parameters under the rotation overload state are jointly tested, the ignition can be simultaneously carried out under the rotation overload state, and the combustion chamber pressure data acquisition is carried out.

10. The method for testing the combustion of the modified biradical propellant system in different overload directions as claimed in claim 8, wherein the method comprises the following steps: in the sixth step, the acquisition speed is 1000 points/second.

Technical Field

The invention relates to a test engine and a test method for combustion of a double-base propellant in different overload directions, which are suitable for the technical field of evaluation and characterization of the charge rotation overload combustion characteristics of a solid propellant.

Background

The high precision, high speed, and high penetration of the weapon systems in modern war become the determining factors for success and failure of missions. Such as high-speed ground-air reverse guided missiles, air-air missiles, gun-launched missiles and the like, can generate larger flight overload and transverse overload in the processes of high acceleration, strong maneuvering flight or sharp turning. The overload environment influences the charge combustion and the internal flow field of the solid rocket engine, so that the combustion speed of the propellant is increased, the pressure of a combustion chamber is increased, the working time is shortened, the flow rule of charge combustion products is influenced, and the internal ballistic performance of the engine and the external ballistic performance of the missile are further influenced; the overload environment worsens the ablation environment of the coating of the explosive package, and leads to the failure of the protection of the coating when the overload environment is serious, and the engine burns through and disintegrates.

According to literature reports, many cases that the normal work of propellant charges is influenced by high overload in foreign countries to cause the failure of projectile weapon equipment are reported, and on the background, a large number of researches such as the design of the drug type, the formula design, the internal ballistic performance tests under static and overload conditions, the numerical simulation and the like of the propellant charges under the overload condition are developed to deeply understand the combustion rule and mechanism of the propellant charges under the overload condition. The research shows that: the direction of the overload relative to the combustion surface has a great influence on the combustion speed of the propellant, so that the combustion of the charge is influenced, and the inner ballistic performance is abnormal. There is therefore a great need to develop research into the combustion characteristics of propellant charges in different overload directions.

Disclosure of Invention

In order to solve the defects of the prior art, the invention provides the test engine and the test method for the combustion of the double-base propellant in different overload directions, the test engine and the test method can be used for testing, evaluating and representing the combustion characteristics and the internal ballistic characteristics of the propellant in different overload directions, the threat of propellant charge combustion to a rotary overload test platform under an overload condition is weakened, and the safety of the engine test under the overload condition is improved.

A test engine for combustion of a double-base system propellant in different overload directions comprises a combustion chamber shell, a front seal head, a sealing rubber ring, a cushion block, a blasting device, a pressure sensor base, propellant charge, a spray pipe, an ignition medicine box, a fake explosive column and a rear seal head;

the combustion chamber shell is cylindrical, two ends of the combustion chamber shell are respectively connected with the front end enclosure and the rear end enclosure through threads, the size and the structure of the front end enclosure and the size and the structure of the rear end enclosure are consistent, and the front end enclosure and the rear end enclosure are sealed with the combustion chamber shell through sealing rubber rings; the middle part of the combustion chamber shell is provided with a spray pipe, the combustion chamber shell takes the central axis of the spray pipe as a symmetry axis, a cushion block and an end face combustion propellant charge are placed on the combustion chamber shell, a fake explosive column prepared from bakelite is placed on the combustion chamber shell, the spray pipe is arranged in the middle part of the combustion chamber shell, and the purpose of changing the overload direction is achieved by interchanging the positions of the cushion block and the end face combustion propellant charge with the fake explosive column; one end of the cylindrical end face combustion propellant charge is a ball head and is in contact with the buffer cushion block, and the other end of the cylindrical end face combustion propellant charge is provided with an annular conical groove and is in contact with the ignition medicine box;

the middle part of the combustion chamber shell is also provided with a pressure sensor base and a blasting device, the spray pipe, the blasting device and the pressure sensor base are positioned on a radial middle surface, and the included angle among the axes of the spray pipe, the blasting device and the pressure sensor base is 75 degrees, so that the test engine can be conveniently installed on a rotary overload test bed;

the detachable pressure sensor is in threaded connection with the pressure sensor base.

Further, the blasting device comprises a blasting device base, a blasting sealing plug and a blasting cover, wherein the blasting sealing plug is installed on the blasting device base, the blasting sealing plug is in a large and small double-circular-table step shape, silicon rubber is coated on the periphery of the small circular end of the blasting sealing plug, the blasting sealing plug is installed in the blasting cover, Ethylene Propylene Diene Monomer (EPDM) heat-insulating material is coated on the large circular end of the blasting sealing plug, and the blasting cover with the blasting sealing plug is screwed into the blasting device base to be fastened.

Further, the spray pipe comprises a spray pipe seat, high-strength graphite and a spray pipe gland, wherein the high-strength graphite is arranged in the spray pipe seat and is compressed by the spray pipe gland to prevent the high-strength graphite from being sprayed out from the spray pipe throat, and the normal combustion of propellant charging and the measurement of combustion characteristic parameters are influenced.

Further, the ignition medicine box includes ignition medicine box main part and ignition medicine box end cover, and ignition medicine box main part side is equipped with the ignition line hole, wraps the ignition cartridge bag into with the some duration and degree of heating head that will weigh and packs into in the ignition medicine box main part to wear out the ignition line from the ignition line hole, cover the ignition medicine box end cover, wear out the spray tube with the ignition line with the lead wire cooperation.

Further, the ignition medicine box main body is formed by die-molding celluloid.

Furthermore, the blasting threshold value of the blasting device is 20MPa, the requirement of combustion pressure of double-base system propellant charge is met, the thread pressure bearing capacity of the nozzle gland is greater than 30MPa and less than 35MPa, the pressure bearing capacity of the combustion chamber shell is greater than or equal to 40MPa, and the pressure relief sequence of the blasting device, the nozzle gland and the combustion chamber shell is.

Furthermore, an ethylene-propylene-diene monomer thermal insulation material is coated on the end, close to the combustion chamber, of the explosion sealing plug.

A test method for combustion of a double-base propellant in different overload directions comprises the following steps:

1) preparing a double-base propellant grain, shaping and turning the grain, and coating the grain by an ethylene propylene diene monomer coating technology to prepare end face combustion propellant charge;

2) calculating the dosage of the ignition powder according to the propellant charge size and the free volume of the combustion chamber;

3) testing engine assembly: firstly, putting a combustion chamber shell into a vice for fixing, putting a fake explosive column into the front end of the combustion chamber, sleeving a sealing ring on the front cover thread, and screwing the front cover into the combustion chamber shell for fastening; the weighed ignition explosive charges are loaded into an ignition medicine box, an ignition wire penetrates out of the ignition medicine box from an ignition wire hole on the side surface, and the ignition wire penetrates out of the spray pipe by matching of a lead; the propellant charge conical groove faces forwards and the ball head faces backwards, the propellant charge conical groove is slowly sent into the combustion chamber shell, the cushion block is placed at the position of the charge ball head in the combustion chamber shell, the rear cover is sleeved with the sealing ring and screwed into the combustion chamber shell for fastening; screwing the calibrated pressure sensor into a pressure sensor base, and marking the position of the charged powder on the combustion chamber shell;

4) according to the rotating speed n and the overload a of the rotating overload test bed_nCorresponding relation a between_n＝ω²r＝(2πn)²r＝4π²r·n²The distance r between the central axis of the rotary overload test bed and the center of mass of the test engine is 0.726m, and the corresponding relation between the overload value of the test engine and the rotating speed of the rotary overload test bed is obtained as follows:

5) fixing the assembled test engine on a measurement bench of a rotary overload test bed, and enabling one end of the marked charge to face the rotary overload test bed or to face a position far away from the shaft so as to achieve the purpose of changing the overload direction of the charge in the rotating process; connecting the calibrated pressure measuring sensor and the ignition wire;

6) starting a motor to rotate, setting the rotating speed of a rotary overload test bed according to the requirement of the overload value of the test engine, igniting propellant charge when the rotating speed of the rotary overload test bed is stable and meets the requirement, starting the test engine to work, starting a synchronous trigger system, and collecting pressure measurement data;

7) and (3) carrying out data processing on the pressure measurement data, so that the influence of different overload directions on the internal trajectory characteristic and the dynamic burning rate characteristic of the double-base system propellant charge can be tested.

Further, the fourth step further includes: before the test, the rotating overload test bed is checked and debugged to ensure reliable operation; the ignition system and the combustion chamber pressure test parameters under the rotation overload state are jointly tested, the ignition can be simultaneously carried out under the rotation overload state, and the combustion chamber pressure data acquisition is carried out.

Further, in the sixth step, the acquisition speed is 1000 points/second.

The invention has the advantages that:

1. according to the invention, the spray pipe is arranged in the middle of the combustion chamber shell, the test engine structure takes the central axis of the spray pipe as a symmetry axis, one side of the symmetry axis is provided with the cushion block and the end face combustion propellant charge, and the other side of the symmetry axis is provided with the fake powder column prepared from bakelite; compared with the existing testing device and method, the overload angle of 0-90 degrees can be tested only, and the progress is obvious;

2. according to the invention, the spray pipe, the blasting device and the pressure sensor base are arranged in the middle of the combustion chamber shell, the three parts are positioned on the same radial plane, and the included angle among the axes of the spray pipe, the pressure relief hole and the pressure measuring hole is 75 degrees, so that the test engine can be conveniently mounted on a rotary overload test bed;

3. the celluloid box body is used for loading the ignition explosive package, so that the ignition explosive package is fixed, and the ignition explosive is prevented from being thrown out or leaking; no residue is left after the celluloid is combusted, so that the influences of blockage of a spray pipe by metal medicine box combustion residue, participation of metal in propellant combustion and the like are avoided;

4. according to the invention, the blasting device is arranged on the middle surface of the middle part, the blasting sealing plug is arranged on the blasting device, the blasting sealing plug is in a large-small double-truncated-cone step shape, the blasting threshold value of the sealing plug is 20MPa, and the safety and reliability of the test are improved on the premise of ensuring the research on the rotating overload combustion characteristic of the double-base-system propellant charge.

Drawings

FIG. 1 is a schematic view of the structure of the present invention. The device comprises a combustion chamber shell, a front seal head, a sealing rubber ring, a cushion block, a blasting device, a pressure sensor base, a propellant charge, a spray pipe, an ignition medicine box, a fake powder column and a rear seal head, wherein the combustion chamber shell comprises 1 part, 2 parts, the front seal head comprises 3 parts, the sealing rubber ring comprises 4 parts, the blasting device comprises 5 parts, the pressure sensor base comprises 6 parts, the propellant charge comprises 7 parts, the spray pipe comprises 8 parts.

Figure 2 is a schematic diagram of a dual-based propellant charge.

FIG. 3 is a schematic view of a blasting apparatus; wherein 5-1 is the base of the blasting device, 5-2 is the blasting sealing plug, and 5-3 is the blasting cover.

FIG. 4 is a schematic view of a nozzle; wherein 8-1 is a nozzle seat, 8-2 is high-strength graphite, and 8-3 is a nozzle gland.

FIG. 5 is a schematic view of an ignition cartridge; wherein, 9-1 is an ignition medicine box end cover, 9-2 is an ignition medicine box main body, and 9-3 is an ignition wire hole.

Figure 6 is a diagram of the propellant charge being placed close to the over-carrier axis.

Figure 7 is a diagram of the propellant charge positioned away from the axis of the overpower.

Detailed Description

The invention is further described below with reference to the figures and the specific embodiments.