Compact-structure solid fuel ramjet with air inlet in middle

Abstract

The invention provides a solid fuel ramjet engine with a compact structure and with air entering from the middle, the engine sequentially comprises a center cone, connecting plates, an air inlet channel, a charging combustion chamber, an afterburning chamber and a spray pipe from front to back, the center cone and the air inlet channel are arranged in a segmented mode in the axial direction, and the center cone and the air inlet channel are connected through a plurality of connecting plates which are evenly arranged in the circumferential direction. The center cone and the air inlet channel are axially designed in a segmented mode, the size of the center cone and the flow area of the air inlet channel are decoupled, the length of the engine is greatly shortened, and the space utilization rate is increased.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solid fuel ramjet, and particularly relates to a compact middle air inlet solid fuel ramjet. BACKGROUND

[0002] The solid fuel ramjet is generally applied to range increasing shells, and is generally of an axisymmetric structure to adapt to the launching of a gun barrel. Figure 1 As shown in the figure, the conventional solid fuel ramjet comprises, from front to back, an air inlet, a charge combustion chamber, a supplementary combustion chamber and a nozzle, the air inlet adopts head air inlet, the captured air flows through the annular flow channel of the center cone and the shell, enters the charge combustion chamber, and the center cone is generally arranged with a warhead and a control system.

[0003] The center cone and the air inlet flow channel of the conventional solid fuel ramjet are of a parallel layout, the total cross-sectional area of the air inlet and the center cone is limited by the maximum cross section of the engine, the smaller the air inlet flow channel is, the faster the flow velocity is, and the greater the flow loss is, so the cross-sectional area of the air inlet flow channel cannot be too small. In order to ensure that there is enough space to arrange the warhead and the control system in the center cone, the length of the center cone needs to be increased, and the air inlet flow channel is also relatively long. The long-distance flow of the air flow in the air inlet will lead to an increase in flow loss, and at the same time, space is wasted, so that a compact layout cannot be achieved, which is not conducive to improving the performance of the engine. SUMMARY

[0004] In view of the above technical problems, the application provides a compact middle air inlet solid fuel ramjet, the center cone and the air inlet are designed in a segmented manner along the axial direction, the size of the center cone is decoupled from the flow area of the air inlet, the length of the engine is greatly shortened, and the space utilization is improved.

[0005] The technical scheme adopted by the application to solve the above technical problems is as follows:

[0006] The application provides a compact middle air inlet solid fuel ramjet, the engine comprises, from front to back, a center cone, a connecting plate, an air inlet, a charge combustion chamber, a supplementary combustion chamber and a nozzle, the center cone and the air inlet are arranged in a segmented manner along the axial direction, and the center cone and the air inlet are connected through a plurality of connecting plates arranged in a uniform manner in the circumferential direction.

[0007] Further, the connecting plates are 3 or 4, and are arranged in a central symmetry around the engine axis.

[0008] Further, the connecting plates are rib plates, the connecting plates have a sweepback angle of not less than 60°, and the connecting plates are provided with a backward inclined angle in front of and behind the air flow direction.

[0009] Further, under the condition of meeting the load strength requirement, the size of the connecting plate is the smallest.

[0010] Further, the center cone rear section part extends into the air inlet channel.

[0011] Further, the center cone rear section adopts a streamline design.

[0012] Further, the connecting plate windward position is processed with a plurality of holes, and the holes are communicated to the opening on the air inlet channel shell to form a suction channel.

[0013] Further, the center cone, air inlet channel and connecting plate are integrally formed by 3D printing.

[0014] Further, the middle air inlet solid fuel ramjet engine is applied to a range increasing shell.

[0015] The beneficial effects of the present application compared with the prior art are:

[0016] 1, the center cone and the air inlet channel are axially segmented

[0017] The present application proposes a center cone and air inlet channel axial segmentation design method, the length of the center cone and the air inlet channel can be greatly shortened, the connecting plate is used to connect the center cone and the air inlet channel, the space utilization is improved, and the problems of too long air inlet channel and low engine space utilization caused by parallel layout of the air inlet channel and the center cone are solved.

[0018] 2, the center cone rear section profile is easy to realize low resistance design

[0019] The existing solid rocket ramjet engine arranges the gas generator in the center cone, and there is a strict size constraint in the center cone rear section, so that the center cone rear section profile cannot realize low resistance design, and the flow loss is large. The solid fuel ramjet engine of the present application arranges the charge after the air inlet channel, completely decouples the center cone, air inlet channel and charge combustion chamber structure, and the center cone rear section profile is easy to realize low resistance design. Further, the center cone rear section of the present application adopts a slowly changing low resistance profile, which can minimize the loss and improve the engine performance.

[0020] 3, using suction of low energy flow to improve engine performance

[0021] The present application uses the static pressure of low energy flow which is higher than the ambient pressure, sets a plurality of holes at the windward position of the connecting plate, and the low energy flow flows through the connecting plate and the air inlet channel shell to be discharged to the outside of the engine, so as to improve the engine performance by suction. BRIEF DESCRIPTION OF DRAWINGS

[0022] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is readily understood that the drawings are merely illustrative of some embodiments of the application and therefore are not to be construed as limiting the scope of the application.

[0023] Figure 1 Fig. 1 is a structural schematic diagram of a prior art solid fuel ramjet engine;

[0024] Figure 2 Fig. 2 is a structural schematic diagram of a compact mid-ducted solid fuel ramjet engine according to an embodiment of the present application, (a) is an axial sectional view, and (b) is a radial sectional view of the connecting plate.

[0025] In the drawings, the following reference signs are used:

[0026] 1. Center cone; 2. Connecting plate; 3. Inlet duct; 4. Charge combustion chamber; 5. Supplementary combustion chamber; 6. Nozzle. DETAILED DESCRIPTION

[0027] The application will be described in greater detail with reference to the drawings and embodiments.

[0028] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of the present application.

[0029] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of the present application.

[0030] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0031] This invention proposes a compact solid-fuel ramjet engine with a central air intake. By introducing air into the middle of the aircraft, the central cone storing the warhead / control system and the engine air intake are optimized from a conventional parallel layout to an axially segmented layout. This avoids the long-distance flow of air captured by the engine from front to back, effectively shortens the length of the air intake, achieves a compact layout, and improves the space utilization of the solid-fuel ramjet engine.

[0032] As one aspect of the present invention, a compact central-intake solid-fuel ramjet engine is provided, such as... Figure 2 As shown, the engine, from front to back, consists of a central cone 1, connecting plates 2, an air intake duct 3, a propellant combustion chamber 4, a combustion chamber 5, and a nozzle 6. The central cone 1 and the air intake duct 3 are axially segmented, and are connected by several connecting plates 2 evenly arranged circumferentially. Using the configuration of this invention, the central cone and air intake duct are axially segmented, with the central cone located in front of the air intake duct. The size of the central cone and the flow area of ​​the air intake duct are decoupled. On the one hand, this significantly increases the usable diameter of the central cone and significantly reduces the length of the air intake duct, resulting in a compact engine structure. This solves the problems of excessively long air intake ducts and low engine space utilization caused by parallel layouts of the air intake duct and central cone. On the other hand, it avoids the limitation of the air intake duct cross-section design by the central cone.

[0033] In one embodiment of the present invention, there are 3-4 connecting plates for the central cone and the air intake, which are arranged symmetrically around the center of the engine axis.

[0034] In one embodiment of the invention, the connecting plate is a stiffener, and the central cone and the air intake are connected by a stiffener, which can improve space utilization. The leading edge of the connecting plate is in a supersonic environment, and the sweep angle of the connecting plate is large, preferably not less than 60°. The connecting plate has chamfers both front and rear along the airflow direction to reduce drag. While meeting load strength requirements, the size of the stiffener should be as small as possible to reduce drag.

[0035] In one embodiment of the invention, the rear section of the center cone can partially extend into the air intake, and the length constraint of the center cone is relatively weak, making the engine structure more compact. Preferably, the rear section of the center cone can be streamlined to reduce losses caused by airflow separation and improve engine performance.

[0036] In some embodiments of the present application, a middle air intake scheme is adopted, and the flow air is compressed through the front section of the center cone and expanded through the rear section of the center cone, and there is a certain low-energy flow after the center cone and before the air inlet, which causes the engine performance to decrease. To solve this problem, the present application adopts a suction removal active control scheme, a plurality of holes are processed at the windward position of the connecting plate, the holes are communicated to the openings on the air inlet shell to form a suction removal channel, and the low-energy flow is discharged to the outside of the engine through the connecting plate and the air inlet shell, and the number, size and position of the holes and the suction removal channel need to be designed according to the suction removal requirement.

[0037] In an embodiment of the present application, the center cone, air inlet and connecting plate assembly adopts a 3D printing integrated molding scheme, and the suction exhaust channel can be directly formed. Since the rear section of the center cone and the compression surface of the air inlet have high precision requirements, the key parts need to be finished and detected after molding.

[0038] The present application proposes a compact middle air intake solid fuel ramjet engine, the center cone and the air inlet are designed in axial segments, which greatly shortens the length of the engine and improves the space utilization; the center cone rear section adopts a low-resistance profile, and the suction removal channel is arranged in the rib plate to effectively improve the engine performance.

[0039] Features described and / or illustrated with respect to one example can be used in the same or similar manner in one or more other examples, and / or in combination with or in place of features in other examples.

[0040] It should be emphasized that the term "comprises / comprising" when used in this text refers to the presence of a feature, whole, step or component, but does not exclude the presence or addition of one or more other features, whole, step, component or combination thereof.

[0041] Many of the features and advantages of the embodiments are apparent from the detailed description, and accordingly, the appended claims should be construed to cover all such features and advantages within the true spirit and scope of the embodiments. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the embodiments of the present application to the exact construction and operation described and illustrated, and accordingly, all suitable modifications and equivalents can be resorted to as falling within the scope of the embodiments.

[0042] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0043] The part of the present application not described in detail is the technology known to those skilled in the art.

Claims

1. A compact, centrally-intake solid-fuel ramjet engine, characterized in that, The engine comprises, from front to back, a central cone, connecting plates, an air intake, a propellant combustion chamber, a combustion chamber, and a nozzle. The central cone and the air intake are arranged in axial segments, and the central cone and the air intake are connected by several connecting plates evenly arranged circumferentially.

2. The engine according to claim 1, characterized in that, There are 3 or 4 connecting plates, arranged symmetrically around the center of the engine axis.

3. The engine according to claim 1, characterized in that, The connecting plate is a stiffening plate, the sweep angle of the connecting plate is not less than 60°, and the connecting plate is provided with chamfers at both the front and back along the airflow direction.

4. The engine according to claim 1, characterized in that, The connecting plate has the smallest size while meeting the load strength requirements.

5. The engine according to claim 1, characterized in that, The rear section of the center cone extends into the air intake.

6. The engine according to claim 1, characterized in that, The rear section of the central cone adopts a streamlined design.

7. The engine according to claim 1, characterized in that, Several holes are machined at the windward position of the connecting plate, and the holes are connected to the openings on the air intake housing to form a suction channel.

8. The engine according to claim 1, characterized in that, The center cone, air intake, and connecting plate are integrally formed using 3D printing.

9. The engine according to claim 1, characterized in that, The centrally inlet solid fuel ramjet engine is used in extended-range projectiles.

Images