A wide speed range ramjet engine and combined power plant
By installing a high-temperature jet flame stabilizer assembly on the inner wall of the expanding tail nozzle of the ramjet engine, the operating speed range of the scramjet engine has been widened to Ma=3.0~7.0, solving the problem of insufficient speed range in the existing technology, realizing the combination with the Ma=3.0 class high-speed turbine engine, and reducing the overall technical difficulty.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- AERO ENGINE ACAD OF CHINA
- Filing Date
- 2026-04-30
- Publication Date
- 2026-06-16
AI Technical Summary
Existing technologies make it difficult to extend the operating speed range of scramjet engines to Ma=3.0~7.0, resulting in significant overall technical challenges when combining them with high-speed turbine engines of Ma=3.0.
A high-temperature jet flame stabilizer assembly is installed on the inner wall of the expanding tail nozzle in the ramjet channel. Utilizing the relatively large cross-sectional area of the flow channel at the front section of the expanding tail nozzle, the tail nozzle is used as a temporary equivalent ramjet combustion chamber. With the pre-injection and premixing of fuel, and by controlling the opening sequence of the high-temperature jet flame stabilizer, the momentum ratio between the incoming mixture and the high-temperature jet is kept constant, thereby achieving simultaneous acceleration of the combustion process.
Expanding the operating speed range of the ramjet engine to Ma=3.0~7.0 reduces the upper limit requirement of the speed range of the high-speed turbine engine and reduces the overall technical difficulty of the combined power unit.
Smart Images
Figure CN122215959A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of engine technology, and in particular to a wide-speed-range ramjet engine and its combined power unit. Background Technology
[0002] In combined power plants of high-speed turbine engines and scramjet engines operating at Mach numbers of 0 to 7.0, the conventional speed-range scramjet engine, with an operating speed range of Ma 4.0 to 7.0, requires at least a Ma 4.0-class high-speed turbine engine for combination, resulting in significant overall technical challenges. If the operating speed range of the scramjet engine could be broadened to Ma 3.0 to 7.0, it could be combined with a Ma 3.0-class high-speed turbine engine, thereby reducing the overall technical difficulty of such combined power plants. Therefore, how to broaden the operating speed range of conventional speed-range scramjet engines, lowering their lower limit, and thus reducing the upper limit requirement for high-speed turbine engines, thereby reducing the overall technical difficulty of such combined power plants, is one of the urgent technical problems to be solved in this field. Summary of the Invention
[0003] This disclosure is made in view of the above-mentioned problems. This disclosure provides a wide-speed-range ramjet engine and a combined power unit.
[0004] According to one aspect of this disclosure, a wide-speed-range ramjet engine is provided, including a ramjet passage, a front support plate fuel injector, a front cavity flame stabilizer, a rear support plate fuel injector, a rear cavity flame stabilizer, and a combination of a high-temperature jet flame stabilizer. The ramjet channel includes, in sequence, an air intake, an isolation section, a front section of the scramjet combustion chamber, a rear section of the scramjet combustion chamber, and an expanding tail nozzle; The front support plate fuel injector and the front cavity flame stabilizer are installed sequentially on the inner wall of the front section of the scramjet combustion chamber in the front-back direction. The rear support plate fuel injector and the rear cavity flame stabilizer are installed sequentially on the inner wall of the rear section of the scramjet combustion chamber in the front-to-back direction. The high-temperature jet flame stabilizer assembly is installed on the inner wall of the expanded tail nozzle near the rear section of the scramjet combustion chamber.
[0005] Furthermore, according to one aspect of this disclosure, a wide-speed-range ramjet engine, the high-temperature jet flame stabilizer assembly includes a first high-temperature jet flame stabilizer, a second high-temperature jet flame stabilizer, and a third high-temperature jet flame stabilizer; the first high-temperature jet flame stabilizer, the second high-temperature jet flame stabilizer, and the third high-temperature jet flame stabilizer are mounted on the inner wall of the expanding tail nozzle in the front-rear direction; The gas flow rates of the first high-temperature jet flame stabilizer, the second high-temperature jet flame stabilizer, and the third high-temperature jet flame stabilizer decrease sequentially.
[0006] Furthermore, according to one aspect of this disclosure, a wide-range ramjet engine has an expansion nozzle with an exhaust down-adjustment plate; one end of the exhaust down-adjustment plate is hinged to the wall of the rear section of the scramjet combustion chamber; a first high-temperature jet flame stabilizer, a second high-temperature jet flame stabilizer, and a third high-temperature jet flame stabilizer are mounted on the exhaust down-adjustment plate.
[0007] Furthermore, according to one aspect of this disclosure, a wide-speed-range ramjet engine has a first high-temperature jet flame stabilizer, a second high-temperature jet flame stabilizer, and a third high-temperature jet flame stabilizer installed on the inner wall of the expanding tail nozzle opposite to the exhaust lower regulating plate.
[0008] Furthermore, according to one aspect of this disclosure, in a wide-speed-range ramjet engine, the front support plate fuel injector and the front cavity flame stabilizer are both installed on the inner wall of the front section of the scramjet combustion chamber near the isolation section; the rear support plate fuel injector and the rear cavity flame stabilizer are both installed on the inner wall of the rear section of the scramjet combustion chamber near the front section of the scramjet combustion chamber.
[0009] Furthermore, according to one aspect of this disclosure, in a wide-range ramjet engine, the cross-sectional area of the intake gradually decreases along the direction approaching the isolation section; the cross-sectional areas of the isolation section and the front section of the scramjet combustion chamber are the same, and the cross-sectional area of the isolation section is equal to the minimum cross-sectional area of the intake; the cross-sectional area of the rear section of the scramjet combustion chamber gradually increases along the direction away from the front section of the scramjet combustion chamber.
[0010] Furthermore, according to one aspect of this disclosure, a wide-range ramjet engine has a tail nozzle thermal throat operating mode and a dual-mode scramjet mode; when in the tail nozzle thermal throat operating mode, the flight Mach number corresponding to the wide-range ramjet engine is between a first Mach number and a second Mach number. The dual-mode scramjet mode includes a sub-spinning mode and a scramjet mode; when in sub-spinning mode, the flight Mach number corresponding to the wide-range ramjet engine is between the second Mach number and the third Mach number; When in scramjet mode, the flight Mach number of the wide-range ramjet engine is between the third and fourth Mach numbers.
[0011] Furthermore, according to one aspect of this disclosure, in the thermal throat operating mode of the tail nozzle, when the flight Mach number is between the first Mach number and the fifth Mach number, the third high-temperature jet flame stabilizer is in the open state, and the first high-temperature jet flame stabilizer and the second high-temperature jet flame stabilizer are in the closed state; when the flight Mach number is between the fifth Mach number and the sixth Mach number, the second high-temperature jet flame stabilizer is in the open state, and the first high-temperature jet flame stabilizer and the third high-temperature jet flame stabilizer are in the closed state; when the flight Mach number is between the sixth Mach number and the second Mach number, the first high-temperature jet flame stabilizer is in the open state, and the second high-temperature jet flame stabilizer and the third high-temperature jet flame stabilizer are in the closed state.
[0012] Furthermore, according to a wide-speed-range ramjet engine of one aspect of this disclosure, the calculation formula for the activation sequence of the first high-temperature jet flame stabilizer, the second high-temperature jet flame stabilizer, and the third high-temperature jet flame stabilizer is as follows: ,in, This refers to the mass flow rate of the incoming air-fuel mixture in the area in front of the tail nozzle. The average velocity of the incoming flow in the area in front of the tail nozzle. The jet mass flow rate of the high-temperature jet flame stabilizer. The jet velocity of the high-temperature jet flame stabilizer. This is an empirical constant.
[0013] According to another aspect of this disclosure, a combined power unit is provided, comprising a high-speed turbine engine and a wide-range ramjet engine as described above. The combined power unit is provided with a high-speed turbine engine channel, and the high-speed turbine engine is installed in the high-speed turbine engine channel; the high-speed turbine engine channel and the ramming channel of the wide-speed range ramjet engine are arranged in parallel vertically; the inlet of the high-speed turbine engine channel is provided with an intake upper adjustment plate and the outlet is provided with an exhaust upper adjustment plate.
[0014] This disclosure utilizes a combination of high-temperature jet flame stabilizers installed on the inner wall of the expanding nozzle in the ramjet channel. This effectively leverages the relatively large cross-sectional area of the front section of the expanding nozzle, treating the nozzle as a temporary equivalent ramjet combustion chamber. Combined with pre-injection and premixing of fuel, during low-speed acceleration, the high-temperature jet flame stabilizers of varying flow rates located on the front wall of the nozzle are sequentially activated. This maintains a relatively constant momentum ratio between the incoming air-fuel mixture and the high-temperature jet in different speed ranges, fully utilizing the ignition and flame stabilization capabilities of the high-temperature jet flame stabilizers. Simultaneously, a thermal throat is established in the front section of the nozzle, accelerating the combustion gas from subsonic to supersonic speeds while maintaining expansion acceleration capability. With a relatively simple aerodynamic and thermodynamic adjustment method, the operating speed range of the ramjet engine is broadened to Ma=3.0–7.0, allowing it to be combined with high-speed turbine engines of Ma=0–3.0, effectively reducing the overall technical difficulty of such combined power units. Attached Figure Description
[0015] The above and other objects, features, and advantages of this disclosure will become more apparent from the more detailed description of the embodiments thereof in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this disclosure and form part of the specification. They are used together with the embodiments of this disclosure to explain the disclosure and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.
[0016] Figure 1 This is a schematic diagram of the structure of a wide-speed-range ramjet engine disclosed in this publication.
[0017] Figure 2 This is a schematic diagram showing the state of the third high-temperature jet flame stabilizer when the wide-speed-range ramjet engine is in the tail nozzle thermal throat working mode.
[0018] Figure 3 This is a schematic diagram showing the state of the second high-temperature jet flame stabilizer when the wide-speed-range ramjet engine is in the tail nozzle thermal throat working mode.
[0019] Figure 4 This is a schematic diagram showing the state of the first high-temperature jet flame stabilizer when the wide-speed-range ramjet engine is in the tail nozzle thermal throat working mode.
[0020] Figure 5 This is the typical pressure distribution along the flow path in the tail nozzle thermal throat mode.
[0021] Figure 6 This is a schematic diagram of the sub-gas combustion mode working mechanism of a dual-mode scramjet engine.
[0022] Figure 7This is a typical pressure distribution along the flow path in the sub-burning mode of a dual-mode scramjet engine.
[0023] Figure 8 This is a schematic diagram of the scramjet mode working mechanism of a dual-mode scramjet engine.
[0024] Figure 9 This is a typical pressure distribution along the flow path in the scramjet mode of a dual-mode scramjet engine.
[0025] Figure 10 It is the basic principle of high-temperature jet flame stabilization adopted in the thermal throat working mode of the tail nozzle.
[0026] Figure 11 This is a schematic diagram illustrating the speed range transition between a high-speed turbine engine and a wide-speed-range ramjet engine.
[0027] Figure 12 This is a schematic diagram of the combined power unit disclosed in this publication when only the turbine engine is working.
[0028] Figure 13 This is a schematic diagram showing the state of the third high-temperature jet flame stabilizer when only the wide-speed-range ramjet engine of the combined power unit is working and in the thermal throat mode of the tail nozzle.
[0029] Figure 14 This is a schematic diagram showing the state of the second high-temperature jet flame stabilizer when only the wide-speed-range ramjet engine of the combined power unit is working and in the thermal throat working mode of the tail nozzle.
[0030] Figure 15 This is a schematic diagram showing the state of the first high-temperature jet flame stabilizer when only the wide-speed-range ramjet engine of the combined power unit is working and in the thermal throat working mode of the tail nozzle.
[0031] Figure 16 This is a schematic diagram of the sub-gas combustion mode of the dual-mode scramjet engine operating in a combined power unit.
[0032] Figure 17 This is a schematic diagram of the state of the dual-mode scramjet engine of the combined power unit in scramjet mode.
[0033] Explanation of reference numerals in the attached figures: 1-High-speed turbine engine passage, 2-Ramjet passage, 3-High-speed turbine engine, 5-Intake upper adjustment plate, 6-Exhaust upper adjustment plate, 7-Intake lower adjustment plate, 8-Exhaust lower adjustment plate, 9-Intake duct, 10-Isolation section, 11-Front section of scramjet combustion chamber, 12-Front section support plate fuel injector, 13-Front section concave flame stabilizer, 14-Rear section of scramjet combustion chamber, 15-Rear section support plate fuel injector, 16-Rear section concave flame stabilizer, 17-Expanding tail nozzle, 18-First high-temperature jet flame stabilizer, 19-Second high-temperature jet flame stabilizer 20-Third high-temperature jet flame stabilizer, 21-Incoming air, 22-First oblique shock wave system, 23-First normal shock wave chain, 25-Second normal shock wave chain, 26-Weak normal shock wave chain, 28-First stable flame zone, 27-Premixed gas, 29-First thermal throat, 31-Second oblique shock wave system, 32-Third normal shock wave chain, 33-Fourth normal shock wave chain, 35-First high-temperature recirculation zone, 36-Second stable flame zone, 37-Second thermal throat, 39-Third oblique shock wave system, 40-Oblique shock wave chain, 41-Second high-temperature recirculation zone, 43-Third stable flame zone. Detailed Implementation
[0034] To make the objectives, technical solutions, and advantages of this disclosure more apparent, exemplary embodiments according to this disclosure will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments of this disclosure. It should be understood that this disclosure is not limited to the exemplary embodiments described herein.
[0035] See Figures 1-11 As shown, this disclosure discloses a wide-speed-range ramjet engine, including a ramjet channel 2, a front support plate fuel injector 12, a front cavity flame stabilizer 13, a rear support plate fuel injector 15, a rear cavity flame stabilizer 16, and a combination of a high-temperature jet flame stabilizer. The ramjet channel 2 includes, in sequence, an intake duct 9, an isolation section 10, a front section 11 of the scramjet combustor, a rear section 14 of the scramjet combustor, and an expanding tail nozzle 17; the cross-sectional area of the intake duct 9 gradually decreases along the direction close to the isolation section 10; the cross-sectional areas of the isolation section 10 and the front section 11 of the scramjet combustor are the same, and the cross-sectional area of the isolation section 10 is equal to the minimum cross-sectional area of the intake duct 9; the cross-sectional area of the rear section 14 of the scramjet combustor gradually increases along the direction away from the front section 11 of the scramjet combustor.
[0036] The front-end fuel injector 12 and the front-end concave flame stabilizer 13 are sequentially installed on the inner wall of the front section 11 of the scramjet combustor in a front-back direction; here, the front-back direction refers to the direction from the intake duct 9 to the expanding tail nozzle 17, with the intake duct 9 in front and the expanding tail nozzle 17 behind. Both the front-end fuel injector 12 and the front-end concave flame stabilizer 13 are installed on the inner wall of the front section 11 of the scramjet combustor near the isolator section 10.
[0037] The rear-stage support plate fuel injector 15 and the rear-stage recessed flame stabilizer 16 are sequentially installed on the inner wall of the rear section 14 of the scramjet combustion chamber in a front-rear direction; here, the front-rear direction refers to the direction from the intake duct 9 to the expanding tail nozzle 17. The rear-stage support plate fuel injector 15 and the rear-stage recessed flame stabilizer 16 are both installed on the inner wall of the rear section 14 of the scramjet combustion chamber near the front section 11 of the scramjet combustion chamber.
[0038] The high-temperature jet flame stabilizer assembly is installed on the inner wall of the expanding nozzle 17 near the rear section 14 of the scramjet combustor. The high-temperature jet flame stabilizer assembly includes a first high-temperature jet flame stabilizer 18, a second high-temperature jet flame stabilizer 19, and a third high-temperature jet flame stabilizer 20; the first high-temperature jet flame stabilizer 18, the second high-temperature jet flame stabilizer 19, and the third high-temperature jet flame stabilizer 20 are installed on the inner wall of the expanding nozzle 17 in a front-rear direction; here, the front-rear direction refers to the direction along the expanding nozzle 17 away from the rear section 14 of the scramjet combustor.
[0039] The gas flow rates of the first high-temperature jet flame stabilizer 18, the second high-temperature jet flame stabilizer 19, and the third high-temperature jet flame stabilizer 20 decrease sequentially.
[0040] The wide-range ramjet engine has a tail nozzle thermal throat operating mode and a dual-mode scramjet mode. In the tail nozzle thermal throat operating mode, the corresponding flight Mach number of the wide-range ramjet engine is between Mach 1 and Mach 2, and includes both Mach 1 and Mach 2. In the tail nozzle thermal throat operating mode, when the flight Mach number is between Mach 1 and Mach 5, and includes both Mach 1 and Mach 5, the third high-temperature jet flame stabilizer 20 is in the open state, and the first high-temperature jet flame stabilizer 18 and the second high-temperature jet flame stabilizer... 19 is in the off state; when the flight Mach number is between Mach 5 and Mach 6, and includes both Mach 5 and Mach 6, the second high-temperature jet flame stabilizer 19 is in the on state, and the first high-temperature jet flame stabilizer 18 and the third high-temperature jet flame stabilizer 20 are in the off state; when the flight Mach number is between Mach 6 and Mach 2, and includes both Mach 6 and Mach 20, the first high-temperature jet flame stabilizer 18 is in the on state, and the second high-temperature jet flame stabilizer 19 and the third high-temperature jet flame stabilizer 20 are in the off state.
[0041] The dual-mode scramjet engine includes a sub-spinning mode and a scramjet mode; when in sub-spinning mode, the flight Mach number of the wide-range ramjet engine is between the second and third Mach numbers; When in scramjet mode, the flight Mach number of the wide-range ramjet engine is between Mach 3 and Mach 4.
[0042] The working mechanism of the tail nozzle thermal throat working mode is as follows: Figures 2-4 As shown, and in combination Figure 1 To provide a more detailed explanation.
[0043] After the incoming air 21 is pre-compressed by the first oblique shock wave system 22 in the intake duct 9, it continues to be compressed by the first normal shock wave chain 23 formed in the isolation section and flows into the front section 11 of the scramjet combustion chamber. At this time, the front support plate fuel injector 12 is opened to inject fuel, and the fuel begins to gradually mix with the incoming air 21 to form a premixed combustible gas, but the ignition device is not activated. The front cavity flame stabilizer 13 only forms a cold recirculation zone. There is no combustion zone in the front section 11 of the scramjet combustion chamber, which is temporarily equivalent to an isolation section to accommodate the second normal shock wave chain 25. After the premixed gas of the incoming air 21 and fuel is compressed again by this part of the normal shock wave chain 25, it flows into the rear section 14 of the scramjet combustion chamber. At this time, the rear section support plate fuel injector 15 is closed, and the rear section concave cavity flame stabilizer only forms a cold recirculation zone. The rear section 14 of the scramjet combustion chamber has no combustion zone and is temporarily equivalent to an isolation section, used to accommodate a portion of the weak positive shock wave chain 26. The premixed gas 27, after the incoming air 21 and fuel are fully mixed, continues to be compressed after passing through this portion of the weak positive shock wave chain 26 and flows into the front section of the expanding tail nozzle 17 at a high subsonic speed (e.g., Ma=0.6~0.8). At this time, the three sets of high-temperature jet flame stabilizers 20 (small flow), 19 (medium flow), and 18 (large flow) with different flow rates, located on the wall of the front section of the expanding tail nozzle 17, are opened sequentially. The principle for the opening sequence is to maintain a relatively constant ratio between the momentum of the incoming mixed gas and the momentum of the high-temperature jet in the front region of the tail nozzle during the aircraft's acceleration process. ,in, This refers to the mass flow rate of the incoming air-fuel mixture in the area in front of the tail nozzle. The average velocity of the incoming flow in the area in front of the tail nozzle. The jet mass flow rate of the high-temperature jet flame stabilizer. The jet velocity of the high-temperature jet flame stabilizer. This is an empirical constant. This empirical constant is the one that maintains the high-temperature jet flame stabilizer with suitable ignition and flame stabilization capabilities. The basic principle of the above criterion is that when an aircraft accelerates at high altitudes, the flow rate of the ramjet channel mixture continuously increases, and the main flow rate in the front region of the tail nozzle increases accordingly. In order to maintain good ignition and flame stabilization capabilities of the high-temperature jet flame stabilizer during changes in the main flow rate, thus forming a thermal throat, the ratio of the high-temperature jet momentum to the momentum of the incoming flow mixture must be maintained at a certain threshold. This momentum ratio can usually be maintained as an empirical constant. Therefore, a corresponding increase in the high-temperature jet momentum is required during acceleration. A simple method is to set up several sets of high-temperature jet flame stabilizers with different flow rates and control them to activate sequentially. Thus, there is a specific correspondence between the activation sequence of the high-temperature jet flame stabilizers and the speed range in the low-speed segment. Based on the principle of constant momentum ratio, the activation sequence of the high-temperature jet flame stabilizer combination during the acceleration of aircraft at high altitudes is low flow rate, medium flow rate, and high flow rate. Another issue is how to determine the arrangement order of high-temperature jet flame stabilizers with different flow rates on the inner wall of the tail nozzle. Specifically, this is determined based on the thrust requirements of the engine during the aircraft's acceleration. When the aircraft accelerates at a constant altitude, the aerodynamic drag of the aircraft increases, and the thrust of the ramjet engine required to maintain acceleration also increases accordingly. Consequently, the combustion chamber pressure also needs to be increased. That is, with the same total amount and ratio of fuel and air, the combustion heat release area should move to a smaller space to increase the energy release rate per unit volume. Therefore, during the aircraft's acceleration at a constant altitude, the combustion heat release space of the equivalent combustion chamber (i.e., the front section of the tail nozzle) should gradually shrink, that is, the heat release area should gradually move forward to increase the pressure of the equivalent combustion chamber and increase the thrust of the ramjet engine. Combining this with the principle of constant momentum ratio during acceleration, the final arrangement order of the high-temperature jet flame stabilizers along the inner wall of the tail nozzle from front to back should be: high flow rate, medium flow rate, and low flow rate.
[0044] In one implementation, taking a first Mach number of 3.0, a second Mach number of 4.0, a third Mach number of 5.5, a fourth Mach number of 7.0, a fifth Mach number of 3.3, and a sixth Mach number of 3.6 as an example, that is, when in the tail nozzle thermal throat operating mode, the flight Mach number corresponding to the wide-speed-range ramjet engine is Ma=3.0~4.0; when in subsonic combustion mode, the flight Mach number corresponding to the wide-speed-range ramjet engine is Ma=4.0~5.5; and when in scramjet mode, the flight Mach number corresponding to the wide-speed-range ramjet engine is Ma=5.5~7.0. In the tail nozzle thermal throat operating mode, when the flight Mach number Ma=3.0~3.3, the third high-temperature jet flame stabilizer 20 is activated. Figure 2 As shown; when Ma=3.3~3.6, the second high-temperature jet flame stabilizer 19 located in the middle is activated. Figure 3 As shown; when Ma=3.6~4.0, the first high-temperature jet flame stabilizer 18 is activated. Figure 4As shown, the high-temperature jet fuel-air mixture forms a first stable flame zone 28 with a very high combustion heat release rate. Due to the thorough mixing of fuel and incoming air 21 over a long distance in the channel, coupled with the appropriate matching of different incoming flow velocity ranges and flow rates of the first, second, and third high-temperature jet flame stabilizers 18, 19, and 20, the combustion heat release rate in the corresponding region is extremely high, resulting in the sequential formation of first thermal throats 29 at different positions in front of the expanding nozzle 17. Furthermore, in the low-speed range of Ma=3.0–4.0, as the flight speed increases and the opening position of the high-temperature jet flame stabilizers moves forward, the position of the first thermal throat 29 also gradually moves forward. The subsonic high-temperature airflow in the front section of the expanding nozzle 17 is accelerated to the local speed of sound through the "first thermal throat" 29. After passing the speed of sound point, it continues to accelerate into a supersonic high-temperature airflow in the rear section of the expanding nozzle 17, completing the expansion acceleration process. In practice, during the aforementioned process, the expanding nozzle 17 temporarily serves as both a combustion chamber and a nozzle. This process creates a typical pressure distribution along the flow path in the nozzle's thermal throat mode, such as... Figure 5 As shown.
[0045] The wide-speed-range ramjet engine of this application has a wider operating speed range, which can extend the lower limit of its operating speed range to Ma=3.0, reducing the requirement for the upper limit of the operating speed range of the high-speed turbine engine, making it possible to combine with a high-speed turbine engine of Ma=3.0 level, and reducing the overall technical difficulty of such combined power units.
[0046] The sub-gas mode working mechanism of the dual-mode scramjet press is as follows: Figure 6 As shown, and in combination Figure 1 Please provide a detailed explanation.
[0047] After the incoming air 21 is pre-compressed by the second oblique shock wave system 31 in the intake duct 9, it is further compressed by the third normal shock wave chain 32 formed in the isolation section 10 and flows into the front section 11 of the scramjet combustion chamber. At this time, the front support plate fuel injector 12 is closed, and the front cavity flame stabilizer 13 only forms a cold recirculation zone. The front section 11 of the scramjet combustion chamber does not have a combustion zone, but instead accommodates a portion of the fourth normal shock wave chain 33. After the incoming air 21 is compressed again by this portion of the fourth normal shock wave chain 33, it flows into the rear section 14 of the scramjet combustion chamber at a high subsonic speed (e.g., Ma=0.6~0.8). The rear support plate fuel injector 15 is opened to inject fuel, which effectively mixes with the compressed incoming air and ignites it. The rear cavity flame stabilizer 16 forms a first high-temperature recirculation zone 35 to stabilize the flame, and together with the rear support plate fuel injector 15, it supports the flame propagation and expansion in the mainstream area of the combustion chamber to form a second stable flame zone 36. In the expansion-type rear section flow channel of the scramjet combustor, due to the proper matching of the flow process, heat release process, and flow channel profile, a second thermal throat 37 is formed at a certain location. The subsonic high-temperature gas flow in the combustor is accelerated to the local sound speed through the second thermal throat 37, and continues to accelerate into a supersonic high-temperature gas flow after passing the sound speed point. That is, the gas flow velocity in the rear section 14 flow channel of the scramjet combustor undergoes a high subsonic-sonic-supersonic process. The high-temperature jet flame stabilizer assembly (first high-temperature jet flame stabilizer 18, second high-temperature jet flame stabilizer 19, and third high-temperature jet flame stabilizer 20) located on the front wall of the expansion-type tail nozzle 17 is closed, and the supersonic high-temperature gas flow completes the expansion and acceleration process in the expansion-type tail nozzle 17. The above process forms the typical pressure distribution along the flow channel in the subsonic mode of the dual-mode scramjet engine, such as... Figure 7 As shown.
[0048] The working mechanism of the scramjet mode in the dual-mode scramjet pressing is as follows: Figure 8 As shown, and in combination Figure 1 Please provide a detailed explanation.
[0049] After being pre-compressed by the third oblique shock system 39 in the intake duct 9, the incoming air 21 is further compressed by the oblique shock chain 40 formed in the isolation section 10 and flows into the front section 11 of the scramjet combustor at supersonic speed. The front support plate fuel injector 12 opens to inject fuel, and the front cavity flame stabilizer 13 forms the second high-temperature recirculation zone 41 to stabilize the flame. At the same time, together with the front support plate fuel injector 12, it supports the flame propagation and expansion in the mainstream area of the combustor to form the third stable flame zone 43. At this time, the rear support plate fuel injector 15 closes, and the rear section 14 of the scramjet combustor serves as an extension of the front section 11 of the scramjet combustor, where fuel and incoming air 21 continue to mix and burn completely. In the flow channels of the front section 11 and the rear section 14 of the scramjet combustor, the airflow maintains supersonic speed throughout. The high-temperature jet flame stabilizer assembly (first high-temperature jet flame stabilizer 18, second high-temperature jet flame stabilizer 19, and third high-temperature jet flame stabilizer 20) located on the front wall of the expanding nozzle 17 is closed, and the supersonic high-temperature gas flow completes the expansion and acceleration process in the expanding nozzle 17. This process forms the typical pressure distribution along the flow path in the scramjet mode of a dual-mode scramjet engine, such as... Figure 9 As shown.
[0050] Furthermore, the expanding tail nozzle 17 has an exhaust lower regulating plate 8; one end of the exhaust lower regulating plate 8 is hinged to the wall of the rear section 14 of the scramjet combustion chamber; a first high-temperature jet flame stabilizer 18, a second high-temperature jet flame stabilizer 19, and a third high-temperature jet flame stabilizer 20 are installed on the exhaust lower regulating plate 8.
[0051] Furthermore, a first high-temperature jet flame stabilizer 18, a second high-temperature jet flame stabilizer 19, and a third high-temperature jet flame stabilizer 20 are installed on the inner wall of the expanding tail nozzle 17 opposite to the exhaust lower regulating plate 8. Figure 1 As shown.
[0052] This disclosure also discloses a combined power unit, including a high-speed turbine engine 3 and a wide-range ramjet engine as described above. Figures 12-17 As shown; The combined power unit is provided with a high-speed turbine engine channel 1, and a high-speed turbine engine 3 is installed in the high-speed turbine engine channel 1; the high-speed turbine engine channel 1 and the ramjet channel 2 of the wide speed range ramjet engine are arranged in parallel, one above the other; the inlet of the high-speed turbine engine channel 1 is provided with an upper intake regulating plate 5 and the outlet is provided with an upper exhaust regulating plate 6, and the inlet of the intake duct 9 of the ramjet channel 2 is provided with a lower intake regulating plate 7.
[0053] As one implementation method, a high-speed turbine engine 3 with Ma=0 to 3.0 is installed in the high-speed turbine engine channel 1, and the operating speed range of the wide-speed-range ramjet engine is Ma=3.0 to 7.0; This combined propulsion system, in flight conditions of Ma=0 to 3.0, such as Figure 12 As shown, only the high-speed turbine engine is operating, with the upper intake regulating plate 5 and the upper exhaust regulating plate 6 open, and the lower intake regulating plate 7 and the lower exhaust regulating plate 8 also remaining open. The ramjet passage is in a cold flow state. The shaded area in the high-speed turbine engine passage 1 represents the area occupied by the high-temperature exhaust gas from the high-speed turbine engine 3 in this mode. This combined power unit operates as follows during flight at Mach 3.0–4.0: Figures 13-15 As shown, the high-speed turbine engine 3 stops working, the upper intake regulating plate 5 and the upper exhaust regulating plate 6 are closed, the lower intake regulating plate 7 and the lower exhaust regulating plate 8 remain open, and the ramjet channel 2 is in the tailpipe thermal throat working mode. Figure 13 This indicates that when Ma = 3.0 to 3.3, the third high-temperature jet flame stabilizer 20 with a small flow rate is in the open state. Figure 14 This indicates that when Ma = 3.3–3.6, the second high-temperature jet flame stabilizer 19 with medium flow rate is in the open state, where... Figure 15 This indicates that at Ma=3.6–4.0, the high-flow-rate first high-temperature jet flame stabilizer 18 is in the open state, and the shaded area in the channel represents the region occupied by the high-temperature gas in the expanding tailpipe during this mode. When this combined propulsion system is in flight at Ma=4.0–5.5, such as… Figure 16 As shown, the high-speed turbine engine 3 stops operating, the upper intake regulating plate 5 and the upper exhaust regulating plate 6 are closed, and the lower intake regulating plate 7 and the lower exhaust regulating plate 8 remain open. The wide-range ramjet engine is in the sub-combustion mode of the dual-mode scramjet engine. The shaded area in the channel represents the region occupied by the high-temperature gas in the rear section of the scramjet combustion chamber and the expanding tail nozzle at this time. This combined power unit operates as follows during flight at Mach 5.5–7.0: Figure 17 As shown, the high-speed turbine engine 3 stops working, the upper intake regulating plate 5 and the upper exhaust regulating plate 6 are closed, and the lower intake regulating plate 7 and the lower exhaust regulating plate 8 remain open. The wide-speed-range ramjet engine is in the supersonic mode when it is in the dual-mode supersonic ramjet engine mode. The shaded part in the channel represents the area occupied by the high-temperature gas in the front section, rear section and expansion nozzle of the supersonic ramjet combustion chamber at this time.
[0054] The concept of speed range transition between high-speed turbocharged engines and wide-speed-range ramjet engines, such as... Figure 11As shown. The operating range of the high-speed turbine engine is Ma=0~3.0, therefore it cannot be directly connected with the speed range of the conventional speed range scramjet engine (Ma=4.0~7.0). A wide-range ramjet engine using nozzle thermal throat technology can widen the lower limit of the ramjet channel's operating speed range to Ma=3.0. At Ma=3.0~4.0, the wide-range ramjet engine operates in nozzle thermal throat mode. At Ma=4.0~7.0, the wide-range ramjet engine operates in dual-mode scramjet engine mode, where it operates in sub-combustion mode at Ma=4.0~5.5 and in scramjet mode at Ma=5.5~7.0. The combination of the high-speed turbine engine and the wide-range ramjet engine based on nozzle thermal throat technology forms a combined power unit that can effectively operate within the Ma=0~7.0 range.
[0055] The basic principle of high-temperature jet flame stabilization used in the thermal throat working mode of the tail nozzle, such as... Figure 10 As shown. When the wide-speed-range ramjet engine of the combined power unit is operating, fuel pressurization can be achieved using a gas turbopump system. In this system, the high-temperature gas flow generated by the gas generator, after being expanded by the turbine, produces a hot gas flow that can be used as an ignition flame for ignition and flame stabilization in the front section of the expanding tail nozzle. The hot gas flow (temperature T2, typical value 1000K) discharged from the gas turbopump system is introduced into the cold oil-gas mixture (temperature T1), and the flow velocities of the two airflows are kept different (V1≠V2). At this time, the hot and cold airflows will exchange mass and heat in the cross-sectional and axial directions. The chemical reaction rate and flame propagation speed of the cold oil-gas mixture will be increased accordingly, and it will be ignited under suitable parameter conditions to form a stable flame. Using the above-mentioned flame stabilization method in the front section of the expanding tail nozzle does not require the addition of complex mechanical flame stabilization devices or the installation of a dedicated hot gas flow generator. It only requires the installation of a switching valve on the gas pipeline between the turbopump hot gas flow exhaust port and the jet flame stabilizer. During the acceleration of the aircraft, the hot gas flow is sequentially switched to the low-flow third high-temperature jet flame stabilizer 20, the medium-flow second high-temperature jet flame stabilizer 19, and the high-flow first high-temperature jet flame stabilizer 18. Therefore, it has good feasibility.
[0056] The wide-speed-range ramjet engine employs a different technical approach compared to the method of adjusting the flow channel geometry, which utilizes the existing conditions of the aircraft (e.g., high-temperature exhaust from the gas turbine pump) and rationally controls the aerodynamic and thermodynamic parameters of the nozzle region at flight Mach numbers Ma=3.0–4.0 by setting up a relatively simple combination of high-temperature jet flame stabilizers. This achieves the goal of widening the lower limit of the ramjet engine's speed range, and has lower overall technical difficulty compared to the method of widening the lower limit of the speed range through geometric adjustment.
[0057] This application uses the flow channel of a dual-mode scramjet engine in the conventional speed range of Ma=4.0 to 7.0 as the basic flow channel. At relatively low speeds of Ma=3.0 to 4.0, it effectively utilizes the relatively large cross-sectional area of the front section of the expanding nozzle 17, using the expanding nozzle 17 as a temporary equivalent ramjet combustion chamber. With the help of pre-injected and premixed fuel, during acceleration in the low-speed range, the high-temperature jet flame stabilizers (first high-temperature jet flame stabilizer 18, second high-temperature jet flame stabilizer 19, and third high-temperature jet flame stabilizer 20) located on the front wall of the expanding nozzle 17 are sequentially activated. By maintaining a relatively constant momentum ratio between the incoming air-fuel mixture and the high-temperature jet across different velocity ranges, the ignition and flame stabilization capabilities of the high-temperature jet flame stabilizer are fully utilized, ensuring the establishment of the "thermal throat." This allows the high-temperature airflow in the expanding nozzle to complete continuous changes at subsonic, sonic, and supersonic speeds, achieving combustion while maintaining expansion and acceleration capabilities. With a relatively simple aero-thermodynamic adjustment method, the operating speed range of the ramjet engine is broadened to Ma=3.0–7.0, enabling it to be combined with high-speed turbine engines of Ma=0–3.0, effectively reducing the overall technical difficulty of such combined power units.
[0058] Figure 2 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 The numbers “i, f, g, h, d, e” in the stamping channel 2 are the inlet and outlet section numbers of each component.
[0059] The basic principles of this disclosure have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this disclosure are merely examples and not limitations, and should not be considered as essential features of each embodiment of this disclosure. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the scope of this disclosure to the necessity of employing the aforementioned specific details for implementation.
[0060] The block diagrams of devices, apparatuses, devices, and systems disclosed herein are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.
[0061] Additionally, as used herein, the "or" used in a list of items beginning with "at least one" indicates a separate list, such that a list of, for example, "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the word "exemplary" does not imply that the described example is preferred or better than other examples.
[0062] It should also be noted that in the systems and methods of this disclosure, the components or steps can be decomposed and / or recombined. These decompositions and / or recombinations should be considered as equivalent solutions to this disclosure.
[0063] Various changes, substitutions, and modifications can be made to the technology described herein without departing from the teachings defined by the appended claims. Furthermore, the scope of the claims of this disclosure is not limited to the specific aspects of the processes, machines, manufactures, events, means, methods, and actions described above. Currently existing or later-developed processes, machines, manufactures, events, means, methods, or actions that perform substantially the same function or achieve substantially the same result as the corresponding aspects described herein can be utilized. Therefore, the appended claims include such processes, machines, manufactures, events, means, methods, or actions within their scope.
[0064] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.
[0065] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this disclosure to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations therein.
Claims
1. A wide-speed-range ramjet engine, characterized in that, It includes a combination of a stamping channel (2), a front support plate fuel injector (12), a front cavity flame stabilizer (13), a rear support plate fuel injector (15), a rear cavity flame stabilizer (16), and a high-temperature jet flame stabilizer. The ramjet channel (2) includes, in sequence, an air intake (9), an isolation section (10), a front section (11) of the scramjet combustion chamber, a rear section (14) of the scramjet combustion chamber, and an expansion nozzle (17). The front support plate fuel injector (12) and the front cavity flame stabilizer (13) are installed sequentially on the inner wall of the front section (11) of the supercharged ramjet combustion chamber in the front-back direction; The rear support plate fuel injector (15) and the rear cavity flame stabilizer (16) are installed sequentially on the inner wall of the rear section (14) of the supercharged ramjet combustion chamber in the front-back direction. The high-temperature jet flame stabilizer assembly is installed on the inner wall of the expanded tail nozzle (17) near the rear section (14) of the scramjet combustion chamber.
2. The wide-speed-range ramjet engine according to claim 1, characterized in that, The high-temperature jet flame stabilizer assembly includes a first high-temperature jet flame stabilizer (18), a second high-temperature jet flame stabilizer (19), and a third high-temperature jet flame stabilizer (20); the first high-temperature jet flame stabilizer (18), the second high-temperature jet flame stabilizer (19), and the third high-temperature jet flame stabilizer (20) are installed on the inner wall of the expanding tail nozzle (17) in the front-rear direction; The gas flow rates of the first high-temperature jet flame stabilizer (18), the second high-temperature jet flame stabilizer (19), and the third high-temperature jet flame stabilizer (20) decrease sequentially.
3. The wide-speed-range ramjet engine according to claim 2, characterized in that, The expanded tail nozzle (17) has an exhaust lower adjustment plate (8); one end of the exhaust lower adjustment plate (8) is hinged to the wall of the rear section (14) of the scramjet combustion chamber; the exhaust lower adjustment plate (8) is equipped with the first high temperature jet flame stabilizer (18), the second high temperature jet flame stabilizer (19), and the third high temperature jet flame stabilizer (20).
4. The wide-speed-range ramjet engine according to claim 3, characterized in that, The first high-temperature jet flame stabilizer (18), the second high-temperature jet flame stabilizer (19), and the third high-temperature jet flame stabilizer (20) are installed on the inner wall of the expanding tail nozzle (17) opposite to the exhaust lower regulating plate (8).
5. The wide-speed-range ramjet engine according to claim 4, characterized in that, The front support plate fuel injector (12) and the front cavity flame stabilizer (13) are both installed on the inner wall of the front section (11) of the scramjet combustion chamber near the isolation section (10); the rear support plate fuel injector (15) and the rear cavity flame stabilizer (16) are both installed on the inner wall of the rear section (14) of the scramjet combustion chamber near the front section (11) of the scramjet combustion chamber.
6. The wide-speed-range ramjet engine according to claim 5, characterized in that, The cross-sectional area of the intake duct (9) gradually decreases along the direction close to the isolation section (10); the cross-sectional area of the isolation section (10) and the front section (11) of the scramjet combustion chamber are the same, and the cross-sectional area of the isolation section (10) is equal to the minimum cross-sectional area of the intake duct (9); the cross-sectional area of the rear section (14) of the scramjet combustion chamber gradually increases along the direction away from the front section (11) of the scramjet combustion chamber.
7. The wide-speed-range ramjet engine according to claim 2, characterized in that, The wide-range ramjet engine has a tail nozzle thermal throat operating mode and a dual-mode scramjet mode; when in the tail nozzle thermal throat operating mode, the flight Mach number of the wide-range ramjet engine is between the first Mach number and the second Mach number. The dual-mode scramjet mode includes a sub-spinning mode and a scramjet mode; when in sub-spinning mode, the flight Mach number corresponding to the wide-range ramjet engine is between the second Mach number and the third Mach number; When in scramjet mode, the flight Mach number of the wide-range ramjet engine is between the third and fourth Mach numbers.
8. The wide-speed-range ramjet engine according to claim 7, characterized in that, In the tailpipe thermal throat working mode, when the flight Mach number is between the first Mach number and the fifth Mach number, the third high-temperature jet flame stabilizer (20) is in the open state, and the first high-temperature jet flame stabilizer (18) and the second high-temperature jet flame stabilizer (19) are in the closed state; when the flight Mach number is between the fifth Mach number and the sixth Mach number, the second high-temperature jet flame stabilizer (19) is in the open state, and the first high-temperature jet flame stabilizer (18) and the third high-temperature jet flame stabilizer (20) are in the closed state; when the flight Mach number is between the sixth Mach number and the second Mach number, the first high-temperature jet flame stabilizer (18) is in the open state, and the second high-temperature jet flame stabilizer (19) and the third high-temperature jet flame stabilizer (20) are in the closed state.
9. The wide-speed-range ramjet engine according to claim 8, characterized in that, The calculation formula for the activation sequence of the first high-temperature jet flame stabilizer (18), the second high-temperature jet flame stabilizer (19), and the third high-temperature jet flame stabilizer (20) is as follows: ,in, This refers to the mass flow rate of the incoming air-fuel mixture in the area in front of the tail nozzle. The average velocity of the incoming flow in the area in front of the tail nozzle. The jet mass flow rate of the high-temperature jet flame stabilizer. The jet velocity of the high-temperature jet flame stabilizer. This is an empirical constant.
10. A combined power unit, characterized in that, Including a high-speed turbine engine (3) and a wide-range ramjet engine as described in any one of claims 1-9; The combined power unit is provided with a high-speed turbine engine channel (1), and the high-speed turbine engine (3) is installed in the high-speed turbine engine channel (1); the high-speed turbine engine channel (1) and the ramming channel (2) of the wide speed range ramming engine are arranged in parallel vertically; the inlet of the high-speed turbine engine channel (1) is provided with an intake upper adjustment plate (5), and the outlet is provided with an exhaust upper adjustment plate (6).