Rotation and pulse detonation combined heat source generator and temperature distortion device

Abstract

The invention aims to solve the problem that a relatively high average temperature rise rate and a relatively high temperature transient rate are difficult to realize on an AIP surface in an existing external heat flow lead-in type temperature distortion simulator. In order to solve the problems that the cost is high and the temperature distortion index requirement is not met when an existing pulse detonation and rotating detonation combined combustion chamber is used as a heat source generator of a temperature distortion simulator, the invention provides a rotating and pulse detonation combined heat source generator and a temperature distortion device. Each combustion chamber in the heat source generator adopts a combined combustion chamber in which rotary detonation and pulse detonation are axially connected, the temperature rise value of a high-temperature area of an AIP section can be increased through continuous work of the rotary detonation, the pulse detonation only works for one cycle, the temperature rise rate of the AIP section can be greatly increased, and large pressure disturbance cannot be generated on temperature distortion simulation. After the heat source generator is adopted in the temperature distortion device, the temperature distortion device can have the advantages of an external heat flow lead-in type temperature distortion simulator and an embedded combustion type temperature distortion simulator which are commonly used at present.

Description

Technical Field

[0001] The invention belongs to the technical field of aeroengine testing, and relates to a heat source generator of a temperature distortion device and a temperature distortion device. Background Art

[0002] The types of engine intake distortion mainly include pressure distortion, temperature distortion and the combination of these two distortions. As the content of engine stability assessment becomes more and more complete, the severity of the impact of temperature distortion on the engine becomes increasingly prominent, and research on temperature distortion has also received attention and has been carried out one after another.

[0003] In order to explore the impact of temperature distortion on the engine in actual application, during the engine development and testing stage, it is necessary to simulate and test the temperature distortion of the engine in accordance with the existing intake temperature distortion assessment standards. The main objectives include: determining the critical parameters of engine inlet temperature distortion and evaluating the effectiveness and reliability of the anti-surge system.

[0004] The performance parameters of a temperature distortion simulator (also called a temperature distortion device or a temperature distortion generator) include: instantaneous temperature rise rate, average temperature rise in the high temperature zone, distortion duration, range change in the high temperature zone, temperature non-uniformity, etc. According to the different heat sources used by the temperature distortion simulator, the traditional temperature distortion simulator can be divided into an embedded combustion type and an external heat flow introduction type. Among them, the principle of the embedded combustion type temperature distortion simulator is to place the heat source generator directly upstream of the engine inlet. This type of temperature distortion simulator has the advantages of high surface average temperature rise rate and high temperature transient rate, but also has the disadvantages of complex structure, high processing cost, low test safety, and high control difficulty. The external heat flow introduction type temperature distortion simulator uses a pipeline to introduce the high-temperature working fluid flow generated externally into the aircraft engine test area, and the introduced high-temperature working fluid flow forms a temperature distortion field at the aerodynamic interface (AIP) of the aircraft engine. This type of temperature distortion simulator has the advantages of safe use and relatively simple design and manufacturing, but it also has the problem of difficulty in achieving a high average temperature rise rate and a large temperature transient rate on the AIP surface.

[0005] In order to overcome the problem that the external heat flux introduction type temperature distortion simulator is difficult to achieve a high average temperature rise rate and a large temperature transient rate on the AIP surface, Chinese patent CN118549141A proposes a temperature distortion generator with a pulse detonation and rotating detonation combined combustion chamber as a heat source generator, and the temperature distortion generator includes m independently working pulse detonation combustion chambers and n independently working rotating detonation combustion chambers. Although the high-speed high-temperature gas at the outlet of the pulse detonation combustion chamber can be transported to the AIP section in a very short time and form a huge temperature transient in the AIP section, realizing the simulation of the specified temperature rise rate of the AIP section, and the continuous high-temperature gas at the outlet of the rotating detonation combustion chamber can be used to make up for the shortcomings of the small gas flow rate and short temperature peak duration generated by the pulse detonation combustion chamber, the pressure disturbance generated by the combined combustion chamber in the patent is still high, which will have an adverse effect on the AIP section pressure parameters of the actual simulation of temperature distortion; at the same time, the temperature distortion generator requires a large space and complex adjustment method due to the use of multiple different combustion chambers and a long test section body, the space utilization rate is low, and the stability and failure rate of the coordinated work are yet to be evaluated; in addition, each combustion chamber requires an independent gas supply system, oil supply system and ignition system, and the actual application and test costs are high. Therefore, the feasibility of the temperature distortion simulator is greatly reduced.

[0006] There are other specific structures for pulse detonation and rotating detonation combined combustion chambers. After analysis, these combustion chambers cannot be used in temperature distortion generators. For example:

[0007] The pulse detonation and rotating detonation combined multi-channel combustion chamber proposed in Chinese patent application CN113932252A has a structure in which three rotating detonation combustion chambers (RDC) are nested outside one pulse detonation combustion chamber (PDC). The pulse detonation combustion chamber and the rotating detonation combustion chamber work simultaneously. Since the working pressure of the pulse detonation combustion chamber varies periodically and the pressure peak can be as high as 2-4MPa, great vibration and noise will be generated, which will have a great impact on the structural safety and reliability of the overall combined combustion chamber. At the same time, the pressure of the gas at the outlet of the pulse detonation combustion chamber is also in periodic variation, and the average pressure is also greater than 1MPa, while the pressure of the gas at the outlet of the rotating detonation combustion chamber is generally below 0.2MPa. The high-temperature combustion gas at the outlet of this pulse detonation combustion chamber will flow back into the rotating detonation combustion chamber due to the pressure difference, which will have a great adverse effect on the normal operation of the rotating detonation combustion chamber; in addition, since the three rotating detonation combustion chambers are nested outside the pulse detonation combustion chamber, the operating temperatures of both are generally more than 2000K, and the pulse detonation combustion chamber cannot be effectively cooled. Even if advanced high-temperature resistant materials are used, the practicality of this combined combustion chamber remains to be evaluated; the most important thing is that the high-temperature combustion gas generated by the combined combustion chamber will cause great pressure disturbances to the AIP section due to the periodic pressure changes of up to several MPa in the pulse detonation combustion chamber, which does not meet the index requirements of temperature distortion. Moreover, there are many practical problems, so it cannot be used in temperature distortion generators.

[0008] Chinese patent application CN118423718A proposes a pulse detonation combustion chamber based on rotating detonation wave ignition. The combustion chamber adopts a structure in which N (N≥2 and an even number) pulse detonation combustion chambers are nested outside a larger rotating detonation combustion chamber. The main source of high-temperature gas is generated by the operation of the N pulse detonation combustion chambers, while the rotating detonation combustion chamber only provides ignition for the pulse detonation combustion chamber, and the high-temperature gas generated is less. According to the working characteristics of the pulse detonation combustion chamber, the high-temperature gas generated by the pulse detonation combustion chamber is intermittent and discontinuous high-temperature gas, which is seriously inconsistent with the actual ground temperature distortion simulation reality scene, and the intermittent pressure wave peak generated by the pulse detonation combustion chamber can reach 2-4MPa, which does not meet the indicator requirement of the national aviation engine intake temperature distortion assessment standard that it cannot cause large pressure disturbances; in addition, the working temperatures in the pulse detonation combustion chamber and the rotating detonation combustion chamber are very high (usually above 2000K), and the heat dissipation problem of the pulse detonation combustion chamber in this structure is difficult to solve. Therefore, although this combined combustion chamber can improve the stability and upper limit of the operating frequency of the pulse detonation combustion chamber and only requires one ignition, its huge pressure disturbance and many problems in actual engineering applications make it impossible to apply it to temperature distortion generators. Summary of the invention

[0009] In order to solve the problem that it is difficult to achieve a high average temperature rise rate and a large temperature transient rate on the AIP surface in the existing external heat flux introduction type temperature distortion simulator, and the problem that the existing pulse detonation and rotating detonation combined combustion chamber is high in cost and does not meet the temperature distortion index requirements when used as a heat source generator for the temperature distortion simulator, the present invention proposes a rotating and pulse detonation combined heat source generator and a temperature distortion device.

[0010] The technical solution of the present invention is:

[0011] The special feature of the combined rotary and pulse detonation combustion chamber is that it includes an air inlet, a cylindrical rotary detonation combustion chamber and a straight-tube pulse detonation combustion chamber connected in sequence along the axial direction, and the rotary detonation combustion chamber and the pulse detonation combustion chamber share an air supply branch and an ignition system; the air supply branch introduces air into the cylindrical rotary detonation combustion chamber through the air inlet.

[0012] Furthermore, it also includes a first pressure sensor and a second pressure sensor, which are respectively used to detect the pressure in the oil and gas annular cavity of the rotating detonation combustion chamber and the pressure in the detonation tube of the straight tube pulse detonation combustion chamber.

[0013] Furthermore, the ignition system is a spark plug ignition, a hot jet ignition or a pre-blasting tube ignition device.

[0014] Furthermore, the pulse detonation combustion chamber is connected to the rotating detonation combustion chamber via a flange.

[0015] Furthermore, an air annular gap is provided in the middle of the front end of the rotary detonation combustion chamber, and the width of the air annular gap is determined by the air supply flow rate of the combustion chamber and the atomization and mixing effect of the fuel and air; an oil supply annular cavity and an oil-gas annular cavity are provided on the periphery of the air annular gap, and the oil-gas annular cavity is connected with the air annular gap; a fuel injection inlet connected with the oil supply annular cavity is provided on the side wall of the rotary detonation combustion chamber; a plurality of fuel nozzles distributed along the circumferential direction are provided at the bottom of the oil supply annular cavity, and the fuel nozzles are used to spray fuel into the oil-gas annular cavity; the number of fuel nozzles should ensure that the fuel has a sufficient atomization evaporation rate, ensure that the fuel and air can be fully mixed, and ensure the normal operation of the rotary detonation combustion chamber; a spark plug and at least one of the first pressure sensors are arranged on the side wall of the oil-gas annular cavity, and the spark plug extends into the oil-gas annular cavity for ignition;

[0016] The rotating detonation combustion chamber is in communication with the air inlet through the air annular gap.

[0017] Furthermore, the pulse detonation combustion chamber includes a detonation tube and a Shchelkin spiral obstacle arranged in the detonation tube; the diameter of the detonation tube is determined by the outlet of the rotating detonation combustion chamber, ensuring that the detonation tube has a sufficient distance to promote the transition from slow combustion to detonation; the Shchelkin spiral obstacle is used to promote the formation of pulse detonation waves and shorten the DDT distance; at least one of the second pressure sensors is arranged on the side wall of the detonation tube;

[0018] The inlet of the detonation tube is connected and communicated with the outlet of the rotary detonation combustion chamber through a flange; the outlet of the detonation tube is the outlet of the entire rotary and pulse detonation combined combustion chamber.

[0019] Further, it comprises an oil supply system, an air supply system, a first flow divider, a second flow divider, n independently / cooperatively working rotary and pulse detonation combined combustion chambers as described in any one of claims 1 to 6, and n ignition systems for igniting the n rotary and pulse detonation combined combustion chambers respectively;

[0020] The fuel supply system divides n fuel supply branches through the first splitter row and connects them to n rotary and pulse detonation combined combustion chambers to supply fuel to them respectively;

[0021] The air supply system divides n air supply branches through the second flow divider and connects them to n rotary and pulse detonation combined combustion chambers to provide air for them;

[0022] n is determined based on the heat source generator inlet flow parameters, the selected fuel parameters and the average temperature rise index of the maximum high temperature area of ​​the AIP surface.

[0023] Furthermore, each of the n oil supply branches is provided with an independent switch box flow meter; each of the n gas supply branches is provided with an independent switch box flow meter.

[0024] The present invention also provides a temperature distortion device, which is special in that it comprises the above-mentioned rotation and pulse detonation combined heat source generator, an air intake pile and a gas distributor;

[0025] The number of the air intake piles is equal to the number of the rotating and pulse detonation combined combustion chambers in the rotating and pulse detonation combined heat source generator, and is used to introduce the high-temperature combustion gas generated by the n rotating and pulse detonation combined combustion chambers into the gas distributor;

[0026] The gas distributor comprises a cylindrical structure with openings at both ends, and a baffle assembly arranged in the cylindrical structure; the outlet of the cylindrical structure is an AIP surface; the baffle assembly comprises a first baffle, a second baffle and a third baffle connected in sequence, the first baffle and the third baffle are symmetrical about the center of the second baffle, one side of the first baffle and the third baffle are connected to the inner wall of the cylindrical structure, and the other side is connected to the two ends of the second baffle respectively; the angle between the first baffle and the second baffle, and the angle between the third baffle and the second baffle are both obtuse angles, and the extended angle between the first baffle and the third baffle is an acute angle; the first baffle, the second baffle, the third baffle and the cylindrical structure enclose an area with a "quasi-trapezoidal" cross section; the outlet position of the baffle assembly and the length of the baffle assembly along the axial direction of the gas distributor are simulated and adjusted according to the temperature distortion index parameters of the AIP cross section to ensure that it meets the engine temperature distortion test requirements;

[0027] A single air intake pile includes a straight pipe section and a bent pipe connected in sequence; the straight pipe section is connected to the gas distributor, and the central axis of the straight pipe section and the central axis of the gas distributor are at an obtuse angle, ensuring that the high-temperature gas can flow along the main gas flow direction and will not diffuse outside the inlet of the baffle assembly; the central axis of the inlet of the bent pipe is perpendicular to the central axis of the gas distributor; the inner diameters of the straight pipe section and the bent pipe are determined by the flow formula according to the gas flow, temperature, pressure and speed of the heat source generator outlet; the outlet of the bent pipe is located in the area with the "quasi-trapezoidal" cross section;

[0028] The layout of all air intake piles meets the following requirements: with sufficient installation distance in the combustion chamber, the high-temperature gas produced by the heat source generator can be evenly distributed in the "trapezoidal" area to facilitate the mixing of the high-temperature gas with the main air flow at the inlet of the gas distributor, thereby reducing the temperature of the local hot spots in the high-temperature area of ​​the AIP surface.

[0029] The present invention also provides an engine temperature distortion simulation and testing system, which is special in that the temperature distortion device mentioned above is used to perform temperature distortion simulation.

[0030] The beneficial effects of the present invention are:

[0031] 1. Aiming at the problem of large flow engine inlet temperature distortion, the present invention optimizes the structural design of the traditional external heat flux introduction type temperature distortion simulation device, applies detonation combustion to the engine intake temperature distortion simulation, and combines the advantages of the currently commonly used external heat flux introduction type and embedded combustion type temperature distortion simulators. Through simulation, the present invention can meet the temperature distortion index requirements of the AIP section high temperature zone surface average temperature rise of 100K-300K adjustable, the high temperature zone circumferential angle less than 90°, the high temperature zone local hot spot less than 1000K and the high temperature zone temperature rise rate greater than or equal to 3000K / s.

[0032] 2. The heat source generator of the present invention only needs one set of oil supply and gas supply system to support the independent or coordinated operation of each combined combustion chamber through a bypass row, and the flow working range of each combined combustion chamber is adjustable, which greatly reduces the manufacturing and testing costs of the heat source generator and the temperature distortion simulator and greatly improves the space utilization.

[0033] 3. In the present invention, a single combined combustion chamber only needs a single ignition. The high-temperature jet generated by the rotating detonation combustion chamber in the front half promotes the formation of the pulse detonation wave in the rear half of the combustion chamber. Its high-temperature combustion gas can reach an extremely high temperature rise rate on the AIP surface. Then the rotating detonation works normally, and the high-temperature combustion gas generated can reach the average temperature rise of the high-temperature zone surface that meets the requirements on the AIP surface. Compared with other existing pulse detonation and rotating detonation combined combustion chambers, the continuous operation of the rotating detonation in the combined combustion chamber of the present invention will increase the temperature rise value of the high-temperature zone of the AIP cross section. At the same time, the pulse detonation only needs to work for one cycle, which will greatly increase the temperature rise rate of the AIP cross section and will not produce a large pressure disturbance for the temperature distortion simulation. Moreover, since the combustion chamber in the present invention is a single-channel combined combustion chamber, it does not belong to the nested combined combustion chamber structure described in Chinese patent CN118549141A and Chinese patent CN113932252A, and has good heat dissipation performance, so no cooling system is required. At the same time, it also avoids the adverse effects caused by the vibration of the nested combined combustion chamber, and its safety and reliability are greatly improved.

[0034] 4. The gas distributor in the present invention is provided with a baffle assembly to form a flow channel with a "quasi-trapezoidal" cross-section, which gathers high-temperature gas in the flow channel, and can form a circumferential range of a high-temperature zone not exceeding 90° in the AIP section, meeting the temperature distortion index requirements. At the same time, since the extension direction of the baffle assembly is parallel to the mainstream air direction of the gas distributor inlet, the windward area of ​​the baffle assembly is greatly reduced, and it has the characteristics of small flow resistance and low total pressure loss. In addition, compared with the existing temperature distortion simulator that usually requires a gas distributor length of 2m-5m, the present invention uses a combined rotation and pulse detonation combustion chamber as a heat source generator, and utilizes the advantages of detonation combustion to generate high-temperature and high-pressure gas, thereby reducing the size and number of combustion chambers and the space required for the combustion chamber arrangement. Therefore, the length of the gas distributor can be less than 1.5m, which greatly improves the space utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a triaxial diagram of the temperature distortion device of the present invention.

[0036] Figure 2 It is a top view of the temperature distortion device of the present invention.

[0037] Figure 3It is a schematic diagram of the structure of a single rotating and pulse detonation combined combustion chamber in the present invention, wherein Figure (a) is a top view and Figure (b) is an EE cross-sectional view in Figure (a).

[0038] Figure 4 It is a schematic structural diagram of a single rotating and pulse detonation combined combustion chamber head in the present invention, wherein Figure (a) is a stereoscopic diagram and Figure b is a side view.

[0039] Figure 5 The structure diagram of the gas distributor and the gas inlet pile after assembly in the temperature distortion device of the present invention is shown in FIG. Figure 1 , where Figure (a) is the left view and Figure (b) is the front view.

[0040] Figure 6 The structure diagram of the gas distributor and the air intake assembly in the temperature distortion device of the present invention after assembly Figure 2 (Another perspective), wherein Figure (a) is a top view, and Figure (b) is an EE cross-sectional view in Figure a.

[0041] Figure 7 The invention is a schematic diagram of the principle of an engine temperature distortion simulation and test system composed of the temperature distortion device of the invention and the existing control console, oil supply system, air supply system, oxygen supplementation system and measurement system.

[0042] Figure 8 It is a dot-line diagram of the average temperature of the high temperature zone of the AIP section and the circumferential angle of the high temperature zone under different working conditions.

[0043] Fig. 9 It is the working conditions corresponding to different temperature rise values ​​in the high temperature zone and the simulation parameter diagram of the corresponding working conditions

[0044] Fig.10 It is the AIP section temperature cloud diagram corresponding to the working conditions of different temperature rise values ​​in the high temperature zone.

[0045] Fig.11 It is a dot-line diagram of the average temperature and temperature rise rate in the high temperature zone at different axial positions of the gas distributor under working condition 1.

[0046] Reference numerals:

[0047] 1. Air inlet; 2. Fuel injection inlet; 3. Air annular gap, 4. Fuel supply annular cavity, 5. Fuel nozzle; 6. Spark plug; 7. First pressure sensor; 8. Shchelkin spiral obstacle; 9. Rotating detonation combustion chamber; 10. Pulse detonation combustion chamber; 11. Outlet of combined combustion chamber; 12. Intake pile; 13. Baffle assembly; 14. Gas distributor; 15. Gas distributor inlet; 16. Gas distributor outlet; 17-Second pressure sensor; 18-First flange; 19-Second flange; 20-Third flange; 21-Fourth flange; 22-Oil and gas annular cavity; 23-Cylindrical structure; 24-Fifth flange. DETAILED DESCRIPTION

[0048] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and numerical simulation verification.

[0049] Embodiment 1:

[0050] like Figure 1-4 As shown in , 7 , this embodiment provides a temperature distortion device, including a heat source generator, an air intake pile 12 and a gas distributor 14 .

[0051] The heat source generator includes an oil supply system, an air supply system, a first flow divider, a second flow divider, three independent / cooperative rotary and pulse detonation combined combustion chambers, and three ignition systems. The oil supply system divides three oil supply branches through the first flow divider (each oil supply branch is provided with an independent switch and flow meter) and is respectively connected to the three rotary and pulse detonation combined combustion chambers to provide fuel for them. The air supply system divides three air supply branches through the second flow divider (each air supply branch is provided with an independent switch and flow meter) and is respectively connected to the three rotary and pulse detonation combined combustion chambers to provide air for them. In other embodiments, the number of rotary and pulse detonation combined combustion chambers is not necessarily three, and its specific number is determined according to the heat source generator inlet flow parameter, the selected fuel parameter and the average temperature rise index of the maximum high temperature zone of the AIP surface.

[0052] The single rotary and pulse detonation combined combustion chamber is a single-channel detonation combustion chamber, including an air inlet 1, a cylindrical rotary detonation combustion chamber 9 and a straight-tube pulse detonation combustion chamber 10 connected in sequence along the axial direction. The rotary detonation combustion chamber 9 and the pulse detonation combustion chamber 10 share an air supply branch and an ignition system.

[0053] The air inlet 1 is arranged at the head of the rotating detonation combustion chamber 9 and is connected to the rotating detonation combustion chamber 9. The air inlet 1 should adopt a larger pipe diameter (diameter is 50mm-80mm) to ensure that a larger air supply flow rate can flow. The air supply flow rate should be determined according to the air flow rate required by the engine temperature distortion test.

[0054] An air annular gap 3 is provided in the middle of the front end of the rotary detonation combustion chamber 9. The width of the air annular gap 3 is 2mm-4mm. The specific value is determined by the air supply flow rate of the combustion chamber and the atomization and mixing effect of the fuel and air. The air annular gap 3 is connected to the air inlet 1; an oil supply annular cavity 4 and an oil-gas annular cavity 22 are provided on the periphery of the air annular gap 3, and the oil-gas annular cavity is connected to the air annular gap 3; a fuel injection inlet 2 is provided on the side wall of the rotary detonation combustion chamber 9, and the fuel injection inlet 2 is connected to the oil supply annular cavity 4; a plurality of circumferentially distributed Fuel nozzles 5, these fuel nozzles 5 are used to spray fuel into the oil-gas annular cavity; the number of fuel nozzles 5 should ensure that the fuel has sufficient atomization evaporation rate, ensure that the fuel and air can be fully mixed, and ensure the normal operation of the rotating detonation combustion chamber 9; the side wall of the oil-gas annular cavity 22 is provided with a spark plug 6 and at least one first pressure sensor 7, the spark plug 6 extends into the oil-gas annular cavity 22 for ignition, and the first pressure sensor 7 is used to detect the pressure in the oil-gas annular cavity to determine whether the detonation wave is formed and whether the rotating detonation combustion chamber 9 is operating normally. When there are multiple first pressure sensors 7, these multiple first pressure sensors 7 are evenly arranged along the circumference. In other embodiments, the spark plug 6 can also be replaced with a hot jet ignition or a pre-detonation tube ignition device to improve the ignition success rate. The outlet of the rotating detonation combustion chamber 9 is provided with a first flange 18 for connecting with the second flange 19 at the entrance of the pulse detonation combustion chamber 10.

[0055] The pulse detonation combustion chamber 10 includes a detonation tube and a Shchelkin spiral obstacle 8 arranged in the detonation tube. The diameter of the detonation tube is determined by the outlet of the rotating detonation combustion chamber. The aspect ratio should be greater than 10 to ensure that the detonation tube has enough distance to promote the transition from slow combustion to detonation. The Shchelkin spiral obstacle 8 is used to promote the formation of pulse detonation waves and shorten the DDT distance. At least one second pressure sensor 17 is arranged on the side wall of the detonation tube to detect the pressure in the detonation tube to determine whether the detonation wave is formed and whether the pulse detonation combustion chamber 10 is working normally. When there are multiple second pressure sensors 17, these multiple second pressure sensors 17 are evenly arranged along the circumference of the detonation tube. The inlet of the detonation tube is provided with a second flange 19, and the outlet is provided with a third flange 20, which are respectively used to connect with the first flange 18 at the outlet of the rotating detonation combustion chamber 9 and the fourth flange 21 at the inlet of the air intake pile 12. The outlet of the detonation tube is the outlet 11 of the entire rotating and pulse detonation combined combustion chamber.

[0056] The wall thickness of the rotating detonation combustion chamber 9 and the pulse detonation combustion chamber 10 should be greater than 10 mm to ensure that the combustion chamber will not melt or deform under high temperature working environment.

[0057] The fuel provided by the external fuel supply system enters the fuel supply annular cavity 4 at the head of the rotating detonation combustion chamber 9 from the fuel injection inlet 2, and is then sprayed into the oil-gas annular cavity 22 by the fuel nozzle 5; the air enters the air annular gap 3 of the rotating detonation combustion chamber 9 from the air inlet 1, expands and accelerates, and then enters the oil-gas annular cavity 22 to be fully mixed with the fuel therein. The fuel supply pressure of the external fuel supply system should be greater than 2MPa to ensure that the fuel can be continuously supplied under the normal operation of the rotating detonation combustion chamber 9. Pressure sensors 7 are arranged circumferentially and axially on the outer surface of the combustion chamber to monitor whether the detonation wave in the combustion chamber is formed and whether it is working normally.

[0058] There are three air intake piles 12, which are arranged in an isosceles triangle and arranged on the outer surface of the gas distributor 14, and are respectively used to connect and communicate the outlets of the three rotary and pulse detonation combined combustion chambers with the gas distributor 14, so as to respectively introduce the high-temperature gas generated by the three rotary and pulse detonation combined combustion chambers into the "quasi-trapezoidal" cross-section area of ​​the gas distributor 14. This isosceles triangle layout can fully distribute the high-temperature gas generated by the heat source generator in the entire "quasi-trapezoidal" area while ensuring that the combustion chamber has sufficient installation distance, which is conducive to the mixing of the high-temperature gas with the main air flow at the inlet of the gas distributor, thereby reducing the temperature of the local hot spot in the high-temperature area of ​​the AIP surface. Secondly, this isosceles triangle layout can reduce the distance between the air intake pile farthest from the inlet of the gas distributor and the inlet of the gas distributor, so that the high-temperature gas and the main air flow are mixed at the shortest distance, thereby reducing the length of the entire gas distributor and improving the compactness of the structure. If the number of air intake piles is greater than three, the layout of the air intake piles should ensure that there is sufficient installation distance between the combustion chambers, so that the high-temperature fuel gas generated by the heat source generator can be fully and evenly distributed in the entire "trapezoidal" area as much as possible, which is conducive to the mixing of the high-temperature fuel gas with the main air flow at the inlet of the gas distributor, thereby reducing the temperature of the local hot spots in the high-temperature area of ​​the AIP surface.

[0059] like Figure 5 and Figure 6As shown, a single air intake pile 12 is composed of a straight pipe section, a bend pipe and a fourth flange connected in sequence. The straight pipe section is connected to the gas distributor 14, and the angle between the central axis of the straight pipe section and the central axis of the gas distributor is an obtuse angle, which ensures that the high-temperature gas can flow along the main airflow direction and will not diffuse outside the inlet of the baffle assembly 13. On the one hand, it can reduce the pressure loss caused by the intersection of the high-temperature gas and the main airflow, and on the other hand, it can avoid the vibration caused by the high-temperature gas impacting the baffle assembly 13 in the gas distributor 14 and the problem of excessive circumferential angle of the high-temperature zone. There is no special requirement for the length of the straight pipe section. The central axis of the bend pipe at the inlet should be perpendicular to the central axis of the gas distributor 14, so the angle of the bend pipe is determined by the angle between the central axis of the straight pipe section and the gas distributor 14, and there is no special requirement for the length of the bend pipe section. The fourth flange is used to connect and communicate the bend pipe section with the outlet of the pulse detonation combustion chamber 10. The inner diameter of the air intake pile 12 (including straight pipes and curved pipes) is determined by the flow formula known in the art according to the gas flow, temperature, pressure and speed at the outlet of the heat source generator. The wall thickness of the air intake pile 12 should be greater than 5 mm to ensure that it can withstand high temperatures above 2000K. The parameters of the fourth flange of the air intake pile 12 should be consistent with the parameters of the third flange at the outlet of the pulse detonation combustion chamber 10, and the national standard flange should be used for connection. The distance between the center lines of two adjacent air intake piles 12 should be determined based on the maximum circumferential distance of a single rotating and pulse detonation combined combustion chamber in the heat source generator and leave surplus space to ensure that the heat source generator can be installed normally.

[0060] like Figure 1 , 5-6, the gas distributor 14 is composed of a cylindrical structure 23 with two ends open, a baffle assembly 13 arranged in the cylindrical structure, and a fifth flange 24 arranged at both ends of the cylindrical structure. The fifth flange 24 at the inlet of the gas distributor 14 is used to connect the engine inlet gas source to realize the temperature distortion function, or to connect the pressure distortion device in combination to realize more functions. The outlet of the gas distributor 14 is an AIP surface. The baffle assembly 13 includes a first baffle, a second baffle and a third baffle connected in sequence. The first baffle and the third baffle are symmetrical about the center of the second baffle. One side of the first baffle and the third baffle are connected to the inner wall of the cylindrical structure, and the other side is connected to the two ends of the second baffle respectively; the angle between the first baffle and the second baffle, and the angle between the third baffle and the second baffle are both obtuse angles, and the extended angle between the first baffle and the third baffle is an acute angle; the first baffle, the second baffle, the third baffle and the cylindrical structure 23 enclose an area with a "quasi-trapezoidal" cross section. The length of the baffle assembly 13 along the axial direction of the cylindrical structure 23 should include the outlet of the air intake pile 12 on the gas distributor 14, so as to ensure that the high-temperature gas output by the heat source generator is introduced into the cylindrical structure 23 through the air intake pile 12, and is gathered in the area with a "quasi-trapezoidal" cross section, forming a high-temperature zone range required by the engine temperature distortion test on the AIP surface. The outlet position of the baffle assembly 13 (i.e., the cutoff position of the area with a "quasi-trapezoidal" cross section) and the length of the baffle assembly 13 along the axial direction of the gas distributor 14 should be adjusted by simulation according to the temperature distortion index parameters of the AIP cross section to ensure that it meets the requirements of the engine temperature distortion test. The thickness of each baffle in the baffle assembly 13 should be as small as possible while being able to withstand the high-speed impact of high-temperature gas, so as to avoid generating an excessively large frontal area and causing a large pressure loss. The length of the gas distributor 14 should be determined by simulation according to the engine temperature distortion test requirements and the temperature rise value, temperature rise rate, circumferential angle range and local hot spot index parameters of the high-temperature zone of the temperature distortion AIP cross section.

[0061] During the design, this embodiment can adjust the number of rotating and pulse detonation combined combustion chambers in the heat source generator, and adjust the working flow rate of the rotating and pulse detonation combined combustion chambers. According to the temperature rise value, temperature rise rate, circumferential angle range and local hot spot parameters of the temperature distortion high temperature zone, numerical simulation is performed to determine the structural parameters of the gas distributor 14 and the baffle assembly 13, so as to obtain the optimal temperature distortion device structure, and ensure that the designed temperature distortion device can produce an intake temperature distortion simulation that meets the requirements of adjustable temperature rise in the high temperature zone of the AIP section, circumferential angle range, temperature rise rate and local hot spot by adjusting the working number and working flow rate of the rotating and pulse detonation combined combustion chambers in the heat source generator.

[0062] The working principle of this embodiment and the method of generating temperature distortion are as follows:

[0063] In view of the requirements of the temperature rise index of the intake temperature distortion of large-flow aircraft engines, thermodynamic calculations are carried out to determine the air supply flow range and the fuel supply flow range that need to be provided to the heat source generator. Then, based on the calculated air supply flow range and fuel supply flow range, air and fuel enter from the air inlet 1 and the fuel injection inlet 2 respectively, the air expands and accelerates through the air annular gap 3, the fuel passes through the fuel supply ring cavity 4 and is atomized and evaporated through the fuel nozzle 5, and is fully mixed with the air in the oil and gas ring cavity 22 to form a uniformly mixed combustible gas. After the combustible gas fills the entire oil and gas annular cavity 22 and the detonation tube of the pulse detonation combustion chamber 9, the spark plug 6 installed at the head of the rotating detonation combustion chamber 9 is ignited, and the flame jet generated by the rotating detonation combustion chamber 9 enters the detonation tube of the pulse detonation combustion chamber 10, contacts the fresh combustible mixture in the detonation tube and promotes the formation of the pulse detonation wave through the Shchelkin spiral obstacle 8. The pulse detonation only works for one cycle, and then the rotating detonation works normally (during this period, the pulse detonation combustion chamber is used to transmit the high-temperature combustion gas generated by the rotating detonation). The high-temperature combustion gas generated by the rotating detonation enters the air intake pile 12 through the outlet 11 of the combined combustion chamber.

[0064] The high-temperature combustion gas passes through the bend of the air inlet pile 12 to mix with the main airflow at the gas distributor inlet 15 at a certain axial angle and converges in an area with a "trapezoidal" cross-section enclosed by the baffle assembly 13 and the cylindrical structure 23. Then, the high-temperature mixed airflow begins to diffuse through the outlet of the baffle assembly 13 and generates temperature distortion on the AIP section of the gas distributor outlet 16.

[0065] Simulation verification and analysis:

[0066] The design index requirements of the temperature distortion device of this embodiment are as follows: the average temperature rise of the high temperature zone of the engine AIP section is adjustable from 100K to 300K, the circumferential angle of the high temperature zone is less than 90°, the local hot spot in the high temperature zone is less than 1000K, and the temperature rise rate in the high temperature zone is greater than or equal to 3000K / s.

[0067] The specific structural parameters of the temperature distortion device of this embodiment are as follows:

[0068] The inner diameter of the gas distributor 14 is 750mm and the length is 1500mm. The front end of the baffle assembly 13 is located 100mm from the inlet of the gas distributor, and the length along the axial direction of the gas distributor is 700mm. The angle between the first baffle and the second baffle, and the angle between the third baffle and the second baffle are both 130 degrees. The length of the second baffle is 276mm, and the distance between the second baffle and the central axis of the gas distributor is 164mm. The inner diameters of air intake pile No. 1 and air intake pile No. 2 are 95mm, the inner diameter of air intake pile No. 3 is 110mm, and the angles between the three air intake piles and the central axis of the gas distributor are all 60°. The total operating flow range of the heat source generator is 0.7kg / s to 3.4kg / s. According to the operating flow range and the temperature rise in the high temperature zone of the AIP section, a total of 18 working conditions are summarized for simulation, as shown in Table 1 (the unit of the air intake pile flow in the table is Kg / s):

[0069] Table 1 Gas flow under different schemes and different working conditions

[0070]

[0071] Simulation results analysis:

[0072] like Figure 8As shown in the figure, it is a dot-line diagram of the average temperature rise and circumferential angle of the high temperature zone of the AIP section at 1.45m along the axial direction from the gas distributor inlet under different flow conditions. Under working conditions 1, 2 and 3, the heat source generator uses a combined combustion chamber to work, and uses air intake pile No. 1 to introduce high temperature gas into the gas distributor. As the working flow of a single combined combustion chamber increases, the average temperature rise of the high temperature zone decreases instead. This is because as the flow rate increases, the high temperature gas is mixed more evenly with the inlet main airflow, and the circumferential angle of the high temperature zone gradually increases, resulting in a gradual increase in the area of ​​high temperature gas diffusion, which leads to a decrease in the average temperature rise of the high temperature zone. Under working conditions 4, 5, and 6, the heat source generator also uses a combined combustion chamber to work, and the working flow range is consistent with working conditions 1, 2, and 3, but the air intake pile No. 2 is used to introduce the high temperature gas into the gas distributor. Compared with air intake pile No. 1, air intake pile No. 2 is closer to the AIP section, and the diffusion range of high temperature gas is smaller, which leads to a smaller circumferential angle of the high temperature zone and a larger average temperature rise. Under working conditions 7, 8, and 9, the heat source generator also uses a combined combustion chamber to work, but the air intake pile No. 3 is used to introduce the high-temperature gas into the gas distributor, and the working flow of the combined combustion chamber is increased from 0.7kg / s to 1kg / s to 1.4kg / s compared with working conditions 1 to 6. With the increase of working flow, the average temperature rise of the high-temperature zone of the AIP section gradually increases, and the overall average temperature rise is between working conditions 1 to 3 and working conditions 4 to 6. This is because the air intake pile No. 3 is close to the baffle wall, and the high-temperature gas flow of the combined combustion chamber increases, which impacts the baffle and causes the high-temperature gas to diffuse in a larger range. The circumferential angle of the high-temperature zone is always at 100° to 110°, so compared with working conditions 1 to 6, the working flow of the combined combustion chamber increases, but the average temperature rise of the high-temperature zone decreases. For working conditions 10 to 15, the heat source generator uses two combined combustion chambers to work. With the increase of working flow, the average temperature of its high-temperature zone gradually increases, and the circumferential angle of the high-temperature zone hovers around 90°. Working conditions 16 to 18 are for the operation of three combustion chambers. It can be seen that with the increase of working flow, the high-temperature combustion gas is mixed more evenly with the inlet main airflow, the average temperature of the high-temperature zone of the AIP section gradually increases, and the degree of diffusion basically tends to be stable. The circumferential angle of the high-temperature zone is always stable below 90°.

[0073] like Fig. 9 As shown, from the simulation of different working conditions, working conditions and simulation parameters of corresponding working conditions that meet the requirements of adjustable average temperature rise in the high temperature zone of 100K to 300K and temperature distortion index with a circumferential angle range of less than 90° were obtained.

[0074] like Fig.10 As shown, the corresponding Fig. 9The high temperature area cloud map of the AIP section at 1.45m axially away from the gas distributor inlet in the operating condition shows that the circumferential angle range of the high temperature zone is always within the fan-shaped range of 90 degrees, and the temperature of the highest point in the high temperature zone is always below 1000K, which meets the index requirement of temperature distortion for local hot spots less than 1000K, avoiding burning of the engine compressor blades.

[0075] like Fig.11 As shown, the average temperature and temperature rise rate of the high temperature zone at different axial positions of the gas distributor under the lowest working flow condition 1. It can be seen that with the increase of the axial distance from the hot gas distributor inlet, the average temperature of the high temperature zone gradually decreases, and the temperature rise rate also gradually decreases. This is because with the increase of the axial distance, the high temperature gas is not bound by the baffle assembly 13, the diffusion range gradually increases, and the local hot spots gradually decrease, so the temperature and temperature rise rate of the high temperature zone will decrease. However, at the AIP section 1.45m away from the gas distributor inlet, the temperature rise rate of the AIP section also meets the temperature distortion index requirement for a temperature rise rate greater than or equal to 3000K / s.

[0076] It can be seen from the above simulation results that the temperature distortion device of this embodiment is feasible in terms of theory, simulation and practicality.

[0077] Embodiment 2:

[0078] The heat source generator in the present invention has an independent function, can provide high-temperature gas that meets specific requirements, and can be sold separately, which can meet the use requirements when the heat source generator in the temperature distortion device fails and needs to be replaced. Therefore, this embodiment provides a heat source generator, and its structure and principle are the same as those of the heat source generator in Example 1, which will not be repeated here.

[0079] Embodiment 3:

[0080] The rotary and pulse detonation combined combustion chamber in the present invention has independent functions, can provide high-temperature combustion gas that meets specific requirements, and can be sold separately, which can meet the use requirements when a single or multiple rotary and pulse detonation combined combustion chambers in the temperature distortion device fail and need to be replaced. Therefore, this embodiment provides a rotary and pulse detonation combined combustion chamber, and its structure and principle are the same as those of the rotary and pulse detonation combined combustion chamber in Example 1, which will not be repeated here.

[0081] Embodiment 4:

[0082] like Figure 7As shown, this embodiment provides an engine temperature distortion simulation and test system, including a control console, an oxygen supplementation system, a temperature distortion device, a test section and a measurement system. Among them, the temperature distortion device adopts the temperature distortion device provided in Example 1, and the control console, the oxygen supplementation system, the test section and the measurement system are all existing units. The oxygen supplementation system can adjust the oxygen content percentage of oxygen-enriched air through flow regulation, and its branch outlet position is located on the air main flow channel diversion row. The test section includes an AIP cross-sectional section where temperature and pressure sensors are assembled and the entire engine for subsequent testing. The measurement system includes a temperature and pressure measurement rake at the engine inlet. The control console sends control signals to the oil system, the oxygen supplementation system and the air system, and receives measurement signals from the measurement system at the same time.

Claims

1. A combined combustion chamber of rotating and pulse detonation, characterized in that: It comprises an air inlet, a cylindrical rotating detonation combustion chamber and a straight-tube pulse detonation combustion chamber which are sequentially connected along the axial direction. The rotating detonation combustion chamber and the pulse detonation combustion chamber share an air supply branch and an ignition system. The air supply branch introduces air into the cylindrical rotating detonation combustion chamber through the air inlet.

2. The combined rotating and pulse detonation combustion chamber according to claim 1, characterized in that: It also includes a first pressure sensor and a second pressure sensor, which are respectively used to detect the pressure in the oil and gas annular cavity of the rotating detonation combustion chamber and the pressure in the detonation tube of the straight tube pulse detonation combustion chamber.

3. The combined rotating and pulse detonation combustion chamber according to claim 1 or 2, characterized in that: The ignition system is a spark plug ignition, a hot jet ignition or a pre-squib ignition device.

4. The combined rotating and pulse detonation combustion chamber according to claim 3, characterized in that: The pulse detonation combustion chamber is connected to the rotating detonation combustion chamber via a flange.

5. The combined rotating and pulse detonation combustion chamber according to claim 4, characterized in that: An air ring gap is provided at the middle of the front end of the rotating detonation combustion chamber, and the width of the air ring gap is determined by the air supply flow rate of the combustion chamber and the atomization and mixing effect of the fuel and air; an oil supply ring cavity and an oil-gas ring cavity are provided on the periphery of the air ring gap, and the oil-gas ring cavity is connected with the air ring gap; a fuel injection inlet connected with the oil supply ring cavity is provided on the side wall of the rotating detonation combustion chamber; a plurality of fuel nozzles distributed along the circumferential direction are provided at the bottom of the oil supply ring cavity, and the fuel nozzles are used to spray fuel into the oil-gas ring cavity; the number of fuel nozzles should ensure that the fuel has a sufficient atomization evaporation rate, ensure that the fuel and air can be fully mixed, and ensure the normal operation of the rotating detonation combustion chamber; a spark plug and at least one of the first pressure sensors are arranged on the side wall of the oil-gas ring cavity, and the spark plug extends into the oil-gas ring cavity for ignition; The rotating detonation combustion chamber is in communication with the air inlet through the air annular gap.

6. The combined rotating and pulse detonation combustion chamber according to claim 5, characterized in that: The pulse detonation combustion chamber includes a detonation tube and a Shchelkin spiral obstacle arranged in the detonation tube; the diameter of the detonation tube is determined by the outlet of the rotating detonation combustion chamber, ensuring that the detonation tube has a sufficient distance to promote the transition from slow combustion to detonation; the Shchelkin spiral obstacle is used to promote the formation of pulse detonation waves and shorten the DDT distance; at least one of the second pressure sensors is arranged on the side wall of the detonation tube; The inlet of the detonation tube is connected and communicated with the outlet of the rotary detonation combustion chamber through a flange; the outlet of the detonation tube is the outlet of the entire rotary and pulse detonation combined combustion chamber.

7. Rotation and pulse detonation combined heat source generator, characterized in that: It comprises an oil supply system, an air supply system, a first flow distribution row, a second flow distribution row, n independently / cooperatively working rotary and pulse detonation combined combustion chambers as described in any one of claims 1 to 6, and n ignition systems for igniting the n rotary and pulse detonation combined combustion chambers respectively; The fuel supply system divides n fuel supply branches through the first splitter row and connects them to n rotary and pulse detonation combined combustion chambers to supply fuel to them respectively; The air supply system divides n air supply branches through the second flow divider and connects them to n rotary and pulse detonation combined combustion chambers to provide air for them; n is determined based on the heat source generator inlet flow parameters, the selected fuel parameters and the average temperature rise index of the maximum high temperature area of ​​the AIP surface.

8. The combined rotary and pulse detonation heat source generator according to claim 7 is characterized in that: Each of the n oil supply branches is equipped with an independent switch box flow meter; each of the n gas supply branches is equipped with an independent switch box flow meter.

9. Temperature distortion device, characterized in that: It comprises the combined rotary and pulse detonation heat source generator, air intake pile and gas distributor as described in claim 7 or 8; The number of the air intake piles is equal to the number of the rotating and pulse detonation combined combustion chambers in the rotating and pulse detonation combined heat source generator, and is used to introduce the high-temperature combustion gas generated by the n rotating and pulse detonation combined combustion chambers into the gas distributor; The gas distributor comprises a cylindrical structure with openings at both ends, and a baffle assembly arranged in the cylindrical structure; the outlet of the cylindrical structure is an AIP surface; the baffle assembly comprises a first baffle, a second baffle and a third baffle connected in sequence, the first baffle and the third baffle are symmetrical about the center of the second baffle, one side of the first baffle and the third baffle are connected to the inner wall of the cylindrical structure, and the other side is connected to the two ends of the second baffle respectively; the angle between the first baffle and the second baffle, and the angle between the third baffle and the second baffle are both obtuse angles, and the extended angle between the first baffle and the third baffle is an acute angle; the first baffle, the second baffle, the third baffle and the cylindrical structure enclose an area with a "quasi-trapezoidal" cross section; the outlet position of the baffle assembly and the length of the baffle assembly along the axial direction of the gas distributor are simulated and adjusted according to the temperature distortion index parameters of the AIP cross section to ensure that it meets the requirements of the engine temperature distortion test; A single air intake pile includes a straight pipe section and a bent pipe connected in sequence; the straight pipe section is connected to the gas distributor, and the central axis of the straight pipe section and the central axis of the gas distributor are at an obtuse angle, ensuring that the high-temperature gas can flow along the main gas flow direction and will not diffuse outside the inlet of the baffle assembly; the central axis of the inlet of the bent pipe is perpendicular to the central axis of the gas distributor; the inner diameters of the straight pipe section and the bent pipe are determined by the flow formula according to the gas flow, temperature, pressure and speed at the outlet of the heat source generator; the outlet of the bent pipe is located in the area with a "quasi-trapezoidal" cross section; The layout of all air intake piles meets the following requirements: with sufficient installation distance in the combustion chamber, the high-temperature gas generated by the heat source generator can be evenly distributed in the "trapezoidal" area to facilitate the mixing of the high-temperature gas with the main air flow at the inlet of the gas distributor, thereby reducing the temperature of the local hot spots in the high-temperature area of ​​the AIP surface. 10.Engine temperature distortion simulation and testing system, characterized by: The temperature distortion device described in claim 9 is used to perform temperature distortion simulation.

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