Rotating detonation combustion chamber inner cylinder end face pressure testing device

Abstract

The application provides a rotating detonation combustion chamber inner cylinder end face pressure testing device under axial air inlet and radial air inlet conditions, which comprises an end cover (1), an inner cylinder (2), an axial air inlet outer cylinder (3), a connecting sheet (4), an adapter section (5), a pressure measuring tube (6), a blind plate (7) and a radial air inlet outer cylinder (8); the end cover (1), the inner cylinder (2) and the stainless steel pressure measuring tube (6) are common structures, the axial air inlet outer cylinder (3), the connecting sheet (4) and the adapter section (5) are structures used under axial air inlet conditions, and the blind plate (7) and the radial air inlet outer cylinder (8) are structures used under radial air inlet conditions. The end cover is provided with a static pressure measuring point, and the pressure is led out through the stainless steel pressure measuring tube (6) for measurement. The end face static pressure value can be obtained under the condition of not affecting the tail flow field, and the bottom resistance is calculated.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aero-engines, and particularly relates to a rotating detonation combustion chamber inner cylinder end face pressure testing device under axial air intake and radial air intake conditions. BACKGROUND

[0002] At present, the development of traditional aero-engines adopting the Brayton cycle has entered a "bottleneck", and the space for performance improvement is already small. The detonation engine has the advantages of self-pressurization, high cycle efficiency, small entropy increase and fast heat release rate in theory due to the adoption of a new thermodynamic cycle and the conversion of the combustion mode from slow combustion to detonation combustion, and can significantly improve the overall performance of the aero-engine.

[0003] The rotating detonation engine is one of the engines mainly adopting detonation combustion, and the combustion chamber thereof is mostly annular and composed of an outer cylinder and an inner cylinder. Fresh reactants are continuously supplied from the head of the combustion chamber, ignited by an ignition device after mixing for a distance, and form a single or multiple detonation wave heads moving in the circumferential direction in the annular passage. The reactants are consumed by the wave heads to form high-enthalpy combustion products, which are discharged at high speed through the combustion chamber outlet or nozzle, thereby generating thrust.

[0004] However, the performance advantages of the rotating detonation engine have not been fully developed. Although there is a positive total pressure gain in theory, there is no corresponding experimental result in the international community. In order to accurately measure the total pressure gain of the rotating detonation engine, the equivalent available pressure method (EAP) is used, and the core is to obtain the actual thrust of the engine. Due to the adoption of the annular structure, the entrainment of the wake will generate a negative pressure area at the end face of the inner cylinder, thereby generating resistance, which accounts for about 10-20% of the measured thrust value. In order to obtain the bottom resistance value, the pressure distribution at the end face of the inner cylinder must be measured. SUMMARY

[0005] The application provides a rotating detonation combustion chamber inner cylinder end face pressure testing device, which comprises an end cover 1, an inner cylinder 2, an axial air intake outer cylinder 3, a connecting piece 4, an adapter section 5, a pressure measuring pipe 6, a blind plate 7 and a radial air intake outer cylinder 8; the end cover 1, the inner cylinder 2 and the stainless steel pressure measuring pipe 6 are common structures, the axial air intake outer cylinder 3, the connecting piece 4 and the adapter section 5 are structures used under the axial air intake condition, and the blind plate 7 and the radial air intake outer cylinder 8 are structures used under the radial air intake condition; wherein

[0006] 1) an inner cylinder end face pressure testing device under the axial air intake condition;

[0007] The end cover 1 is a disc structure with a certain thickness, and a plurality of semi-head through holes are uniformly arranged near the outer periphery in the circumferential direction, and a plurality of pressure measuring holes are arranged along one radius direction of the disc; the positional relationship between the pressure measuring holes and the semi-head through holes is fixed;

[0008] The inner cylinder 2 is a hollow cylinder as a whole, and a throat is arranged at the middle left position and extends outward in the radial direction. The cross-sectional shape of the throat is an isosceles trapezoid without a bottom side, and the upper base of the trapezoid is smaller than the lower base. The lower base is on the outer surface of the hollow cylinder of the inner cylinder 2. The inner cylinder 2 is coaxially connected with the end cover 1, and a plurality of bosses are arranged on the inner wall surface at the position close to the right outlet. Threaded holes are arranged on the bosses, and the positions of the threaded holes are the same as those of the semi-head through holes on the end cover. Semi-head screws connect the inner cylinder 2 and the end cover 1 from right to left, so as to ensure that the right plane of the end cover coincides with the right end surface of the inner cylinder 2. An inner flange is arranged on the left end surface of the inner cylinder 2, and an annular groove and a plurality of through holes parallel to the axial direction of the device are arranged on the inner flange. The center of the annular groove is on the axis of the device, and the through holes are inside the annular groove.

[0009] The axial air inlet outer cylinder 3 is a hollow cylinder as a whole, and an outer flange is arranged on the left end surface. An annular groove and a plurality of through holes parallel to the axial direction of the device are arranged on the outer flange. The inner cylinder 2 and the axial air inlet outer cylinder 3 are coaxial, and the left and right end surfaces are flush.

[0010] The connecting piece 4 is arranged in front of the inner cylinder 2 and the axial air inlet outer cylinder 3, and is a hollow annular structure as a whole, including concentric inner and outer rings. The center of the connecting piece 4 is on the axis of the device, and the inner and outer rings are connected by a plurality of uniformly arranged rib plates. A plurality of through holes are arranged on the inner and outer rings, and the number of through holes on the inner and outer rings is the same. An annular groove is arranged on the right side of the inner and outer rings respectively, and the annular grooves are concentric. The annular groove and the through hole on the right side of the inner ring correspond to the annular groove and the through hole arranged on the left end surface of the inner cylinder 2 in terms of position, shape and size. The annular groove and the through hole on the right side of the outer ring correspond to the annular groove and the through hole arranged on the left end surface of the axial air inlet outer cylinder 3 in terms of position, shape and size. The inner ring is coaxially connected with the inner cylinder 2 by a fixing mechanism. Two concentric annular bosses are arranged on the left end surfaces of the inner and outer rings respectively, and the center of the annular boss is on the axis of the device.

[0011] The transition section 5 is a hollow cylinder, comprising, from right to left: an outer flange with an inner ring, a hollow cylindrical section, a hollow frustum section, and an international flange; the outer flange with an inner ring is connected to the outer flange by multiple evenly distributed ribs, the shape and size of which are exactly the same as those in the connecting piece 4; an annular groove is arranged on the right end face of the outer flange, and multiple through holes parallel to the axial direction of the device are provided; the inner ring is a hollow cylinder with a bottom, the bottom being annular, and a through hole at the center of the bottom of the annular ring; the inner ring, ribs, and outer flange are of the same height; the annular groove on the right end face of the inner ring and the annular boss on the left end face of the inner ring of the connecting piece 4 correspond in position, shape, and size, and are fastened together; the annular groove on the right end face of the outer flange and the annular groove on the left end face of the outer ring of the connecting piece 4 are also located at the same height. The shapes and sizes correspond, and the through holes on the right end face of the outer flange correspond to the positions of the through holes on the outer ring of the connecting piece 4, which are used to coaxially install the right end face of the transition section 5, the connecting piece 4, and the axial air intake outer cylinder 3 through the fixing mechanism; the annular boss on the left side of the connecting piece 4 can be completely inserted into the annular groove of the inner ring of the transition section 5 and the outer flange; the right end of the hollow frustum section and the left end of the hollow cylindrical section have the same dimensions, and the two are formed as one piece, with the left end of the hollow frustum section being smaller than the right end; the international flange is fixedly connected to the left end of the hollow frustum section, and the center of the international flange is on the axis of the device; the outer wall of the hollow cylindrical section of the transition section 5 has a through hole, which is connected to the round hole in the middle of the inner ring on the right side of the transition section 5 through a welded bend, which is used to pass through the stainless steel pressure measuring tube 6; the part of the stainless steel pressure measuring tube 6 in the transition section 5 is placed in the bend.

[0012] The stainless steel pressure measuring tube 6 consists of multiple stainless steel tubes, with the right ends welded to the pressure measuring holes of the end cap 1. Each pressure measuring hole has one stainless steel tube welded to it. The tube passes sequentially to the left through the inner cylinder 2, the inner ring hole of the connecting piece 4, and the transition section 5. It bends at the hollow cylindrical section of the transition section 5 towards its outer wall hole, reaching the outer wall surface of the transition section 5 through the bend. After reaching the outer shell of the transition section 5, the stainless steel pressure measuring tube 6 connects to the sensor for pressure measurement.

[0013] 2) Inner cylinder end face pressure testing device under radial air intake conditions;

[0014] At this point, the adapter section 5 is removed, and the connecting piece 4 is replaced with the blind plate 7; the radial air intake outer cylinder 8 is used to replace the axial air intake outer cylinder 3. The radial air intake outer cylinder 8 has the same overall configuration as the axial air intake outer cylinder 3. The only difference is that the radial air intake outer cylinder 8 has multiple air intake holes along the circumferential direction near the left end flange. The air intake holes are circular and used for radial air intake; the blind plate 7 is a non-perforated annular plate structure, and the central circular hole is used for the stainless steel pressure measuring tube 6 to pass through; therefore, the left side of the blind plate 7 is a perforated plate, and the annular groove and through hole arranged on the right side are exactly the same as those arranged on the right side of the connecting piece 4. The connection and sealing method between the blind plate 7 and the inner cylinder 2 and the radial air intake outer cylinder 8 is the same as that of the inner cylinder end face pressure testing device under axial air intake conditions.

[0015] The working process of the rotating detonation combustion chamber inner cylinder end face pressure testing device is as follows:

[0016] Under the condition of axial intake, when the detonation engine works, the outlet generates a high-speed jet, so that a negative pressure area is generated near the end face of the inner cylinder; the static pressure measuring point on the upper surface of the end cover 1 can obtain the change of the pressure and transmit it through the plurality of stainless steel pressure gauges 6; the stainless steel pressure gauges 6 extend from the end cover 1 to the upstream direction in turn through the inner cylinder 2, the connecting piece 4 and the adapter section 5, and finally reach the outer shell of the adapter section 5; the stainless steel pressure gauges 6 are basically linear when they extend from the end cover 1 into the adapter section 5; since the outlet is located on the side wall of the adapter section 5, the stainless steel pressure gauges 6 are bent in the adapter section 5, so as to extend out of the outlet; the gas entering the adapter section 5 passes through the hollow part of the connecting piece 4 into the annular channel; the pressure is measured by the pressure sensor installed on the stainless steel pressure gauge 6 at the outlet; since the inner diameter of the stainless steel pressure gauge 6 is small, the viscous loss is large, which can reduce the pressure pulsation, so as to obtain a relatively stable static pressure value;

[0017] Under the condition of radial intake, when the detonation engine works, the outlet generates a high-speed jet, so that a negative pressure area is generated near the end face of the inner cylinder; the static pressure measuring point on the upper surface of the end cover 1 can obtain the change of the pressure and transmit it through the stainless steel tube; the stainless steel pressure gauges 6 extend to the upstream direction in turn through the inner cylinder 2 and the blind plate 7 and extend out of the blind plate 7, and the pressure is measured by the pressure sensor installed on the end part of the stainless steel tube on the left side of the blind plate 7; the gas enters the annular channel from the plurality of intake holes uniformly arranged on the circumferential surface of the radial intake outer cylinder 8; since the inner diameter of the stainless steel pressure gauge 6 is small, the viscous loss is large, which can reduce the pressure pulsation, so as to obtain a relatively stable static pressure value.

[0018] In a specific embodiment of the present application, the number of semi-head through holes of the end cover 1 is 4, and the four edges of the square formed by the radius of the disc where the pressure measuring hole is located and the center of the four semi-head through holes are parallel or perpendicular.

[0019] In another specific embodiment of the present application, the annular groove is used to place a copper gasket for sealing, so that there is a gap of about 1 mm between the annular boss and the annular groove, and the thickness of the copper gasket is slightly larger than the sum of the depths of the two annular grooves.

[0020] In still another specific embodiment of the present application, the inner diameter of the stainless steel pressure gauge 6 is less than 1 mm, and the outer diameter is set to 3 mm.

[0021] The device of the present application can obtain the end face static pressure value without affecting the tail flow field, so as to calculate the bottom resistance. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a perspective view of the inner cylinder end face pressure testing device under the condition of axial intake.

[0023] Figure 2 is the sectional view of the inner cylinder end face pressure testing device under axial air intake condition;

[0024] Figure 3 is the perspective view of the inner cylinder end face pressure testing device under radial air intake condition;

[0025] Figure 4 is the sectional view of the inner cylinder end face pressure testing device under radial air intake condition; Figure 5 is the schematic view of the connection between the end cover (1) and the inner cylinder (2) and the left end face of the inner cylinder (2) and the outer cylinder (3);

[0026] Figure 6 is the perspective view and sectional view of the connecting piece (4); Figure 7 is the perspective view of the adapter section (5);

[0027] Figure 8 is the perspective view of the blind plate (7). DETAILED DESCRIPTION

[0028] The application will be further described in detail below in combination with the drawings.

[0029] The application provides an inner cylinder end face pressure testing device for a rotary detonation combustion chamber under axial air intake and radial air intake conditions, which comprises an end cover 1, an inner cylinder 2, an axial air intake outer cylinder 3, a connecting piece 4, an adapter section 5, a pressure measuring pipe 6, a blind plate 7 and a radial air intake outer cylinder 8. The end cover 1, the inner cylinder 2 and the stainless steel pressure measuring pipe 6 are common structures, the axial air intake outer cylinder 3, the connecting piece 4 and the adapter section 5 are structures used under axial air intake condition, and the blind plate 7 and the radial air intake outer cylinder 8 are structures used under radial air intake condition.

[0030] Figure 1 which is the perspective view of the inner cylinder end face pressure testing device under axial air intake condition, Figure 2This is its cross-sectional view. Under axial intake conditions, when the detonation engine is operating, a high-speed jet is generated at the outlet, creating a negative pressure zone near the end face of the inner cylinder. The static pressure measuring point on the end cap 1 can obtain the pressure changes and transmit them through multiple stainless steel pressure measuring tubes 6. The stainless steel pressure measuring tubes 6 start from the end cap 1 and pass upstream sequentially through the inner cylinder 2, connecting piece 4, and transition section 5, finally reaching the outer shell of the transition section 5. The stainless steel pressure measuring tubes 6 are basically straight when extending from the end cap 1 into the transition section 5. Since the outlet is located on the side wall of the transition section 5, the stainless steel pressure measuring tubes 6 bend within the transition section 5, thus extending out from the outlet. As shown in the figure, the intake direction is indicated by the black arrow. The gas entering the transition section 5 enters the annular channel through the hollow part of the connecting piece 4. Pressure is measured by a pressure sensor installed on the stainless steel pressure measuring tube 6 at the outlet (the stainless steel tube has two ends: an inlet end and an outlet end; the inlet end is located on the end cap 1, and the outlet end extends from the side wall of the transition section 5). Because the stainless steel pressure testing tube 6 has a small inner diameter and a large viscosity loss, it can reduce pressure pulsation, thereby obtaining a more stable static pressure value. In a specific embodiment of the present invention, the stainless steel pressure testing tube 6 is directly welded to the end cap 1.

[0031] Figure 3 The image shown is a 3D view of the inner cylinder end face pressure testing device under radial air intake conditions. Figure 4 This is its cross-sectional view. Under radial intake conditions, when the detonation engine is operating, a high-speed jet is generated at the outlet, creating a negative pressure zone near the end face of the inner cylinder. The static pressure measuring point on the end cap 1 can obtain the pressure changes and transmit them through a stainless steel tube. The stainless steel pressure measuring tube 6 passes upstream through the inner cylinder 2 and the blind plate 7 and extends out from the blind plate 7, where a pressure sensor installed at the end of the stainless steel tube on the left side of the blind plate 7 measures the pressure. The intake direction is shown by the black arrow; gas enters the annular channel from multiple (e.g., four) evenly distributed intake holes around the radial intake outer cylinder 8. Due to the small inner diameter of the stainless steel pressure measuring tube 6, the viscosity loss is large, which can reduce pressure pulsation and thus obtain a more stable static pressure value. (The stainless steel pressure measuring tube has good toughness and can be bent. Under axial air intake conditions, a transition section 5 is required, therefore the pressure measuring tube cannot extend axially, otherwise measurement is impossible; it can only be bent and exit from the outer wall of the transition section 5. Under radial air intake conditions, the airflow can enter from the outer wall of the radial air intake outer cylinder 8, without needing to enter axially, therefore a blind flange 7 is required for sealing, otherwise air leakage will occur. In this case, the pressure measuring tube can extend axially from the blind flange 7 without interfering with the air intake section.)

[0032] In one embodiment of the present invention, such as Figure 1As shown, the end cover 1 is a disc structure with a certain thickness, near the outer circumference, along the circumferential direction, uniformly arranged with a plurality of (for example, four) semi-head through holes, along one radius direction of the disc, arranged with a plurality of pressure measuring holes. The positional relationship between the pressure measuring holes and the semi-head through holes is fixed, for example Figure 1 As shown in the middle, in one embodiment of the present application, the disc radius where the pressure measuring hole is located is parallel or perpendicular to the four sides of the square formed by the centers of the four semi-head through holes.

[0033] As shown Figure 5 The inner cylinder 2 is a hollow cylinder as a whole, and a throat is arranged at the left position in the middle and extends radially outward. The cross-sectional shape of the throat is an isosceles trapezoid without a bottom side, and the upper bottom of the trapezoid is smaller than the lower bottom. The lower bottom is on the outer surface of the hollow cylinder of the inner cylinder 2. The inner cylinder 2 is coaxially connected with the end cover 1, and a plurality of (for example, four) bosses are arranged on the inner wall surface at the position close to the right outlet of the inner cylinder 2. Threaded holes are arranged on the bosses, and the positions of the threaded holes are the same as those of the plurality of (for example, four) semi-head through holes on the end cover. Semi-head screws are used to connect the inner cylinder 2 and the end cover 1 from right to left, so as to ensure that the right plane of the end cover coincides with the right end surface of the inner cylinder 2. An inner flange is arranged on the left end surface of the inner cylinder 2, and an annular groove is opened on the inner flange. A plurality of through holes are arranged on the inner flange and are parallel to the axis of the device of the present application.

[0034] The axial air inlet outer cylinder 3 is a hollow cylinder as a whole, and an outer flange is arranged on the left end surface. An annular groove is opened on the outer flange, and a plurality of through holes are arranged on the outer flange and are parallel to the axis of the device of the present application. The inner cylinder 2 and the axial air inlet outer cylinder 3 are coaxial, and the end surfaces on both sides are flush.

[0035] As shown Figure 6 The connecting piece 4 is arranged in front of the inner cylinder 2 and the axial air inlet outer cylinder 3, and is a hollow annular structure as a whole. The connecting piece 4 includes concentric inner and outer rings, and the center of the connecting piece 4 is on the axis of the test device of the present application. The inner and outer rings are connected by a plurality of (for example, four) uniformly arranged rib plates. A plurality of through holes are arranged on the inner and outer rings, and the number of through holes on the inner ring is the same as that on the outer ring. An annular groove is arranged on the right side of the inner ring and the right side of the outer ring, respectively, and the annular grooves on the inner ring and the outer ring are concentric. The annular groove and the through hole on the right side of the inner ring correspond to the annular groove and the through hole arranged on the left end surface of the inner cylinder 2 in position, shape and size. The annular groove and the through hole on the right side of the outer ring correspond to the annular groove and the through hole arranged on the left end surface of the axial air inlet outer cylinder 3 in position, shape and size. For example, the inner ring is coaxially connected with the inner cylinder 2 by bolts, and the right side of the inner ring is sealed by a red copper gasket in the annular groove (the annular groove is used to place the red copper gasket for sealing. In order to ensure the sealing effect, the thickness of the red copper gasket is slightly larger than the sum of the depths of the annular grooves on both sides). The left end surfaces of the inner and outer rings are respectively provided with two concentric annular bosses.

[0036] As shown Figure 7As shown, the adapter section 5 is a hollow cylinder as a whole, including, from right to left, an outer flange with an inner ring, a hollow cylindrical section, a hollow circular truncated cone section, and an international flange. In the outer flange with the inner ring, the inner ring is connected to the outer flange by a plurality of (for example, 4) evenly distributed rib plates, which are exactly the same in shape and size as the rib plates in the connecting piece 4. The outer flange right end surface is arranged with an annular groove and a plurality of through holes parallel to the axial direction of the device of the application. The inner ring is a hollow cylinder with a bottom, and the bottom is annular. The center of the annular bottom is a through hole. The height of the inner ring, the rib plate, and the outer flange is consistent (the function of the adapter section 5 is mainly to connect the outer flange with the structure downstream, and the shape of the inner ring is convenient for placing the copper gasket for sealing). The inner ring right end surface annular groove and the annular ring-shaped boss set on the left end surface of the inner ring of the connecting piece 4 are corresponding in position, shape, and size, and are connected by buckling between them. The outer flange right end surface annular groove and the annular groove set on the left end surface of the outer ring of the connecting piece 4 are corresponding in position, shape, and size. The through holes on the outer flange right end surface are corresponding to the through holes on the outer ring of the connecting piece 4, which are used to coaxially install the right end surface of the adapter section 5, the connecting piece 4, and the axial inlet outer cylinder 3 by, for example, bolts. The annular boss on the left side of the connecting piece 4 can be completely placed in the annular groove of the inner ring and the outer flange of the adapter section 5. In practice, there is usually a gap of about 1mm between the annular boss and the annular groove, which is sealed by a copper gasket. The right end of the hollow circular truncated cone section and the left end of the hollow cylindrical section are exactly the same in size, and they are integrated. The left end of the hollow circular truncated cone section is smaller in size than the right end. The international flange is fixedly connected to the left end of the hollow circular truncated cone section (for example, by welding), and the center of the international flange is on the axis of the test device of the application. The outer wall surface of the hollow cylindrical section of the adapter section 5 is provided with a through hole, which is communicated with the circular hole in the middle of the inner ring on the right side of the adapter section 5 by a welded elbow pipe. The elbow pipe is used to pass through the stainless steel pressure measuring pipe 6 (which is flexible and can be bent), and the part of the stainless steel pressure measuring pipe 6 in the adapter section 5 is placed in the elbow pipe. The reason for using a welded elbow pipe is to ensure that the pressure measuring pipe reaches the outer wall surface of the adapter section 5 under the premise of sealing, which is convenient for pressure measurement.

[0037] The stainless steel pressure measuring pipe 6 is a plurality of stainless steel pipes, each welded at the pressure measuring hole position of the end cover 1. Each pressure measuring hole is welded with a stainless steel pipe, which passes through the inner cylinder 2, the inner ring hole of the connecting piece 4, and the adapter section 5 in turn, and is bent to the outer wall surface hole of the hollow cylindrical section of the adapter section 5, and reaches the outer wall surface of the adapter section 5 through the elbow pipe. In order to weaken the pressure pulsation and obtain a relatively stable static pressure value, the inner diameter of the stainless steel pressure measuring pipe 6 is small, for example, less than 1mm. In order to ensure the stiffness of the stainless steel pipe, the outer diameter is set to be about 3mm, for example. The stainless steel pressure measuring pipe 6 reaches the outer shell of the adapter section 5 and is connected to the sensor for pressure measurement.

[0038] The above scheme is an inner cylinder end surface pressure test device under the condition of axial inlet.

[0039] As Figure 3 andFigure 4 As shown, when radial inlet is adopted, the adapter section 5 is removed and the connecting plate 4 is replaced by a blind plate 7. The axial inlet outer cylinder 3 is replaced by a radial inlet outer cylinder 8, the only difference between the two is that the radial inlet outer cylinder 8 has a plurality of (for example, 4) inlet holes in the circumferential direction near the left end flange, the inlet holes are circular for radial inlet. The blind plate 7 is a non-hollow annular plate structure, and the circular hole in the middle is used for the stainless steel pressure pipe 6 to pass through. Therefore, the left side of the blind plate 7 is a perforated flat plate, and the annular groove and through hole arranged on the right side are exactly the same as those arranged on the right side of the connecting plate 4, and the connection and sealing mode of the blind plate 7 with the inner cylinder 2 and the radial inlet outer cylinder 8 are the same as described above.

Claims

1. A rotating detonation combustion chamber cylinder end face pressure testing device, characterized in that, It includes an end cap (1), an inner cylinder (2), an axial intake outer cylinder (3), a connecting piece (4), a transition section (5), a pressure measuring tube (6), a blind flange (7), and a radial intake outer cylinder (8); the end cap (1), the inner cylinder (2), and the stainless steel pressure measuring tube (6) are common structures, the axial intake outer cylinder (3), the connecting piece (4), and the transition section (5) are structures used under axial intake conditions, and the blind flange (7) and the radial intake outer cylinder (8) are structures used under radial intake conditions; among which 1) Test device for inner cylinder end face pressure under axial air intake conditions; The end cap (1) is a disc structure with a certain thickness. Near the outer circumference, there are multiple countersunk through holes evenly arranged along the circumference. Several pressure measuring holes are arranged along one radius of the disc. The positional relationship between the pressure measuring holes and the countersunk through holes is fixed. The inner cylinder (2) is a hollow cylinder with a throat located on the left side of the middle. The throat has an isosceles trapezoidal cross-section without a bottom edge, with the upper base smaller than the lower base. The lower base is on the outer surface of the hollow cylinder of the inner cylinder (2). The inner cylinder (2) is coaxially connected to the end cap (1). Multiple bosses are arranged on the inner wall near the right outlet. Threaded holes are arranged on the bosses, which are in the same position as the multiple countersunk holes on the end cap. The countersunk screws connect the inner cylinder (2) of the combustion chamber and the end cap (1) from right to left, ensuring that the right side plane of the end cap coincides with the right end face of the inner cylinder (2). An inner flange is arranged on the left end face of the inner cylinder (2), with an annular groove and multiple through holes parallel to the axial direction of the device. The center of the annular groove is on the axis of the device. The through holes are inside the annular groove. The axial intake outer cylinder (3) is a hollow cylinder with an outer flange on the left end face, an annular groove on it, and multiple through holes parallel to the axial direction of the device; the inner cylinder (2) and the axial intake outer cylinder (3) are coaxial and their two end faces are flush. The connecting piece (4) is arranged in front of the inner cylinder (2) and the axial air intake outer cylinder (3). The whole is a ring structure with a hollow center, including a concentric inner ring and an outer ring. The center of the ring is on the axis of the device. The inner and outer rings are connected by multiple evenly arranged ribs. Multiple through holes are arranged on both the inner and outer rings. The number of through holes is the same for both. An annular groove is arranged on the right side of the inner and outer rings respectively. The two are concentric. The annular groove and through hole on the right side of the inner ring correspond to the position, shape and size of the annular groove and through hole on the left end face of the inner cylinder (2). The annular groove and through hole on the right side of the outer ring correspond to the position, shape and size of the annular groove and through hole on the left end face of the axial air intake outer cylinder (3). The inner ring is coaxially connected to the inner cylinder (2) by a fixing mechanism. A concentric annular boss is also arranged on the left end face of the inner and outer rings respectively. The center of the annular boss is on the axis of the device. The transition section (5) is a hollow cylinder, and from right to left, it includes: an outer flange with an inner ring, a hollow cylindrical section, a hollow frustum section, and an international flange; in the outer flange with an inner ring, the inner ring and the outer flange are connected by multiple evenly distributed ribs, and the shape and size of the ribs are exactly the same as the ribs in the connecting piece (4); an annular groove is arranged on the right end face of the outer flange, and multiple through holes are set parallel to the axial direction of the device. The inner ring is a hollow cylinder with a bottom, and the bottom is annular. There is a through hole at the center of the bottom of the annular ring. The inner ring, ribs, and outer flange are of the same height; the annular groove on the right end face of the inner ring and the annular boss on the left end face of the inner ring of the connecting piece (4) correspond in position, shape, and size, and are fastened together; the annular groove on the right end face of the outer flange and the annular groove on the left end face of the outer ring of the connecting piece (4) correspond in position, shape, and size. The through hole on the right end face of the outer flange corresponds to the position of the through hole on the outer ring of the connecting piece (4), and is used to coaxially install the right end face of the transition section (5), the connecting piece (4), and the axial air intake outer cylinder (3) through the fixing mechanism; wherein the annular boss on the left side of the connecting piece (4) can be completely inserted into the annular groove of the inner ring of the transition section (5) and the outer flange; the right end of the hollow frustum section and the left end of the hollow cylindrical section are completely the same size, and the two are integrated into one piece, and the left end of the hollow frustum section is smaller than the right end; the international flange is fixedly connected to the left end of the hollow frustum section, and the center of the international flange is on the axis of the device; the outer wall of the hollow cylindrical section of the transition section (5) has a through hole, which is connected to the round hole in the middle of the inner ring on the right side of the transition section (5) through a welded bend, which is used to pass through the stainless steel pressure measuring tube (6); the part of the stainless steel pressure measuring tube (6) in the transition section (5) is placed in the bend; The stainless steel pressure measuring tube (6) consists of multiple stainless steel tubes, with the right end welded to the pressure measuring hole position of the end cap (1). Each pressure measuring hole is welded with a stainless steel tube, which passes through the inner cylinder (2), the inner ring hole of the connecting piece (4), and the transition section (5) in sequence to the left. The tube bends at the hollow cylindrical section of the transition section (5) towards its outer wall hole, and reaches the outer wall surface of the transition section (5) through the bend. After the stainless steel pressure measuring tube (6) reaches the outer shell of the transition section (5), it is connected to the sensor for pressure measurement. 2) Inner cylinder end face pressure testing device under radial air intake conditions; At this time, the adapter section (5) is removed and the connecting piece (4) is replaced with a blind plate (7); the radial air intake outer cylinder (8) is used to replace the axial air intake outer cylinder (3). The radial air intake outer cylinder (8) and the axial air intake outer cylinder (3) have the same overall configuration. The only difference is that the radial air intake outer cylinder (8) has multiple air intake holes along the circumferential direction near the left end flange. The air intake holes are circular and used for radial air intake. The blind plate (7) is a non-perforated annular plate structure. The central circular hole is used for the stainless steel pressure measuring tube (6) to pass through. Therefore, the left side of the blind plate (7) is a perforated plate, and the annular groove and through hole arranged on the right side are exactly the same as those arranged on the right side of the connecting piece (4). The connection and sealing method between the blind plate (7) and the inner cylinder (2) and the radial air intake outer cylinder (8) is the same as that of the inner cylinder end face pressure testing device under axial air intake conditions.

2. The rotating detonation combustion chamber cylinder end face pressure testing device as described in claim 1, characterized in that, Its working process is as follows: Under axial intake conditions, when the detonation engine is working, a high-speed jet will be generated at the outlet, resulting in a negative pressure zone near the end face of the inner cylinder. The static pressure measuring point on the end cap (1) can obtain the pressure change and transmit it through multiple stainless steel pressure measuring tubes (6). The stainless steel pressure measuring tube (6) starts from the end cap (1), passes through the inner cylinder (2), connecting piece (4) and transition section (5) in sequence upstream, and finally reaches the outer shell of the transition section (5). The stainless steel pressure measuring tube (6) is basically straight when it extends from the end cap (1) into the transition section (5). Since the outlet is located on the side wall of the transition section (5), the stainless steel pressure measuring tube (6) bends in the transition section (5) so that it can extend out from the outlet. The gas entering the transition section (5) enters the annular channel through the hollow part of the connecting piece (4). The pressure is measured by the pressure sensor installed on the stainless steel pressure measuring tube (6) at the outlet. Since the inner diameter of the stainless steel pressure measuring tube (6) is small and the viscosity loss is large, it can reduce pressure pulsation and obtain a more stable static pressure value. Under radial intake conditions, when the detonation engine is working, a high-speed jet will be generated at the outlet, resulting in a negative pressure zone near the end face of the inner cylinder. The static pressure measuring point on the end cap (1) can obtain the pressure change and transmit it through the stainless steel pipe. The stainless steel pressure measuring tube (6) passes through the inner cylinder (2) and the blind plate (7) in the upstream direction and extends out from the blind plate (7). The pressure is measured by the pressure sensor installed at the end of the stainless steel pipe on the left side of the blind plate (7). The gas enters the annular channel from multiple air inlets evenly distributed around the radial intake outer cylinder (8). Since the inner diameter of the stainless steel pressure measuring tube (6) is small and the viscosity loss is large, it can reduce pressure pulsation and thus obtain a more stable static pressure value.

3. The rotating detonation combustion chamber cylinder end face pressure testing device as described in claim 1, characterized in that, The end cap (1) has four countersunk holes. The radius of the disk where the pressure test hole is located is parallel or perpendicular to the four sides of the square formed by the centers of the four countersunk holes.

4. The rotating detonation combustion chamber cylinder end face pressure testing device as described in claim 1, characterized in that, The annular groove is used to place a copper gasket for sealing, so that there is a gap of about 1mm between the annular boss and the annular groove. The thickness of the copper gasket is slightly greater than the sum of the depths of the two annular grooves.

5. The rotating detonation combustion chamber cylinder end face pressure testing device as described in claim 1, characterized in that, The stainless steel pressure testing tube (6) has an inner diameter of less than 1 mm and an outer diameter of 3 mm.

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