A skew ramp skid device based on oblique detonation engine experiment

Abstract

The present application belongs to the technical field of oblique detonation engine experiment, and particularly relates to an oblique wedge sliding rail device based on oblique detonation engine experiment, which solves the problem that the existing oblique detonation engine cannot meet the requirements of changing the starting point of the oblique wedge independently and changing the process simply and at low cost. The device is characterized in that: the left and right end faces of the combustion chamber are open; the nozzle is arranged on the right side of the combustion chamber and the inner cavities of the two are connected; the two nozzle side wall surfaces on the front and back sides of the nozzle are fixedly connected with the lower nozzle wall surface or the three are an integral part, and the left ends of the three are respectively and one-to-one correspondingly fixedly connected with the front and back wall surfaces of the combustion chamber and the right end of the lower wall surface of the combustion chamber; the lower nozzle wall surface is arranged in a left-high-right-low inclined manner; the upper nozzle wall surface is arranged between the two nozzle side wall surfaces and arranged in a left-low-right-high inclined manner; the oblique wedge is arranged in the inner cavity of the combustion chamber and is detachably fixed to the left end of the upper nozzle wall surface; the sliding rail is fixedly arranged on the outer upper surface of the upper wall surface of the combustion chamber; and the sliding block is fixedly connected to the outer upper surface of the upper wall surface of the nozzle and slides left and right along the sliding rail.

Description

Technical Field

[0001] This invention belongs to the field of experimental technology of oblique detonation engine, and specifically relates to an oblique cleaving slide rail device based on oblique detonation engine experiments. Background Technology

[0002] In recent years, power technology in the high Mach number field has continued to develop and has made great breakthroughs. However, many problems have also been encountered in the process of exploration. Researchers intend to find a combustion organization mode that is more suitable for high Mach numbers.

[0003] The detonation wave is a shock wave with chemical reaction that propagates at supersonic speed. The thermodynamic state parameters behind the wave increase sharply, and the reactants cross the detonation wave surface and quickly transform into combustion products and release energy. Detonation combustion is approximately isochoric combustion and has a higher thermodynamic cycle efficiency than deflagration combustion [1]. Oblique detonation is a combustion achieved by generating an induced oblique shock wave (OSW) on a wedge-shaped configuration by a high-speed incoming flow and coupling it with the combustion wave. The oblique detonation engine is a device based on oblique detonation combustion.

[0004] The oblique detonation induced by the wedge is one of the typical initiation methods commonly used in oblique detonation experiments. The initiation and propagation of the detonation wave in the confined space are affected by the complex wave system reflected by the upper wall, which is very different from that in the infinite space. Lee et al. [2] numerically simulated the detonation process in the confined space and found that wall reflection can also induce detonation initiation and reduce the Mach number requirement of the incoming flow. The expansion wave and separation bubble caused by the geometric expansion at the end of the confined space will affect the stationary shape and stability of the detonation wave surface. Li Guanxiao et al. [3] numerically simulated the effect of the position of the starting point of the expansion section of the combustion chamber relative to the wedge surface of the detonation wave on the stationary position of the detonation initiation and found that the expansion wave at the starting point of the expansion section can interact with the detonation wave to form a local separation zone. The wedge angle is also one of the important factors affecting the stationary position of the detonation. Liu Yu et al. [4] found through wind tunnel experiments that the detonation cannot be initiated if the wedge angle is too small. Han Xin et al. [5] found through theoretical analysis and numerical simulation that if the wedge angle is too large, it is easy to form an overdriven oblique detonation shock wave, which will also generate additional resistance. Jiang Zonglin [6] proposed that detonation can only be initiated when the incoming flow and the wedge surface are greater than a certain value. Peng Jun et al. [7] obtained the range of wedge angles that can work normally under a specified incoming flow Mach number through numerical simulation. Therefore, designing an experimental device with variable wedge starting point and wedge angle is of great research significance.

[0005] Regarding patents, Chen Weiqiang et al. [8] disclosed a detonation engine and propulsion system, whose wedge angle is a telescopic mechanical structure that can be adjusted according to the incoming flow. Tang Hao et al. [9] disclosed a detonation engine with a double support rod assembly controlling the wedge angle and other shapes to optimize the detonation wave. Zhang Xiaobing et al.

[10] invented a new type of wedge structure with a local large-angle wedge, the two ends of which are rotatably connected to the front wedge and the rear wedge respectively to control the detonation wave initiation position. Teng Honghui et al.

[11] disclosed a device to further stabilize the detonation by controlling the position of the front and rear sections of the combustion chamber wall through incoming flow monitoring and action controller. Teng Honghui et al.

[12] also disclosed a device to control the shape of the upper wall of the combustion chamber, which controls the two nodes of the shape through two telescopic rods to control the detonation wave. The devices invented by the researchers above do not involve single-variable testers for the wedge starting point or wedge angle. Their focus is on engineering design. Changing the telescopic rod will change the wedge angle, height and wedge starting point, etc., with many coupled variables and complex mechanical structure, which is not conducive to experimental research on single-variable stable control of the wedge starting point position. Chen Shuo et al.

[13] disclosed an experimental device for a detonation combustion chamber. The lower wall of the combustion chamber is a detachable structure. After the lower wall is detached, the wedge angle and starting point position can be changed. Although it can change the wedge starting point or wedge angle separately, the detachable structure is not conducive to experimental operation. The lower wall of the combustion chamber needs to be replaced each time, which also consumes a lot of materials and has high cost.

[0006] The following is a description of the cited documents used in the background section above:

[0007] [1] Miao Shikun, Zhou Jin, Liu Yu, et al. A review of the research progress on oblique detonation in supersonic airflow [J]. Experimental Fluid Mechanics, 2019, 33(01):41-53.

[0008] [2]LeeH,FanW,XiaoQ.Numerical investigation of the initiation and propagation of obliquedetonation wavesinaconfinedcombustionchamber[C].The52ndAIAA / SAE / ASEEJointPropulsionConference,2016.

[0009] [3] Li Guanxiao, Teng Honghui, Zhang Guoqing. Study on the stability of two-dimensional oblique detonation waves based on the influence of confined space [C]. Chinese Congress of Theoretical and Applied Mechanics, 2019.

[0010] [4] Liu Yu, Zhou Jin, Lin Zhiyong. Slope-induced oblique detonation waves under the effect of incoming boundary layer [J]. Acta Physica Sinica, 2014, 63(20):225-232.

[0011] [5] Han Xin, Liu Yunfeng, Zhang Zijian, et al. Theoretical methods to improve the thrust of high Mach number scramjet engines [J]. Acta Mechanica Sinica, 2022, 54(03):633-643.

[0012] [6] Jiang Zonglin. On supersonic combustion and hypersonic power [J]. Progress in Mechanics, 2021, 51(01):130-140.

[0013] [7] Peng Jun, Ma Jiawen, Yang Pengfei, et al. Numerical study on the evolution of oblique detonation wave system in confined space and its critical conditions [J]. Propulsion Technology, 2021, 42(04):738-744.

[0014] [8] Chen Weiqiang, Liang Jianhan, Cai Xiaodong, Lin Zhiyong, Liu Shijie, Yuan Xueqiang, Jiang Luxin, Sun Jian. A supersonic detonation engine and its propulsion system [P]. Hunan, China: CN106968833A, 2017-07-21.

[0015] [9] Tang Hao, Chen Nan, Xu Pengfei. A stationary detonation engine based on variable wedge angle [P]. Jiangsu Province, China: CN108488004A, 2018-09-04.

[0016]

[10] Zhang Xiaobing, Qin Qiongyao. A wedge structure for controlling oblique detonation waves using local large-angle wedges [P]. Jiangsu Province, China: CN111608820A, 2020-09-01.

[0017]

[11] Teng Honghui, Xi Xuechen, Wang Kuanliang, Zhang Yuhang. A method for stationary control of oblique detonation shock waves and a variable geometry combustion chamber [P]. Beijing, China: CN112594737A, 2021-04-02.

[0018]

[12] Teng Honghui, Wang Kuanliang. An integrated control method and device for combustion chamber nozzle of a detonation engine [P]. Beijing, China: CN112761817A, 2021-05-07.

[0019]

[13] Chen Shuo, Ma Hu, Xia Zhenjuan, Xie Zongqi, Li Sheng. An experimental device for the combustion chamber of a detonation engine with variable wedge angle and starting point [P]. Jiangsu Province, China: CN115307919A, 2022-11-08.

[0020]

[14] Zhang Xiaobing, Qin Qiongyao. A wedge structure for controlling oblique detonation waves using local large-angle wedges [P]. Jiangsu Province, China: CN111608820A, 2020-09-01. Summary of the Invention

[0021] The purpose of this invention is to provide a sloping slide rail device based on sloping detonation engine experiments, so as to solve the technical problem that existing sloping detonation engines cannot both satisfy the requirement that the sloping starting point can be changed independently and that the change process is simple and low-cost.

[0022] The technical solution adopted in this invention is a slanted slide rail device based on slanted detonation engine experiments, which is special in that:

[0023] Includes combustion chamber, nozzle, wedge, and slide rail slider assembly;

[0024] The combustion chamber has a cuboid shape with open left and right end faces; symmetrical observation windows are provided on the front and rear walls of the combustion chamber; the left end of the combustion chamber is used to connect to the mixing section.

[0025] The nozzle is located on the right side of the combustion chamber and the inner cavities of the two are connected; the two nozzle sidewalls on the front and rear sides of the nozzle are fixedly connected to the lower wall of the nozzle or the three are a single piece, and the left ends of the three are respectively fixedly connected to the front and rear walls of the combustion chamber and the right end of the lower wall of the combustion chamber; the lower wall of the nozzle is inclined with the left side higher than the right side, and the intersection of the inner surface of the left end and the right end of the lower wall of the combustion chamber is the starting position of the expansion section of the lower wall of the nozzle; the upper wall of the nozzle is located between the two nozzle sidewalls and is inclined with the left side lower than the right side.

[0026] The wedge is installed in the inner cavity of the combustion chamber and the nozzle, and is detachably fixed to the left end of the upper wall of the nozzle; the upper horizontal plane of the wedge is tangent to the inner surface of the upper wall of the combustion chamber, and the inclined surface of the wedge intersects the upper horizontal plane of the wedge at the left end of the wedge, which is the starting point of the wedge.

[0027] In the slide rail and slider assembly, the slide rail is fixedly mounted on the outer upper surface of the upper wall of the combustion chamber, and the slider is fixedly connected to the outer upper surface of the upper wall of the nozzle and can slide left and right along the slide rail.

[0028] Furthermore, in order to reduce assembly gaps and assembly surfaces, and to avoid unnecessary shock waves generated in the flow field during the experiment, which would affect the internal flow field, the inner surfaces of the two nozzle sidewalls are respectively coplanar with the corresponding inner surfaces of the front and rear walls of the combustion chamber.

[0029] Furthermore, in order to simplify the structure of the slide rail slider assembly and to position and lock the slider on the track when it slides to the appropriate position, the slide rail slider assembly also includes a slider fixing component;

[0030] The slide rail includes a transition section and a track arranged sequentially from left to right; the track is fixedly connected to the outer upper surface of the combustion chamber upper wall through the transition section; the track is a shape formed by stretching a track cross section perpendicular to the left and right direction along the axis of the left and right direction, and the shape of the track cross section is a first rectangle;

[0031] The slider is fixed to the outer upper surface of the nozzle wall via a slider connecting plate; the slider is formed by stretching a slider cross-section perpendicular to the left-right direction along the left-right axis; the shape of the slider cross-section is that the inside is a second rectangle, and the outside is a shape formed by a third rectangle above and a trapezoid or fourth rectangle below, with the bottom two vertices of the upper third rectangle coinciding with the top two vertices of the lower trapezoid or fourth rectangle; the size of the second rectangle inside the slider cross-section is adapted to the size of the track cross-section, and the slider is fitted onto the track;

[0032] The slider fixing assembly is used to position and lock the slider onto the track.

[0033] Furthermore, in order to simplify the operation of positioning and locking the slider on the track and to ensure reliable positioning and locking of the slider, the slider fixing assembly includes at least two flange bolts, an equal number of nuts that are adapted to the flange bolts, and a plurality of screws.

[0034] At least two track grooves are arranged in an array along the front-to-back direction on the lower surface of the track; the track grooves extend in the left-to-right direction, and the cross-sectional dimensions of the track grooves are adapted to the outer dimensions of the nut; multiple track positioning through holes are arranged in an array along the left-to-right direction on the bottom plane of each track groove, with the same starting position, hole spacing, and number of holes, and the diameter of the track positioning through holes is adapted to the radial dimension of the flange bolt.

[0035] A U-shaped groove with a U-shaped cross-section and the U-shaped opening facing right is provided on the upper surface of the slider at the right end position. The number of U-shaped grooves is equal to the number of track grooves, and their front-to-back position is adapted to the front-to-back position of the track grooves. The U-shaped dimension of the U-shaped groove is adapted to the radial dimension of the flange bolt.

[0036] The flange bolt passes through the U-shaped groove and the track positioning through hole in sequence, and is connected to the nut that is clamped in the track groove to limit the freedom of the slider to slide left and right on the track; the lower surface of the inner cavity of the slider is provided with a clearance groove equal in number to the U-shaped groove and whose position corresponds to the position of the U-shaped groove, the clearance groove is used to make way for the tail end of the bolt after the flange bolt extends out of the nut;

[0037] Multiple threaded holes adapted to the screws are provided on the upper surface and the front and rear sides of the slider. The number of screws is equal to the number of threaded holes. The screws are set in the threaded holes to restrict the slider's degrees of freedom in the up-down and back-forward directions.

[0038] Furthermore, when the axis of the leftmost track positioning through-hole in the array of multiple track positioning through-holes is in the same vertical plane as the rightmost vertical end face of the wedge and the starting position of the expansion section of the lower wall of the nozzle, the flange bolt is positioned near the leftmost end of the U-shaped groove, and the axis of the flange bolt is coaxial. This arrangement provides a measurement benchmark for measuring the displacement of the wedge starting point, facilitating the measurement of the displacement of the wedge starting point during experiments. Since the wedge starting point plays a dominant role in detonation relative to the starting position of the expansion section of the lower wall of the nozzle, this arrangement facilitates the study of the influence of the wedge starting point position on the detonation wave initiation and stationary phase.

[0039] Furthermore, the spacing between the multiple track positioning through holes is 10mm ± 0.2mm. This configuration ensures that, given the identical structure and dimensions of the connection between the wedges with different wedge angles and the upper wall of the nozzle—that is, when the height of the rightmost vertical surface of the wedge remains constant—the wedges in this invention can be replaced with those commonly used in daily experiments (wedge angles of 20°, 25°, and 30°). This allows the wedge starting point to remain unchanged, with only the wedge angle being changed, thus enabling the study of the effect of individually changing the wedge angle on the detonation wave initiation and stationary phase.

[0040] Furthermore, in order to achieve better positioning, locking, and guiding effects, as well as a simple structure and low cost, the number of track grooves provided on the lower surface of each track, the number of U-shaped grooves provided on the upper surface of each slider at the right end, and the number of clearance grooves provided on the lower surface of the inner cavity of the slider are all two.

[0041] The slider fixing assembly includes two flange bolts and two nuts;

[0042] There are two sets of slide rail slider assemblies; the two sets of slide rail slider assemblies are symmetrically arranged in the front and back direction along the combustion chamber.

[0043] Furthermore, to facilitate the replacement of the wedge, a wedge connecting plate is fixedly connected to the right end of the upper wall of the nozzle, and the plate surface of the wedge connecting plate is perpendicular to the left and right directions; on the left side of the wedge connecting plate, a nozzle upper wall positioning protrusion protruding to the left is provided at the front and rear sides for positioning and fitting when connected with the wedge.

[0044] The wedge is formed by stretching a right triangle perpendicular to the front-back direction along the front-back axis; a wedge positioning groove adapted to the positioning protrusion on the upper wall of the nozzle is provided on the vertical end face of the rightmost end of the wedge.

[0045] The wedge is detachably fixed to the left end of the upper wall of the nozzle via a wedge connecting plate.

[0046] Furthermore, for structural simplicity, only one observation window is provided on each of the front and rear walls of the combustion chamber, and the front and rear walls of the combustion chamber are served by the observation window frames.

[0047] Furthermore, for ease of connection, a combustion chamber flange is provided at the left end of the combustion chamber, which is connected to the mixing section.

[0048] The beneficial effects of this invention are:

[0049] (1) The oblique detonation engine experimental oblique detonation slide rail device of the present invention is a slide rail type oblique detonation combustion chamber. The oblique wedge moves left and right as the slider slides left and right on the slide rail, driven by the upper wall of the nozzle. Therefore, the position of the oblique wedge in the left and right direction can be adjusted independently, that is, the starting point of the oblique wedge can be changed independently. In the present invention, the slide rail slider assembly is used to change the starting point position of the oblique wedge. The slide rail and slider are non-disassembly structures, which makes the operation of changing the starting point position of the oblique wedge simple, saves manpower and material resources, and has low cost. Therefore, the present invention solves the technical problem that existing oblique detonation engines cannot satisfy both the requirement that the starting point of the oblique wedge can be changed independently and the requirement that the change process is simple and low cost. The oblique wedge in the present invention is detachably fixed to the left end of the upper wall of the nozzle, which allows the oblique wedge to be replaced and provides the conditions for adjusting the oblique wedge angle independently.

[0050] (2) The oblique detonation engine experiment based on the present invention has an oblique detonation slide rail device that can adjust the oblique detonation position in a small range and a wide range through the slide rail slider assembly, so that the detonation wave is stationed at an ideal position relative to the end of the confined space to obtain the best detonation wave shape and the best performance. At the same time, it can study the influence of the change of the relative position between the starting position of the expansion section of the nozzle lower wall and the starting point of the oblique detonation on the oblique detonation wave.

[0051] (3) In this invention, a plurality of track positioning through holes are preferably arranged in an array along the left and right direction on the track. The hole spacing between the plurality of track positioning through holes can be set very small, which can provide multiple positions for the wedge in the left and right direction, thereby providing more working conditions for the experiment and facilitating experimental research.

[0052] (4) In this invention, preferably, the axis of the leftmost track positioning through hole in the array of multiple track positioning through holes is in the same vertical plane as the vertical end face of the rightmost end of the wedge and the starting position of the expansion section of the lower wall of the nozzle. The flange bolt is set at the leftmost end of the U-shaped groove, and the axis of the flange bolt is coaxial. This setting provides a measurement benchmark for measuring the displacement of the wedge starting point, which is convenient for measuring the displacement of the wedge starting point during the experiment. Since the wedge starting point plays a dominant role in the detonation relative to the starting position of the expansion section of the lower wall of the nozzle, this setting facilitates the study of the influence of the wedge starting point position on the detonation wave initiation and stationary position.

[0053] (5) In this invention, the hole spacing of the multiple track positioning through holes is preferably 10mm ± 0.2mm. With this setting, when the structure and size of the part where the wedge with different wedge angles connects to the upper wall of the nozzle are exactly the same, that is, when the height of the vertical surface of the rightmost end of the wedge remains unchanged in the vertical direction, when the wedge in the device of this invention is replaced among the wedges with wedge angles of 20°, 25° and 30° commonly used in daily experiments, the starting point of the wedge can remain unchanged, and only the wedge angle can be changed. Thus, the influence of changing the wedge angle alone on the detonation wave initiation and stationary state can be studied. Attached Figure Description

[0054] Figure 1 This is a three-dimensional structural schematic diagram of an embodiment of the present invention;

[0055] Figure 2 This is a front view of an embodiment of the present invention;

[0056] Figure 3 yes Figure 2 The left view;

[0057] Figure 4 This is a partial schematic diagram of the observation window in an embodiment of the present invention;

[0058] Figure 5 This is a partial schematic diagram of the slider being assembled on the slide rail in an embodiment of the present invention;

[0059] Figure 6 This is a schematic diagram of the structure in an embodiment of the present invention that uses flange bolts to restrict the slider to slide left and right on the track;

[0060] Figure 7 This is a three-dimensional structural schematic diagram of the sliding part that can slide left and right relative to the combustion chamber in an embodiment of the present invention (the oblique wedge is not shown in the figure);

[0061] Figure 8 This is a schematic diagram of the diagonal wedge structure in an embodiment of the present invention.

[0062] The labels in the diagram are explained as follows:

[0063] 1. Combustion chamber, 1-1. Upper wall of combustion chamber, 1-2. Lower wall of combustion chamber, 2. Combustion chamber flange, 2-1. Upper flange, 2-2. Lower flange, 3. Observation window, 3-1. Observation window frame, 3-2. Observation window glass gasket, 3-3. Observation window glass, 3-4. Observation window pressure plate gasket, 3-5. Observation window pressure plate, 4. Slide rail, 4-1. Transition section, 4-2. Rail, 4-3. Rail groove, 4-4. Rail positioning through hole, 4-5. Nut, 4-6. Flange bolt, 5. Wedge, 5-1. Wedge positioning groove, 6. Upper wall of nozzle, 6-1. Wedge connecting plate, 6-2. Positioning protrusion of upper wall of nozzle, 7. Slider, 7-1. Slider connecting plate, 7-2. U-shaped groove, 7-3. Screw, 8. Side and lower wall of nozzle, 8-1. Side wall of nozzle, 8-2. Lower wall of nozzle. Detailed Implementation

[0064] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0065] See Figure 1 This invention discloses a slant slide rail device based on a slant detonation engine experiment, comprising a combustion chamber 1, a nozzle, a slant rail 5, and a slide rail slider assembly. The x-axis, y-axis, and z-axis in the accompanying drawings are defined as follows: the flow direction of the combustion chamber from left to right is the positive x-axis direction; the direction perpendicular to the x-axis and pointing directly above the flow channel of the combustion chamber is the positive y-axis direction; the positive z-axis direction conforms to the right-hand rule, i.e., the positive z-axis direction points forward.

[0066] See Figure 1 , Figure 2 and Figure 3The combustion chamber 1 has a rectangular parallelepiped shape with open left and right end faces. The combustion chamber 1 is designed to accommodate structures such as the oblique wedge 5, inducing oblique detonation combustion. Symmetrical observation windows 3 are provided on the front and rear walls of the combustion chamber 1. The left end of the combustion chamber 1 is connected to the mixing section. The nozzle is located on the right side of the combustion chamber 1, and the two cavities are connected. The two nozzle sidewalls 8-1 on the front and rear sides of the nozzle are fixedly connected to the lower nozzle wall 8-2, or all three are integral components. The left ends of these three components are respectively fixedly connected to the front and rear walls of the combustion chamber 1 and the right end of the lower nozzle wall 1-2. The lower nozzle wall 8-2 is inclined from left to right, and the intersection of its left end and the inner surface of the connection point between the left end and the right end of the lower nozzle wall 1-2 marks the beginning of the expansion section of the lower nozzle wall. Starting position; the upper wall 6 of the nozzle is positioned between the two side walls 8-1 of the nozzle, and is inclined with the left side lower than the right side; the combustion products expand and accelerate through the nozzle, fully converting their thermal energy into the kinetic energy of the combustion gas, thereby providing thrust to the engine; the wedge 5 is positioned in the inner cavity of the combustion chamber 1 and the nozzle, and is detachably fixed to the left end of the upper wall 6 of the nozzle; the upper horizontal plane of the wedge 5 is tangent to the inner surface of the upper wall 1-1 of the combustion chamber 1, and the inclined surface of the wedge 5 intersects the upper horizontal plane of the wedge 5 at the left end of the wedge 5, which is the starting point of the wedge; in the slide rail slider assembly, the slide rail 4 is fixedly positioned on the outer upper surface of the upper wall 1-1 of the combustion chamber, and the slider 7 is fixedly connected to the outer upper surface of the upper wall 6 of the nozzle, and can slide left and right along the slide rail 4; see Figure 1 and Figure 7 The slider 7, the upper wall of the nozzle 6, and the detachable wedge 5 together form the sliding part. When the slider 7 moves in the left and right direction, the wedge 5 moves relative to the upper wall of the combustion chamber 1-1 through the upper wall of the nozzle 6.

[0067] See Figure 1 In order to reduce assembly gaps and assembly surfaces, and to avoid unnecessary shock waves generated by the incoming flow in the flow field during the experiment, which would affect the internal flow field, this embodiment preferably has the inner surfaces of the two nozzle sidewalls 8-1 respectively coplanar with the corresponding inner surfaces of the front and rear walls of the combustion chamber 1.

[0068] See Figure 1 and Figure 2 In this embodiment, for structural simplicity, only one observation window 3 is provided on each of the front and rear walls of the combustion chamber 1, and the front and rear walls of the combustion chamber 1 are served by the observation window frame 3-1 of the observation window 3. The observation window 3 is used to capture the morphology and development process of the detonation wave during the experiment. See also Figure 4In this embodiment, the observation window 3 includes an observation window frame 3-1, an observation window glass 3-3, and an observation window pressure plate 3-5. The four edges of the observation window frame 3-1 and the four edges of the observation window glass 3-3 are stepped. The inner surfaces of the observation window frame 3-1 and the observation window glass 3-3 on the side of the combustion chamber 1 are flush with the corresponding inner surface of the combustion chamber 1. An observation window glass pad 3-2 is provided around the observation window glass 3-3 and the observation window frame 3-1. The observation window glass pad 3-2 is placed inside the observation window frame 3-1, with an outer diameter slightly smaller than the outer diameter of the observation window glass 3-3 and an inner diameter slightly larger than the inner diameter of the corresponding step of the observation window frame 3-1. It serves to seal between the observation window glass 3-3 and the observation window frame 3-1 and to average the stress when the observation window glass 3-3 is fixed, preventing cracking. The stepped observation window glass 3-3, embedded in the observation window frame 3-1, provides observation of the detonation wave while also isolating the outside air and providing a sealed environment. The aforementioned observation window pressure plate 3-5 is used to fix the observation window glass 3-3 in the observation window frame 3-1. The observation window pressure plate 3-5 is located on the side of the observation window glass 3-3 away from the combustion chamber 1 cavity, and observation window pressure plate pads 3-4 are provided around the perimeter between the observation window pressure plate 3-5 and the observation window glass 3-3. The outer diameter of the observation window pressure plate pads 3-4 is slightly smaller than the outer diameter of the observation window pressure plate 3-5, and its inner diameter is slightly larger than the inner diameter of the observation window pressure plate 3-5. These pads serve to seal between the observation window pressure plate 3-5 and the observation window glass 3-3, and also to average the stress during the fixing of the observation window glass 3-3, preventing cracking.

[0069] See Figure 1 , Figure 2 and Figure 3 For ease of connection, in this embodiment, a combustion chamber flange 2 is provided at the left end of the combustion chamber 1, which is connected to the mixing section. In this embodiment, the combustion chamber flange 2 is presented as an upper flange 2-1 and a lower flange 2-2, with five through holes evenly distributed in each row of flanges.

[0070] See Figure 1 For ease of processing, in this embodiment, the two nozzle sidewalls 8-1 located on the front and rear sides of the nozzle and the nozzle lower wall 8-2 are integral parts, i.e., nozzle side-lower wall 8. Figure 1 As can be seen, in this embodiment, the observation window frame 3-1 is connected to the upper wall 1-1 of the combustion chamber, the lower wall 1-2 of the combustion chamber, the combustion chamber flange 2, and the nozzle side-lower wall 8.

[0071] See Figure 1To simplify the slide rail slider assembly structure and ensure that the slider is positioned and locked onto the track when it slides to the appropriate position, the slide rail slider assembly also includes a slider fixing assembly; the slide rail 4 includes a transition section 4-1 and a track 4-2 arranged sequentially from left to right; the track 4-2 is fixedly connected to the outer upper surface of the combustion chamber upper wall 1-1 via the transition section 4-1; from Figure 1 and Figure 3 As can be seen, in this embodiment, the transition section 4-1 also connects the upper wall 1-1 of the combustion chamber to the upper flange 2-1. The track 4-2 is formed by stretching a track cross-section perpendicular to the left-right direction along the axis of the left-right direction, and the shape of the track cross-section is a first rectangle. In this embodiment, the track 4-2 extends outward from the outer upper surface of the upper wall 1-1 of the combustion chamber to one right end of the upper wall 1-1. The slider 7 is fixed to the outer upper surface of the upper wall 6 of the nozzle via a slider connecting plate 7-1. The slider 7 is formed by stretching a slider cross-section perpendicular to the left-right direction along the axis of the left-right direction. The shape of the slider cross-section is that the inner part is a second rectangle, and the outer part is formed by a third rectangle above and a trapezoid or fourth rectangle below, with the lower two vertices of the upper third rectangle coinciding with the upper two vertices of the lower trapezoid or fourth rectangle. The size of the inner second rectangle of the slider cross-section is adapted to the size of the track cross-section, and the slider 7 is fitted onto the track 4-2. The slider fixing assembly is used to position and lock the slider 7 onto the track 4-2. See also... Figure 1 , Figure 5 as well as Figure 6To simplify the operation of positioning and locking the slider on the track, and to ensure reliable positioning and locking of the slider, the slider fixing assembly in this embodiment includes at least two flange bolts 4-6, an equal number of nuts 4-5 adapted to the flange bolts 4-6, and multiple screws 7-3. At least two track grooves 4-3 are arranged in an array along the front-back direction on the lower surface of the track 4-2; the track grooves 4-3 extend in the left-right direction, and their cross-sectional dimensions are adapted to the external dimensions of the nuts 4-5, serving to hold the nuts 4-5. When the nuts 4-5 are placed in the track grooves 4-3, they can be rotated and locked. Multiple track grooves, with the same starting position, hole spacing, and number of holes in the left-right direction, are arranged in an array along the left-right direction on the bottom plane of each track groove 4-3. The track positioning through hole 4-4 has a diameter that matches the radial dimension of the flange bolt 4-6. A U-shaped groove 7-2, with a U-shaped cross-section and the U-shaped opening facing right, is provided on the upper surface of the slider 7 at its right end. The number of U-shaped grooves 7-2 is equal to the number of track grooves 4-3, and their front-to-back position matches that of the track grooves 4-3. The U-shaped dimension of the U-shaped groove 7-2 matches the radial dimension of the flange bolt 4-6. (See also...) Figure 6 The flange bolts 4-6 pass sequentially through the U-shaped groove 7-2 and the track positioning through hole 4-4, and then connect with the nut 4-5, which is fitted in the track groove 4-3, to restrict the left and right sliding freedom of the slider 7 on the track 4-2. After the flange bolts 4-6 are tightened, the lower surface of the flange of the flange bolts 4-6 coincides with the upper surface of the U-shaped groove 7-2. On the lower surface of the inner cavity of the slider 7, there are clearance grooves equal in number to the U-shaped grooves 7-2 and corresponding in position to them. These clearance grooves provide clearance for the tail end of the flange bolts 4-6 after it extends beyond the nut 4-5, preventing interference. Multiple threaded holes adapted to the screws 7-3 are provided on the upper surface and the front and rear sides of the slider 7. The number of screws 7-3 is equal to the number of threaded holes. The screws 7-3 are placed in the threaded holes, restricting the vertical and horizontal freedom of the slider 7. See also... Figure 1 In this embodiment, three rows and three columns of nine threaded holes are provided on the upper surface of the slider 7 for screwing in screws 7-3, thereby fixing the slider 7 in the vertical direction and increasing the friction of the slider 7 in the horizontal direction, thus improving the stability during the experiment. In this embodiment, three threaded holes are provided on each of the front and rear sides of the slider 7 for screwing in screws 7-3, thereby fixing the slider 7 in the front and rear direction. In this embodiment, the diameter of the above-mentioned threaded holes is M8.

[0072] To facilitate the measurement of the displacement at the starting point of the wedge, when the axis of the leftmost track positioning through-hole 4-4 in the array of track positioning through-holes 4-4 is in the same vertical plane as the rightmost vertical end face of the wedge 5 and the starting position of the expansion section of the lower wall of the nozzle, the flange bolt 4-6 is positioned against the leftmost end of the U-shaped groove 7-2, and the axis of the flange bolt 4-6 is coaxial. In this embodiment, when the rightmost vertical end face of the wedge 5 and the starting position of the expansion section of the lower wall of the nozzle are in the same vertical plane, the left end face of the slider connecting plate 7-1 coincides with the right end face of the upper wall 1-1 of the combustion chamber. In this embodiment, when the axis of the rightmost track positioning through hole 4-4 in the array of the above-mentioned multiple track positioning through holes 4-4 is in the same vertical plane as the starting point of the above-mentioned wedge and the starting position of the expansion section of the lower wall of the nozzle, the flange bolt 4-6 is set at the leftmost end of the U-shaped groove 7-2, and the axis of the flange bolt 4-6 is coaxial.

[0073] See Figure 1 and Figure 5 In order to achieve better positioning, locking, and guiding effects, while keeping the structure simple and cost-effective, in this embodiment, the number of the above-mentioned track grooves 4-3 provided on the lower surface of each track 4-2, the number of the above-mentioned U-shaped grooves 7-2 provided on the upper surface of each slider 7 at the right end, and the number of the above-mentioned clearance grooves provided on the lower surface of the inner cavity of the slider 7 are all two; the above-mentioned slider fixing assembly includes two flange bolts 4-6 and two nuts 4-5; there are two sets of the above-mentioned slide rail slider assembly; the two sets of slide rail slider assembly are symmetrically arranged in the front and back direction along the combustion chamber 1.

[0074] See Figure 1 , Figure 7 as well as Figure 8 To facilitate replacement of the wedge, a wedge connecting plate 6-1 is fixedly connected to the right end of the upper wall surface 6 of the nozzle, and the surface of the wedge connecting plate 6-1 is perpendicular to the left-right direction. On the left side of the wedge connecting plate 6-1, at both the front and rear sides, there are nozzle upper wall positioning protrusions 6-2 protruding to the left for positioning and fitting when connected to the wedge 5. The wedge 5 is shaped by stretching a right-angled triangle perpendicular to the front-back direction along its axis. A wedge positioning groove 5-1, matching the nozzle upper wall positioning protrusion 6-2, is provided on the rightmost vertical end face of the wedge 5. The wedge 5 is detachably fixed to the left side of the upper wall surface 6 of the nozzle via the wedge connecting plate 6-1. In this embodiment, the wedge 5 is connected to the wedge connecting plate 6-1 by bolts, and the wedge 5 is replaceable. See also Figure 1 and Figure 7In order to ensure both strength and material conservation, reinforcing ribs are provided between the aforementioned wedge connecting plate 6-1 and slider connecting plate 7-1, and between the wedge connecting plate 6-1 and the upper wall surface 6 of the nozzle, in this embodiment.

[0075] The structures of the wedges 5 with different wedge angles connected to the wedge connecting plate 6-1 are completely identical. However, due to different wedge angles, according to trigonometric relationships, while ensuring that the height of the rightmost vertical surface of the wedge 5 remains constant in the vertical direction, the length of the upper horizontal surface of the wedge 5 in the horizontal direction is also different. When the wedges 5 in the device of this invention are replaced with wedges with wedge angles of 20°, 25°, and 30° commonly used in daily experiments, the lengths of the upper horizontal surface of the wedge 5 in the horizontal direction are 129mm, 100mm, and 81mm, respectively, and the length difference can be approximated as a multiple of 10mm. In this embodiment, in order to keep the starting position of the wedge unchanged when replacing the wedge 5, that is, to keep the relative position of the starting position of the wedge with respect to the starting position of the expansion section of the lower wall of the nozzle unchanged, the hole spacing of the above-mentioned multiple track positioning through holes 4-4 is preferably 10mm ± 0.2mm. In this embodiment, 10mm is used. This setup allows adjustment of the position of slider 7 relative to slide rail 4. Since the distance between adjacent track positioning through holes 4-4 on slide rail 4 in the left and right directions is 10mm, the single-variable experimental requirement of replacing wedge 5 without changing the wedge starting point can be achieved.

[0076] Before the experiment, the device of this embodiment of the invention, except for the sliding part, is first arranged according to... Figure 1 (To fully display its structure, Figure 1 (Screws 7-3, nuts 4-5, and flange bolts 4-6 are not installed on the slider 7 located on the rear side; these need to be installed in the actual experiment.) Next, connect the combustion chamber flange 2 to the front structure of the engine, such as the mixing section. Then, select a wedge 5 with a specific wedge angle according to the experimental requirements and connect the wedge 5 to the wedge connecting plate 6-1. Then, mount the sliding part composed of slider 7, nozzle upper wall 6, and wedge 5 onto the track 4-2. Next, determine the approximate position of the wedge starting point in the left-right direction according to the experimental requirements, place the nut 4-5 in the track groove 4-3, and set the flange bolt 4-6 against the leftmost end of the U-shaped groove 7-2, making the axis of the flange bolt 4-6 coaxial with the axis of the nearest track positioning through hole 4-4 and the nut 4-5, and screw in the flange bolt 4-6. Finally, screw screws 7-3 into the upper surface and front and rear sides of slider 7 to completely fix the sliding part.

[0077] In the experiment, if the goal is to study the relative position change between the starting point of the wedge and the starting position of the expansion section on the lower wall of the nozzle, i.e., to study the influence of the end of the confined space on the detonation wave, screw 7-3 can be loosened, nut 4-5 and flange bolt 4-6 can be removed, and slider 7 can be repositioned in the left and right directions according to the wedge starting point requirements. If the goal is to study the influence of the wedge angle on the detonation wave, the relative position of the wedge starting point with respect to the starting position of the expansion section on the lower wall of the nozzle must be fixed. Since the length of the horizontal plane above the wedge 5 changes in the left and right directions when the wedge angle of the wedge 5 changes between the commonly used 20°, 25° and 30°, it is approximately an integer multiple of 10mm. At the same time, in this embodiment of the invention, the spacing between adjacent track positioning through holes 4-4 in the left and right directions is 10mm. Therefore, it is only necessary to adjust the corresponding track positioning through holes 4-4 in the left and right directions of the U-shaped groove 7-2 to achieve single-variable control of the wedge angle change while the wedge starting point remains unchanged.

[0078] The inclined wedge slide rail device based on inclined detonation engine experiments of the present invention not only allows the inclined wedge starting point to be changed independently, but also provides the conditions for changing the inclined wedge angle independently; furthermore, for commonly used inclined wedge angles, the present invention provides an embodiment that can change both the inclined wedge starting point and the inclined wedge angle independently. The process of changing the inclined wedge starting point and the inclined wedge angle using the device of the present invention is simple and low in cost.

Claims

1. A slanted slide rail device based on slanted detonation engine experiments, characterized in that: It includes a combustion chamber (1), a nozzle, a wedge (5), and a slide rail slider assembly; The combustion chamber (1) has a cuboid shape and the left and right end faces of the cuboid are open; symmetrical observation windows (3) are provided on the front and rear walls of the combustion chamber (1); the left end of the combustion chamber (1) is used to connect with the mixing section. The nozzle is located on the right side of the combustion chamber (1) and the inner cavities of the two are connected; the two nozzle side walls (8-1) on the front and rear sides of the nozzle are fixedly connected to the nozzle lower wall (8-2) or the three are integrated, and the left ends of the three are respectively fixedly connected to the front and rear walls of the combustion chamber (1) and the right end of the combustion chamber lower wall (1-2); the nozzle lower wall (8-2) is inclined with the left side higher than the right side, and the intersection of the inner surface of the left end and the right end of the combustion chamber lower wall (1-2) is the starting position of the nozzle lower wall expansion section; the nozzle upper wall (6) is located between the two nozzle side walls (8-1) and is inclined with the left side lower than the right side. The wedge (5) is installed in the inner cavity of the combustion chamber (1) and the nozzle, and is detachably fixed to the left side of the upper wall (6) of the nozzle; the upper horizontal plane of the wedge (5) is tangent to the inner surface of the upper wall (1-1) of the combustion chamber (1), and the inclined surface of the wedge (5) intersects the upper horizontal plane of the wedge (5) at the left end of the wedge (5), which is the starting point of the wedge; In the slide rail and slider assembly, the slide rail (4) is fixedly installed on the outer upper surface of the upper wall (1-1) of the combustion chamber, and the slider (7) is fixedly connected to the outer upper surface of the upper wall (6) of the nozzle. The slider (7) can slide left and right along the slide rail (4). The slide rail slider assembly also includes a slider fixing assembly; The slide rail (4) includes a transition section (4-1) and a track (4-2) arranged sequentially from left to right; the track (4-2) is fixedly connected to the outer upper surface of the upper wall of the combustion chamber (1-1) through the transition section (4-1); the track (4-2) is a shape formed by stretching a track cross section perpendicular to the left and right direction along the axis of the left and right direction, and the shape of the track cross section is a first rectangle; The slider (7) is fixed to the outer upper surface of the nozzle upper wall (6) via a slider connecting plate (7-1); the slider (7) is a shape formed by stretching a slider cross-section perpendicular to the left and right direction along the axis of the left and right direction; the shape of the slider cross-section is that the inside is a second rectangle, and the outside is a shape formed by a third rectangle above and a trapezoid or fourth rectangle below, and the two lower vertices of the third rectangle above coincide with the two upper vertices of the trapezoid or fourth rectangle below; the size of the second rectangle inside the slider cross-section is adapted to the size of the track cross-section, and the slider (7) is fitted on the track (4-2); The slider fixing assembly is used to position and lock the slider (7) on the track (4-2); The slider fixing assembly includes at least two flange bolts (4-6), an equal number of nuts (4-5) adapted to the flange bolts (4-6), and a plurality of screws (7-3). At least two track grooves (4-3) are arranged in an array along the front-back direction on the lower surface of the track (4-2); the track grooves (4-3) extend in the left-right direction, and the cross-sectional dimensions of the track grooves (4-3) are adapted to the external dimensions of the nut (4-5); on the bottom plane of each track groove (4-3), a plurality of track positioning through holes (4-4) are arranged in an array along the left-right direction with the same starting position, hole spacing and number of holes, and the hole diameter of the track positioning through holes (4-4) is adapted to the radial dimension of the bolt of the flange bolt (4-6); On the upper surface of the slider (7), a U-shaped groove (7-2) with a U-shaped cross-section and the U-shaped opening facing to the right is provided at the right end. The number of U-shaped grooves (7-2) is equal to the number of track grooves (4-3), and their front-to-back position is adapted to the front-to-back position of track grooves (4-3). The U-shaped dimension of the U-shaped groove (7-2) is adapted to the radial dimension of the bolt of the flange bolt (4-6). The flange bolt (4-6) passes through the U-shaped groove (7-2) and the track positioning through hole (4-4) in sequence, and is connected to the nut (4-5) that is clamped in the track groove (4-3) to limit the degree of freedom of the slider (7) to slide left and right on the track (4-2); the lower surface of the inner cavity of the slider (7) is provided with a clearance groove equal in number to the U-shaped groove (7-2) and whose position corresponds to the position of the U-shaped groove (7-2). The clearance groove is used to make way for the tail end of the bolt (4-6) after it extends out of the nut (4-5); Multiple threaded holes adapted to the screws (7-3) are provided on the upper surface and the front and rear sides of the slider (7). The number of screws (7-3) is equal to the number of threaded holes. The screws (7-3) are set in the threaded holes, and the slider (7) is restricted in the vertical and horizontal directions and the front and rear directions by the screws (7-3).

2. The inclined slide rail device based on the inclined detonation engine experiment according to claim 1, characterized in that: The inner surfaces of the two nozzle sidewalls (8-1) are respectively coplanar with the corresponding inner surfaces of the front and rear walls of the combustion chamber (1).

3. The inclined slide rail device based on the inclined detonation engine experiment according to claim 1, characterized in that: When the rightmost vertical end face of the wedge (5) and the starting position of the expansion section of the lower wall of the nozzle are in the same vertical plane, the flange bolt (4-6) is set against the leftmost end of the U-shaped groove (7-2), and the axis of the flange bolt (4-6) is coaxial with the axis of the leftmost track positioning through hole (4-4) in the array of multiple track positioning through holes (4-4).

4. The inclined slide rail device based on the inclined detonation engine experiment according to claim 1, characterized in that: The spacing between the multiple track positioning through holes (4-4) is 10mm ± 0.2mm.

5. The inclined slide rail device based on the inclined detonation engine experiment according to claim 1, characterized in that: The number of track grooves (4-3) provided on the lower surface of each track (4-2), the number of U-shaped grooves (7-2) provided on the upper surface of each slider (7) at the right end, and the number of clearance grooves provided on the lower surface of the inner cavity of the slider (7) are all two. The slider fixing assembly includes two flange bolts (4-6) and two nuts (4-5). There are two sets of slide rail slider assemblies; the two sets of slide rail slider assemblies are symmetrically arranged in the front and back direction along the combustion chamber (1).

6. The inclined slide rail device based on the inclined detonation engine experiment according to claim 1, characterized in that: A wedge connecting plate (6-1) is fixedly connected to the right end of the upper wall surface (6) of the nozzle, and the plate surface of the wedge connecting plate (6-1) is perpendicular to the left and right directions; a nozzle upper wall positioning protrusion (6-2) is provided on the left side plate surface of the wedge connecting plate (6-1) at the front and rear sides, which is used for positioning and fitting when connected with the wedge (5); The wedge (5) is formed by stretching a right triangle perpendicular to the front and back direction along the axis of the front and back direction; a wedge positioning groove (5-1) is provided on the vertical end face of the rightmost end of the wedge (5) to match the positioning protrusion (6-2) on the upper wall of the nozzle. The wedge (5) is detachably fixed to the left side of the upper wall (6) of the nozzle via the wedge connecting plate (6-1).

7. The inclined slide rail device based on the inclined detonation engine experiment according to claim 1, characterized in that: The number of observation windows (3) provided on each of the front and rear walls of the combustion chamber (1) is one, and the front and rear walls of the combustion chamber (1) are served by the observation window frame (3-1) of the observation window (3).

8. The inclined slide rail device based on the inclined detonation engine experiment according to any one of claims 1 to 7, characterized in that: The combustion chamber (1) is provided with a combustion chamber flange (2) at its left end, which is connected to the mixing section.

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