Model surface real-time monitoring apparatus and method for arc heated duct testing

Abstract

The present application relates to arc heating test technical field, especially in a kind of for arc heating conduit test model surface real-time monitoring device, including rectangular nozzle, conduit and the model to be tested, the conduit is located in the one side of the rectangular nozzle and is communicated with it, the model to be tested is located in the upper portion of the conduit, is fixed by model block, the bottom of the conduit is equipped with endoscope module and cooling module for the cooling of endoscope module.The present application is cooled by the synergies of cooling module and endoscope module, and the clear imaging of model surface under high temperature and high pressure conditions in narrow area is realized using high-temperature-resistant endoscope module.Cooling module forms protective film on the surface of endoscope module, which can effectively prevent the baking of high-temperature gas flow and the erosion of various impurities in the gas flow, and the present application also provides a model surface real-time monitoring method for arc heating conduit test, which can obtain high-quality clear images.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of arc heating test, in particular to a model surface real-time monitoring device and method for arc heating duct test. BACKGROUND

[0002] At present, the development of hypersonic vehicles has become a front task for international aerospace powers to develop first. Hypersonic vehicles bring a series of research hot issues due to their extremely high speed. The material examination and structure design of thermal protection system are a very important branch field. The development of thermal protection system materials needs to study the physical and mechanical characteristics of special materials suitable for various application conditions, especially the ablation performance under high speed and high enthalpy conditions. The duct test under arc heating condition is a test technology suitable for the examination of protective materials under high enthalpy and high heat flux, and the test temperature is generally above 2000K or even higher.

[0003] Since the duct test is a model ablation test in a very narrow channel, various conventional test methods including video monitoring cannot be realized. For the test probe, the surface cold wall heat flux density and surface pressure can be directly measured by arranging measuring points thereon. For the real model, only the real-time measurement of back temperature can be realized. The conventional video monitoring camera cannot realize real-time observation of the ablation of the model surface due to the absence of an observation window. SUMMARY

[0004] The purpose of the present application is to provide a model surface real-time monitoring device for arc heating duct test, which can realize real-time observation of clear images of the model surface, and is of great significance for detailed understanding of the change characteristics of the model in the ablation test process.

[0005] The present application provides a model surface real-time monitoring device for arc heating duct test, comprising a rectangular nozzle, a duct and a model to be tested, the duct is arranged on one side of the rectangular nozzle and communicates with the rectangular nozzle, the model to be tested is arranged at the upper part of the duct and is fixed by a model pressing block, the bottom of the duct is provided with an endoscope module and a cooling module for cooling the endoscope module.

[0006] Preferably, the endoscope module comprises an endoscope, the endoscope passes through the bottom of the duct for observing the surface of the model to be tested, an observation window is arranged between the model to be tested and the endoscope, and the endoscope is connected with an image acquisition and processing system.

[0007] Preferably, the endoscope is fixed on the bottom of the duct through a fixing block, the fixing block is fixedly connected with the bottom of the duct, the fixing block is provided with a through hole, and the endoscope passes through the through hole and is connected with the through hole in interference.

[0008] Preferably, the observation window is made of sapphire glass, and the endoscope is a high-temperature endoscope capable of resisting high-temperature radiation.

[0009] Preferably, a plurality of endoscope modules are provided and uniformly distributed at the bottom of the catheter, and the distance between the observation windows is determined by the focal length and the field of view angle of the endoscope, so as to ensure that the field of view between adjacent observation windows is overlapped.

[0010] Preferably, the cooling module comprises a cooling pipeline for conveying a cooling gas flow and a jet pipe connected to the cooling pipeline, and the gas outlet end of the jet pipe is located above the observation window.

[0011] Preferably, the jet pipe is a rectangular jet pipe.

[0012] Preferably, the rectangular jet pipe forms an angle with the horizontal position of the observation window.

[0013] Preferably, the number of the cooling module is the same as that of the endoscope module, and each cooling module corresponds to one endoscope module.

[0014] Another object of the present application is to provide a model surface real-time monitoring method for arc heating catheter test, which is applied to the model surface real-time monitoring device for arc heating catheter test, and comprises the following steps:

[0015] (1) recording and storing the images of a plurality of small sub-regions of a plurality of models simultaneously by a high-definition camera connected to the rear end of the plurality of endoscope modules;

[0016] (2) correcting the distortion of each small sub-region image respectively;

[0017] (3) performing feature matching on the corrected small sub-region images and fusing them into one image, and finally storing the whole image and outputting it to a display device in real time.

[0018] Advantages:

[0019] The present application uses high-temperature-resistant endoscope modules to realize clear imaging of the model surface under high-temperature and high-pressure conditions in a narrow area through the synergistic effect of the cooling module and the endoscope module. The cooling module forms a protective gas film on the surface of the endoscope module, which can effectively prevent the baking of high-temperature gas flow and the erosion of various impurities in the gas flow.

[0020] The improved image distortion calibration technology based on target centroid is used to correct the images imaged by the endoscope, so as to obtain high-quality clear images. The image matching and fusion technology is used to match and integrate the small-area model images. The large-area model image is displayed and stored in real time. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the specific embodiments or the prior art of the present application, the drawings needed to be used in the description of the specific embodiments or the prior art will be briefly introduced as follows. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0022] Fig. 1 Schematic diagram of the device of the present application;

[0023] Fig. 2 Schematic diagram of the cooling module and the endoscope module in the present application;

[0024] Fig. 3 Top view of the positional relationship between the rectangular jet pipe and the observation window in the present application.

[0025] Legend: 1-rectangular jet pipe, 2-catheter, 3-model to be tested, 4-endoscope module, 5-cooling module, 6-model pressing block, 401-endoscope, 402-observation window, 403-fixing block, 404-image acquisition and processing system, 501-rectangular jet pipe, 502-cooling pipe, 503-cooling gas flow. DETAILED DESCRIPTION

[0026] The technical solutions of the present application will be described in detail below in conjunction with the embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without any creative effort belong to the scope of protection of the present application.

[0027] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0028] Furthermore, the terms "first", "second", "third", etc. are used herein for descriptive purposes only and should not be construed as indicating or implying relative importance or an ordered sequence. Thus, features defined with "first", "second" or "third" can include one or more of the features. In the description of the application, the meaning of "a plurality" is two or more, unless explicitly specified otherwise. Furthermore, the terms "mounting", "connected", "connecting" should be interpreted broadly, for example, can be fixed connection, can also be detachable connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0029] Embodiment 1

[0030] A model surface real-time monitoring device for arc heating duct test, as shown in Figs. 1-3 Fig. 1, comprising a rectangular nozzle 1, a duct 2 and a model to be tested 3, the duct 2 is arranged on one side of the rectangular nozzle 1 and communicates with it, the model to be tested 3 is arranged on the upper part of the duct 2 and is fixed by a model pressing block 6, and the bolts pass through the model pressing block 6, the model to be tested 3 and the outer side of the duct 2 in sequence to complete the fixing. The bottom of the duct 2 is provided with an endoscope module 4 and a cooling module 5 for cooling the endoscope module 4. During the arc heating duct test, the test flow passes through the rectangular nozzle 1 and then flows through the surface of the model to be tested 3, so as to test and evaluate the model to be tested.

[0031] The endoscope module 4 comprises an endoscope 401, the endoscope 401 passes through the bottom of the duct 2 for observing the surface of the model to be tested, and an observation window 402 is arranged between the model to be tested 3 and the endoscope 401. The endoscope 401 is connected with an image acquisition and processing system 404, and the image acquisition and processing system 404 collects the real-time state of the model surface through the endoscope module 4. The endoscope 401 is fixed on the bottom of the duct 2 through a fixing block 403, the fixing block 403 is fixedly connected with the bottom of the duct 2, the fixing block 403 is provided with a through hole, and the endoscope 401 passes through the through hole and is connected with it in interference, so as to adjust the front and rear installation positions of the endoscope 401 to adapt to different focal lengths and field angles.

[0032] The observation window 402 is made of sapphire glass, which is processed into a window glass with excellent light transmission performance and high temperature resistance after high temperature resistance treatment. The observation window 402 can resist the erosion of 2000K high temperature airflow, and the endoscope 401 is a high temperature endoscope that can resist high temperature radiation. During the duct test, part of the high temperature energy will be radiated to the position of the endoscope 401. The characteristic of the endoscope that can resist high temperature can resist these energies and can ensure the normal work of the endoscope.

[0033] The endoscope module 4 is provided with multiple, evenly distributed on the bottom of the duct 2, the distance between the observation windows 402 is set by the focal length and field of view angle of the endoscope 401, to ensure that the field of view between each adjacent observation window 402 is mutually overlapping.

[0034] The cooling module 5 includes a cooling pipeline 502 for delivering cooling airflow and a rectangular jet pipe 501, which is designed with a narrowed middle part. The cooling pipeline 502 is connected to the rectangular jet pipe 501, and the outlet end of the rectangular jet pipe 501 is located above the observation window 402. The rectangular jet pipe 501 can spray a thin film of high-pressure airflow, thereby forming a protective gas film on the surface of the observation window 402, protecting the observation window 402 from being directly baked and washed by high-temperature and high-enthalpy airflow. The outlet direction of the rectangular jet pipe 501 forms an angle with the horizontal position of the observation window 402, to ensure that the action area of the cooling airflow is only near and downstream of the observation window 402. The cooling module 5 has the same number as the endoscope module 4 and corresponds one-to-one.

[0035] A model surface real-time monitoring method for arc heating duct test, the method is applied to the model surface real-time monitoring device for arc heating duct test, and the method comprises the following steps:

[0036] (1) Simultaneously record and store multiple small sub-area images of multiple models through the high-definition camera connected to the rear end of the multiple endoscope modules;

[0037] (2) Correct the distortion of each small sub-area image respectively;

[0038] (3) Perform feature matching on the corrected small sub-area images and fuse them into one image, and finally store the overall image and output it in real time to the display device.

[0039] Working and using process:

[0040] The first step is to design and process four observation window mounting holes on the front surface of the duct, that is, the inner surface of the airflow passage; the holes are step structures for mounting the observation windows on the steps; the holes close to the inner wall surface are M8*0.5 fine thread holes for mounting and fixing the observation window pressing blocks; the four observation windows are evenly distributed, and the distance between them is 20 mm, to ensure that each adjacent endoscope has a partially overlapping field of view.

[0041] The second step is to fix the endoscope to the endoscope fixing block, and then install the fixing block on the duct, so that the front end of the lens of the endoscope maintains a certain distance from the observation window glass, to avoid being directly affected by the incoming flow temperature; at the same time, the front and rear installation positions of the endoscope can be adjusted to adapt to endoscopes with different focal lengths and field of view angles.

[0042] Third step is to design and process a cooling airflow hole outside the small hole of the catheter observation window; here the side refers to the direction of the flow, the cooling airflow hole is upstream of the small hole of the observation window; the cooling airflow hole is designed as a rectangular nozzle to form a rectangular air film and then form a protective film above the observation window.

[0043] Fourth step is to design the flow direction channel of the cooling airflow and the observation window at a certain angle to ensure that the action area of the cooling airflow is only near the observation window and downstream.

[0044] Fifth step is to use a high-definition camera to connect the rear interface of the endoscope, record and store the model image of the endoscope imaging.

[0045] Sixth step is to use the improved image distortion correction model based on target centroid to evaluate and correct the recorded image with distortion.

[0046] Seventh step is to use the image matching technology to extract the key features of the overlapping part of the four images and match them two by two.

[0047] Eighth step is to use the image fusion technology to further process the image seam details and the brightness uniformization of multiple images of the matched images to obtain a clear and true large-area model image.

[0048] Ninth step is to use the remote transmission technology to put the fused complete image on the display large screen in the arc heating control room and store it on the storage device.

[0049] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A model surface real-time monitoring device for arc heated duct testing, characterized by, The device comprises a rectangular nozzle, a guide pipe and a model to be tested, the guide pipe is arranged on one side of the rectangular nozzle and communicates with the rectangular nozzle, the model to be tested is arranged on the upper part of the guide pipe and is fixed by a model block, the bottom of the guide pipe is provided with an endoscope module and a cooling module for cooling the endoscope module, the endoscope module comprises an endoscope, the endoscope passes through the bottom of the guide pipe for observing the surface of the model to be tested, an observation window is arranged between the model to be tested and the endoscope, the endoscope is connected with an image acquisition and processing system, the endoscope is fixed on the bottom of the guide pipe through a fixing block, the fixing block is fixedly connected with the bottom of the guide pipe, the fixing block is provided with a through hole, the endoscope passes through the through hole and is connected with the through hole in an interference fit, a plurality of endoscope modules are arranged on the bottom of the guide pipe and are uniformly distributed, the distance between the observation windows is determined by the focal length and the field angle of the endoscope, so that the field of view of each adjacent observation window is overlapped, the cooling module comprises a cooling pipeline for conveying cooling gas and a jet pipe, the cooling pipeline and the jet pipe are connected, the jet pipe is located above the observation window, the jet pipe is a rectangular jet pipe, the middle of the rectangular jet pipe is narrowed, and the jet pipe forms an angle with the horizontal position of the observation window.

2. The model surface real-time monitoring device for arc heated catheter testing of claim 1, wherein, The observation window is made of sapphire glass, and the endoscope is a high-temperature endoscope capable of resisting high-temperature radiation.

3. The model surface real-time monitoring device for arc heated catheter testing of claim 1, wherein, The number of the cooling module is the same as that of the endoscope module, and they are one-to-one corresponding.

4. A method for real-time monitoring of a model surface for arc heated cathode test, characterized in that, The method is applied to the model surface real-time monitoring device for arc heating guide pipe test according to any one of claims 1-3, and the method comprises the following steps: (1) simultaneously recording and storing multiple small sub-area images of multiple models by a high-definition camera connected with the rear ends of the multiple endoscope modules; (2) correcting the distortion of each small sub-area image respectively; (3) performing feature matching on the corrected small sub-area images and fusing them into one image, and finally storing the whole image and outputting it to a real-time display device.

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