A model system for heavy model free flight aerodynamic measurement test

Abstract

The present invention relates to the technical field of wind tunnel testing, and in particular to a model system for a heavy model free-flight aerodynamic measurement test, wherein the model body is divided into two sections, an accelerometer is provided in each section, and two mass blocks are spaced apart in the model body, an adjustment mechanism is provided between the two mass blocks, and a spacing is provided between the adjustment mechanism and the two mass blocks. The accelerometer is provided in the slide of the adjustment mechanism, and the position of the accelerometer is adjusted by adjusting the position of the slide. The center of mass of the model system can be adjusted by replacing mass blocks of different weights. In addition, the center of mass of the model system can be fine-tuned by moving the slide, and the center of mass of the model system can also be adjusted by cooperating with the mass blocks. The model system performs aerodynamic measurement by measuring acceleration, has a compact overall structure, and the position of the accelerometer is adjustable, and the center of mass of the model system is adjustable, and can be applied to different measurement accuracy requirements and different tests.

Description

Technical Field

[0001] The invention relates to the technical field of wind tunnel testing, and in particular to a model system for a heavy model free-flight aerodynamic measurement test. Background Art

[0002] The aerodynamic measurement process in shock tunnels is complex, involving a wide range of phenomena with complex mechanisms. It is a global challenge, and currently no unified and effective testing method has been developed. Judging from the progress of technological development, shock tunnel aerodynamic measurement technology is at a watershed in the field of segmentation. On the one hand, the existing tail balance force measurement technology has evolved from high-speed wind tunnel force measurement technology. On the other hand, there has been no effective improvement to meet the unique application requirements of shock tunnels. In the field of hypersonic aerodynamic measurement, conventional hypersonic wind tunnels, low-density hypersonic wind tunnels, pulse combustion wind tunnels and other equipment can all use static principles to achieve aerodynamic measurement due to their long effective test time (on the order of hundreds of milliseconds to tens of seconds). However, the millisecond-level effective test process of shock tunnels is a dynamic test process, and the dynamic principle is more appropriate.

[0003] The heavy model free-flight force measurement technology is to place the model in a free-fall state during the test, install an accelerometer inside the model, and when the aerodynamic force acts on the model, the acceleration generated is sensed and collected by the accelerometer, and finally the aerodynamic force is obtained by inverse calculation. The key to the heavy model free-flight force measurement technology is to design reasonable model inertia parameters based on the expected value of the aerodynamic load, so that the attitude change angle of the model can be ignored within a very short effective time, thereby meeting the test premise that the model attitude remains unchanged. The form of model free flight breaks the traditional strut support test method. The force measurement system becomes more compact and can easily reach a natural frequency of thousands of hertz, which can better match the effective test time requirements of hundreds of microseconds.

[0004] The existing model structure for measurement using an internally set accelerometer, for example, the Chinese patent application with publication number CN110108439A, does not involve the position adjustment of the accelerometer and the adjustment of the model's center of mass. After the model is assembled, the various parameters are fixed, and the adjustment of the model's center of mass and the accelerometer position cannot be achieved. As the level of non-destructive recycling of heavy models continues to improve, the model may be reused to obtain different test data. For different tests and higher measurement accuracy requirements, it is necessary to make certain adjustments to the model's accelerometer position and some of the model's center of mass. However, since the model is generally the same as the real thing or is made after being scaled down, the various parameter requirements are relatively high. Therefore, how to achieve the adjustment of the model's center of mass and the accelerometer position while ensuring that the requirements are met is a problem that those skilled in the art need to solve. Summary of the Invention

[0005] The purpose of the present invention is to provide a model structure for heavy model free flight aerodynamic measurement test with adjustable accelerometer position and model center of mass.

[0006] To achieve the above-mentioned object, the present invention provides a model system for a heavy model free-flight aerodynamic measurement test, comprising a model body, wherein the model body comprises a first model section and a second model section, wherein the first model section and the second model section are connected by a threaded stop, and a cavity is provided in each of the first model section and the second model section;

[0007] An accelerometer is provided inside the cavity of the first model section;

[0008] The cavity of the second model segment is provided with a first mass block, an adjustment mechanism, a second mass block, and a model end cap in order from the direction toward the first model segment to the direction away from the first model segment. The first mass block and the second mass block are both detachably fixed in the cavity of the second model segment. A gap is provided between the adjustment mechanism and the first mass block and the second mass block. At least one accelerometer is provided in the slide cylinder of the adjustment mechanism, and the position of the slide cylinder in the axial direction of the model body can be adjusted by operation. The model end cap is provided at the end of the second model segment.

[0009] Each accelerometer is located on the axis of the model body;

[0010] The first mass block is provided with a first wire hole passing through the first mass block along the axial direction of the model body, and a data collector is embedded in the second mass block. The cable of the accelerometer located in the first model section is connected to the data collector after passing through the first wire hole and the slide cylinder, and the cable of the accelerometer located in the second model section is led out from the slide cylinder and connected to the data collector.

[0011] Optionally, positioning grooves are respectively provided on the side walls of the overlapping portion where the first model segment and the second model segment are connected. When the first model segment and the second model segment are connected in place, the two positioning grooves overlap.

[0012] Optionally, the first mass block is in the shape of a truncated cone, and a corresponding position in the cavity of the second model segment has a conical surface matching the first mass block;

[0013] A clamping cover is provided at the large end of the first mass block, and a second wire passing hole coaxial with the first wire passing hole is provided on the clamping cover. A first single-layer wave spring is provided between the clamping cover and the first mass block. The clamping cover is fixed in the cavity of the second model section by a threaded connection. The pre-tightening force of the first single-layer wave spring on the first mass block can be adjusted by rotating the clamping cover.

[0014] Optionally, a groove is provided on the end surface of the pressing cover that contacts the first single-layer wave spring, the first single-layer wave spring is located in the groove, and the side wall of the groove is an inclined surface.

[0015] Optionally, an embedding hole is provided on the second mass block along the axial direction of the model body and passes through the second mass block, and the data collector is installed in the embedding hole;

[0016] A perspective window sealed with transparent material is provided on the end cover of the model for observing the indicator light of the data collector.

[0017] Optionally, the second mass block is provided with at least one conical section at one end facing the first mass block, and a conical surface matching the conical section is provided at a corresponding position in the cavity of the second model section. A second single-layer wave spring is provided between the model end cover and the second mass block, and the model end cover presses the second single-layer wave spring, thereby providing preload force to the second mass block through the second single-layer wave spring.

[0018] Optionally, an annular groove is provided on the outer peripheral side of one end of the second mass block facing the model end cover, so that a receiving groove is formed between the second mass block and the model end cover, the bottom surface of the receiving groove is an inclined surface, and the second single-layer wave spring is located in the receiving groove.

[0019] Optionally, a copper gasket is provided in the accommodating groove, and the copper gasket is located between the second single-layer wave spring and the second mass block, and is used to adjust the compression gap of the second single-layer wave spring.

[0020] Optionally, two accelerometers are provided in the slide cylinder of the adjustment mechanism, and the two accelerometers are coaxially arranged, wherein the accelerometer in the cavity close to the first model section is located at the center of mass of the model system.

[0021] Optionally, the adjustment mechanism further includes a mounting seat, a thrust bearing, a clamping ring and a support ring, wherein the mounting seat, the thrust bearing, the clamping ring and the support ring are all coaxially arranged with the model body, and the thrust bearing is located between the mounting seat and the clamping ring;

[0022] The slide is provided with an external thread, and at least two axial sliding planes are provided at intervals along the circumferential direction on the outer side of the slide, so that the external thread is divided into multiple sections in the circumferential direction of the slide. At least one mounting plane is provided inside the slide for mounting the accelerometer.

[0023] The mounting seat is fixedly mounted in the cavity of the second mold section, and the mounting seat is annular. The inner hole wall of the mounting seat is provided with an axial guide plane matching the axial sliding plane. The slide cylinder is passed through the mounting seat, and the axial sliding plane is arranged in contact with the axial guide plane.

[0024] The outer circumference and inner side of the clamping ring are both provided with threads, and the clamping ring is connected to the cavity of the second mold section through threads;

[0025] The outer circumference and inner side of the support ring are both provided with threads. The support ring is arranged on the inner side of the clamping ring and is threadedly connected to the clamping ring. The support ring is sleeved on the outer side of the slide and is threadedly connected to the slide.

[0026] Optionally, a keyway is provided in the cavity of the second mold section along the axial direction of the mold body;

[0027] The outer side of the mounting seat is provided with a key that matches the keyway.

[0028] Optionally, the adjustment mechanism further comprises two locking rings;

[0029] An internal thread is provided on the inner side of the locking ring, which is sleeved on the outer side of the slide and connected to the slide thread. The two locking rings are respectively located at the two ends of the mounting seat. The two locking rings are rotated so that the two locking rings are against the two ends of the mounting seat to fix the position of the slide.

[0030] The above technical solution of the present invention has the following advantages: the model system for the free-flying aerodynamic measurement test of a heavy model provided by the present invention has a model body divided into two sections, an accelerometer is set in each section, and two mass blocks are set at intervals in the model body, an adjustment mechanism is provided between the two mass blocks, and a gap is provided between the adjustment mechanism and the two mass blocks to reserve space for the adjustment of the adjustment mechanism. The accelerometer is set in the slide of the adjustment mechanism, and the position of the accelerometer is adjusted by adjusting the position of the slide, thereby achieving more accurate measurement and meeting the requirements of different tests. By replacing mass blocks of different weights, the center of mass of the model system is adjusted. In addition, the center of mass of the model system can be fine-tuned by moving the slide, and the center of mass of the model system can also be adjusted by cooperating with the mass blocks. The model system performs aerodynamic measurement by measuring acceleration, and the overall structure is compact, the position of the accelerometer is adjustable, and the center of mass of the model system is adjustable, which can be applied to different measurement accuracy requirements and different tests. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings of the present invention are provided for illustrative purposes only, and the proportions and quantities of the components in the drawings may not necessarily be consistent with the actual product.

[0032] Figure 1 1 is a schematic structural diagram of a model system for a heavy model free flight aerodynamic measurement test in an embodiment of the present invention;

[0033] Figure 2 yes Figure 1 A schematic cross-sectional view of the middle model system cut through the axis of the model body;

[0034] Figure 3 yes Figure 2 A magnified schematic diagram of part A in FIG;

[0035] Figure 4 yes Figure 2 A magnified schematic diagram of part B in FIG.

[0036] Figure 5 yes Figure 2 Schematic cross-section of the CC position of the middle model system;

[0037] Figure 6 is a schematic diagram of an adjustment mechanism in an embodiment of the present invention;

[0038] Figure 7 yes Figure 6 A structural diagram of the middle adjustment mechanism from another angle;

[0039] Figure 8 yes Figure 1 Schematic diagram of the structure of the middle model system after removing the second model segment;

[0040] Figure 9 is a structural schematic diagram of a second model segment in an embodiment of the present invention;

[0041] Figure 10 yes Figure 9 Another perspective structural diagram of the second model segment;

[0042] Figure 11 yes Figure 9 A schematic cross-sectional view of the second model section taken through the axis;

[0043] Figure 12 This is a schematic structural diagram of a compression cover according to an embodiment of the present invention;

[0044] Figure 13 Schematic diagram of another adjustment mechanism in an embodiment of the present invention.

[0045] In the picture:

[0046] 1: Model ontology;

[0047] 11: first model segment;

[0048] 12: Second model segment;

[0049] 121: keyway;

[0050] 13: positioning slot;

[0051] 2: accelerometer;

[0052] 3: first mass block;

[0053] 31: First wire hole;

[0054] 32: Press the cover;

[0055] 321: second cable hole;

[0056] 322: groove;

[0057] 4: Adjustment mechanism;

[0058] 41: slide;

[0059] 411: axial sliding plane;

[0060] 412: Installation plane;

[0061] 42: mounting seat;

[0062] 421: axial guide plane;

[0063] 422: key;

[0064] 43: thrust bearing;

[0065] 44: compression ring;

[0066] 45: support ring;

[0067] 46: locking ring;

[0068] 5: second mass block;

[0069] 51: data collector;

[0070] 52: receiving slot;

[0071] 6: Model end cap;

[0072] 61: perspective window;

[0073] 7: The first single-layer wave spring;

[0074] 8: Second single-layer wave spring;

[0075] 9: Copper gasket. DETAILED DESCRIPTION

[0076] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0077] In addition, the terms “first” and “second” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0078] See also Figures 1 to 5 As shown, the model system for the heavy model free flight aerodynamic measurement test provided by the present invention includes a model body 1, three accelerometers 2, a first mass block 3, an adjustment mechanism 4, a second mass block 5 and a model end cover 6.

[0079] See Figure 1 and Figure 2As shown, the model body 1 includes a first model segment 11 and a second model segment 12. The segmented design facilitates the installation of the internal structure. The first and second model segments 11, 12 are connected by a threaded stop structure, which facilitates the connection between the segmented model segments and effectively ensures the connection strength. Both the first and second model segments 11, 12 have cavities. When the first and second model segments 11, 12 are connected, the cavities within them are connected.

[0080] See also Figure 2 As shown, an accelerometer 2 is provided inside the cavity of the first mold section 11. The first mass block 3, the adjustment mechanism 4, the second mass block 5 and the mold end cover 6 are arranged in the cavity of the second mold section 12, and are arranged from the direction toward the first mold section 11 to the direction away from the first mold section 11 ( Figure 2 The first mass 3 and the second mass block 5 are arranged in sequence (from left to right in the middle), and the first mass 3 and the second mass block 5 are both detachably fixed in the cavity of the second model section 12, which is convenient for replacing mass blocks of different masses. There is a gap between the adjustment mechanism 4 and the first mass block 3 and the second mass block 5, which reserves space for the adjustment of the adjustment mechanism 4. The adjustment mechanism 4 includes at least one slide 41. The slide 41 can move relative to the model body 1 along the axial direction of the model body 1. At least one accelerometer 2 is provided in the slide 41. The position of the slide 41 in the axial direction of the model body 1 can be adjusted by operation (for example, rotation, linear push), and the model end cover 6 is provided at the end of the second model section 12 to close the cavity of the model body 1.

[0081] Each accelerometer 2 in the model body 1 is located on the axis of the model body 1 , and each accelerometer 2 is coaxially arranged.

[0082] The first mass block 3 is provided with a first wire hole 31 extending axially through the model body 1. The second mass block 5 is provided with an embedding hole extending axially through the model body 1 for embedding a data collector 51. The cables of the accelerometers 2 located in the first model section 11 are connected to the data collector 51 after passing through the first wire hole 31 and the slide 41. The cables of the accelerometers 2 located in the second model section 12 are extended from the slide 41 and connected to the data collector 51, thereby collecting the output data of each accelerometer 2.

[0083] In the model system of this embodiment, the model body 1 is divided into two sections, an accelerometer is set in each section, and two mass blocks are set at intervals in the model body, an adjustment mechanism 4 is provided between the two mass blocks, and a gap is provided between the adjustment mechanism 4 and the two mass blocks to reserve space for the adjustment of the adjustment mechanism 4. The accelerometer is set in the slide 41 of the adjustment mechanism, and the position of the accelerometer is adjusted by adjusting the position of the slide, so as to achieve more accurate measurement and meet the requirements of different tests. By replacing mass blocks of different weights, the center of mass of the model system is adjusted. In addition, the center of mass of the model system can be fine-tuned by moving the slide, and the center of mass of the model system can also be adjusted by cooperating with the mass blocks. The model system performs aerodynamic measurement by measuring acceleration. The overall structure is compact, the position of the accelerometer is adjustable, and the center of mass of the model system is adjustable. It can be applied to different measurement accuracy requirements and different tests.

[0084] In one embodiment, see Figure 1 and Figure 2 As shown, the model body 1 is a cone, in which three accelerometers 2 are arranged. One accelerometer 2 is arranged in the cavity of the first model section 11, and is mainly used for pitch moment measurement. The other two accelerometers 2 are arranged in the second model section 12 and are located in the slide 41 of the adjustment mechanism 4 and are fixed by bonding. One of the accelerometers 2 is set at the center of mass of the model system to avoid the influence of other components. Another accelerometer 2 is set to the right of the accelerometer 2 at the center of mass, and is mainly used for pitch component measurement. The three accelerometers 2 are coaxially arranged. Since the slide 41 can be adjusted, the relative positions of the two accelerometers 2 in the slide 41 in the axial direction of the model body 1 can be fixed according to the test and are not limited here.

[0085] It should be noted that accelerometer 2 is installed at the center of mass of the model system. Due to factors such as inevitable manufacturing errors and differences in material density parameters, the final center of mass of the model system may deviate from the designed value. Furthermore, when pursuing higher precision, it is necessary to consider that the position of the accelerometer's electric core does not necessarily coincide with the accelerometer's centroid. Therefore, an adjustable accelerometer is required. This allows calibration and other methods to determine the relative axial distance between the accelerometer's electric core and the model's center of mass, allowing adjustment to bring them into alignment. The adjustable accelerometer of the model system of the present invention can address this issue.

[0086] It is worth noting that the ability to adjust the position of the slide 41 in the axial direction of the model body 1 through operation means that, according to the structure of the adjustment mechanism 4, the slide 41 can be moved axially along the model body 1 through corresponding operation. For example, if the slide 41 is installed in a track and moves along the track, the "operation" at this time is to push (if there is a limit, first release the limit and then push) the slide 41. For another example, if the slide 41 is installed and connected by a thread, at this time, the "operation" is to rotate the slide 41. In the above two examples, both the track and the threaded connection are mature structures and will not be described in detail here.

[0087] In order to ensure that the first model segment 11 and the second model 12 are in the same position each time they are installed, the Y sensitive axis of the accelerometer is ensured to be parallel to the normal direction. In some embodiments, see Figures 9 to 11 As shown, positioning grooves 13 are provided on the sidewalls of the overlapping portion where the first and second mold segments 11 and 12 meet. Once the first and second mold segments 11 and 12 are connected, the two positioning grooves 13 align, ensuring consistent connection positions during each installation. During installation, a positioning block with a shape matching the positioning grooves 13 can be used to ensure alignment of the two positioning grooves 13. Specifically, first tighten the first and second mold segments 11 and 12. At this point, the two positioning grooves 13 may be slightly offset. A positioning block with a push rod connected to one end is then pushed into the positioning groove 13. If the positioning grooves 13 of the first and second mold segments 11 and 12 are not aligned, increasing thrust will cause the first and second mold segments 11 and 12 to rotate relative to each other, causing the two positioning grooves 13 to align, ensuring consistent installation positions for each of the first and second mold segments 11 and 12. The positioning block can then be removed. Of course, other similar structures can also be used for positioning, which is not limited here. Preferably, the positioning grooves 13 are grooves with a guiding effect, such as V-shaped grooves or wedge-shaped grooves.

[0088] In some embodiments, see Figure 2 and Figure 3As shown, the first mass block 3 is truncated cone-shaped, and the corresponding position in the cavity of the second model section 12 has a conical surface that matches the first mass block 3. After the first mass block 3 is installed in place, the outer peripheral surface of the first mass block 3 is tightly attached to the conical surface in the cavity of the second model section 12, and the taper of the conical surface is used to achieve axial limitation. In order to further prevent the first mass block 3 from moving in the opposite direction of the axial limit direction of the conical surface of the first mass block 3, a clamping cover 32 is provided at the large end of the first mass block 3, and a second wire hole 321 coaxial with the first wire hole 31 is provided on the clamping cover 32, and a first single-layer wave spring 7 is provided between the clamping cover 32 and the first mass block 3. The clamping cover 32 is fixed in the cavity of the second model section by a threaded connection. The pre-tightening force of the first single-layer wave spring 7 on the first mass block 3 can be adjusted by rotating the clamping cover 32, which not only prevents the first mass block 3 from moving in the axial direction, but also has sufficient pre-tightening force after being clamped by the clamping cover 32, thereby avoiding shaking of the first mass block 3 during the test, thereby affecting the test results.

[0089] See also Figure 3 and Figure 12 As shown, in some preferred embodiments, to ensure that the first single-layer wave spring 7 is always in the ideal position, a groove 322 is formed on the end surface of the compression cover 32 that contacts the first single-layer wave spring 7. The first single-layer wave spring 7 is positioned within the groove 322. The groove wall is designed as an inclined surface, which effectively solves the problem of radial expansion of the first single-layer wave spring 7 under pressure. In one specific embodiment, the groove wall is inclined from the bottom of the groove 322 to the groove mouth.

[0090] In order to make the overall structure of the model system more compact, in some embodiments, see Figure 2 and Figure 4 As shown, the second mass block 5 is provided with an embedding hole extending through the axial direction of the model body 1, and the data collector 51 is installed in the embedding hole. The model end cap 6 is provided with a transparent material-enclosed perspective window 61 for observing the indicator light of the data collector 51, conveniently monitoring whether the data collector 51 is working properly.

[0091] In order to facilitate the positioning and installation of the second mass 5, in some embodiments, see Figure 2 and Figure 8 As shown, the left end of the second mass 5 is a conical section, that is, the outer side of the left end is a conical surface. The corresponding position in the cavity of the second mold section 12 has a conical surface that matches the conical section, achieving axial positioning of the second mass 5. Similarly, to prevent the second mass 5 from shaking during testing, a second single-layer wave spring 8 is installed between the mold end cover 6 and the second mass 5. The mold end cover 6 compresses the second single-layer wave spring 8, which provides preload force for the second mass 5.

[0092] In some embodiments, see Figure 2 and Figure 4 As shown, an annular groove is provided on the outer peripheral side of one end of the second mass block 5 facing the model end cover 6 (i.e., a portion of the outer wall of the second mass block 5 is cut off axially from the end face of the end, so that the diameter of the end becomes smaller, forming a type of step-like structure). When the model end cover 6 presses the second mass block 5, the side of the model end cover 6 facing the second mass block 5 serves as a groove side wall (accommodation groove), so that an accommodation groove 52 is formed between the second mass block 5 and the model end cover 6. The second single-layer wave spring 8 is located in the accommodation groove 52, so that it is always handled in a relatively ideal position. In order to better solve the problem of radial expansion of the second single-layer wave spring 8 after being compressed, the bottom surface of the accommodation groove 52 is an inclined surface. In a specific embodiment, the inclined surface of the groove bottom is inclined in a contraction direction from the side away from the model end cover 6 to the model end cover 6.

[0093] In order to better adjust the compression gap, in some embodiments, a copper gasket 9 is set in the accommodating groove 52, and the copper gasket 9 is located between the second single-layer wave spring 8 and the second mass block 5, for adjusting the compression gap of the second single-layer wave spring 8.

[0094] In some embodiments, see Figure 2 、 Figure 6 and Figure 7 As shown, the adjustment mechanism 4 includes a slide 41, a mounting seat 42, a thrust bearing 43, a clamping ring 44, a support ring 45, and two locking rings 46. The mounting seat 42, the thrust bearing 43, the clamping ring 44, and the support ring 45 are all coaxially arranged with the model body 1. The thrust bearing 43 is located between the mounting seat 42 and the clamping ring 44, which eliminates most of the circumferential friction generated during the clamping process, allowing the clamping ring 44 to provide a relatively pure axial clamping force.

[0095] The slide 41 is provided with an external thread, and at least two axial sliding planes 411 are provided at intervals along the circumferential direction on the outer side of the slide 41, for example, two, three, or four, so that the external thread is divided into multiple sections in the circumferential direction of the slide 41. At least one mounting plane 412 is provided inside the slide 41 to provide a flat mounting surface, which is convenient for the precise installation of the accelerometer 2.

[0096] The mounting seat 42 is fixedly mounted in the cavity of the second mold section 12, and the mounting seat 42 is annular. The inner hole wall of the mounting seat 42 is provided with an axial guide plane 421 that matches the axial sliding plane 411 (see Figure 13 As shown), the slide 41 is inserted into the mounting seat 42, and the axial sliding plane 411 is fitted with the axial guide plane 421, so that the slide 41 can slide relative to the mounting seat 42 along the axial direction of the model body 1 under better positioning.

[0097] The outer circumference and inner side of the clamping ring 44 are both provided with threads, and the clamping ring 44 is connected to the cavity of the second mold section 12 through the threads.

[0098] The outer and inner sides of the support ring 45 are both provided with threads, see Figure 2 and Figure 7 As shown, the support ring 45 is arranged on the inner side of the clamping ring 44 and is threadedly connected to the clamping ring 44 . The support ring 45 is sleeved on the outer side of the slide cylinder 41 and is threadedly connected to the slide cylinder 41 .

[0099] An internal thread is provided on the inner side of the locking ring 46, and it is sleeved on the outer side of the slide 41 and threadedly connected to the slide 41. The two locking rings 46 are respectively located at the two ends of the mounting seat 42. The two locking rings 46 are rotated so that the two locking rings 46 are against the two ends of the mounting seat 42 to fix the position of the slide 41. On this basis, the main function of the support ring 45 is to increase the axial support fixing point of the slide 41.

[0100] In another embodiment, see Figure 13 As shown, the adjustment mechanism 4 is not provided with a locking ring 46 , and the left end is slidably connected to the axial guide plane 421 through the axial sliding plane 411 , and the right end is supported and fixed by the support ring 45 , which also limits the axial position of the slide cylinder 41 .

[0101] The mounting base 42 can be connected to the second mold section 12 by threads. In some embodiments, see Figure 2 、 Figure 5 and Figure 10 As shown, the mounting seat 42 is connected to the second mold section 12 by a key connection. Specifically, a key slot 121 is provided in the cavity of the second mold section 12 along the axial direction of the mold body 1. A key 422 is provided on the outside of the mounting seat 42 to match the key slot 121. The key connection ensures high coaxiality and circumferential positioning between the mounting seat 42 and the second mold section 12.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that not every embodiment contains only one independent technical solution. In the absence of a conflict of solutions, the various technical features mentioned in each embodiment can be combined in any manner to form other implementation methods that can be understood by those skilled in the art.

[0103] In addition, without departing from the scope of the present invention, the technical solutions described in the aforementioned embodiments may be modified, or some of the technical features thereof may be replaced by equivalents, without causing the essence of the corresponding technical solutions to depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A model system for heavy model free flight aerodynamic measurement test, characterized by: The mold body includes a first mold section and a second mold section, wherein the first mold section and the second mold section are connected by a threaded stopper, and a cavity is provided in each of the first mold section and the second mold section; An accelerometer is provided inside the cavity of the first model section; A first mass block, an adjustment mechanism, a second mass block and a model end cover are sequentially provided in the cavity of the second model segment from the direction toward the first model segment to the direction away from the first model segment. The first mass block and the second mass block are both detachably fixed in the cavity of the second model segment. There is a gap between the adjustment mechanism and the first mass block and the second mass block. Two accelerometers are provided in the slide of the adjustment mechanism. The two accelerometers are coaxially arranged, wherein the accelerometer in the cavity close to the first model segment is located at the center of mass of the model system. The position of the slide in the axial direction of the model body can be adjusted by operation. The model end cover is provided at the end of the second model segment. Each of the accelerometers is located on the axis of the model body; The first mass block is provided with a first wire hole passing through the first mass block along the axial direction of the model body; the second mass block is embedded with a data collector; the cable of the accelerometer located in the first model section is connected to the data collector after passing through the first wire hole and the slide cylinder; the cable of the accelerometer located in the second model section is led out from the slide cylinder and connected to the data collector; The first mass block is truncated cone-shaped, and a conical surface matching the first mass block is provided at a corresponding position in the cavity of the second model segment. A first single-layer wave spring is connected to the large end of the first mass block, and the first single-layer wave spring can provide a pre-tightening force on the first mass block. The second mass block is provided with at least one conical section at one end facing the first mass block, and the corresponding position in the cavity of the second model section has a conical surface matching the conical section. A second single-layer wave spring is provided between the model end cover and the second mass block, and the model end cover presses the second single-layer wave spring, thereby providing pre-tightening force for the second mass block.

2. The model system according to claim 1, characterized in that: Positioning grooves are respectively provided on the side walls of the overlapping portion where the first model segment and the second model segment are connected. When the first model segment and the second model segment are connected in place, the two positioning grooves overlap.

3. The model system according to claim 1, characterized in that: A clamping cover is provided at the large end of the first mass block, and a second wire-passing hole coaxial with the first wire-passing hole is provided on the clamping cover. The first single-layer wave spring is arranged between the clamping cover and the first mass block, and the clamping cover is fixed in the cavity of the second model section by a threaded connection. The pre-tightening force of the first single-layer wave spring on the first mass block can be adjusted by rotating the clamping cover.

4. The model system according to claim 3, characterized in that: The end surface of the pressing cover in contact with the first single-layer wave spring is provided with a groove, the first single-layer wave spring is located in the groove, and the side wall of the groove is an inclined surface.

5. The model system according to claim 1, characterized in that: An embedding hole is provided on the second mass block along the axial direction of the model body and passes through the second mass block, and the data collector is installed in the embedding hole; The model end cover is provided with a perspective window sealed with a transparent material for observing the indicator light of the data collector.

6. The model system according to claim 1, characterized in that: An annular groove is provided on the outer peripheral side of one end of the second mass block facing the model end cover, so that a receiving groove is formed between the second mass block and the model end cover. The bottom surface of the receiving groove is an inclined surface, and the second single-layer wave spring is located in the receiving groove.

7. The model system according to claim 6, characterized in that: A copper gasket is provided in the accommodating groove, and the copper gasket is located between the second single-layer wave spring and the second mass block, and is used to adjust the compression gap of the second single-layer wave spring.

8. The model system according to claim 1, characterized in that: The adjustment mechanism further comprises a mounting seat, a thrust bearing, a clamping ring and a support ring, wherein the mounting seat, the thrust bearing, the clamping ring and the support ring are all coaxially arranged with the model body, and the thrust bearing is located between the mounting seat and the clamping ring; The slide is provided with an external thread, and at least two axial sliding planes are provided at intervals along the circumferential direction on the outer side of the slide, so that the external thread is divided into multiple sections in the circumferential direction of the slide. At least one mounting plane is provided inside the slide for mounting the accelerometer. The mounting seat is fixedly mounted in the cavity of the second mold section, and the mounting seat is annular. An axial guide plane matching the axial sliding plane is provided on the inner hole wall of the mounting seat. The slide cylinder is passed through the mounting seat, and the axial sliding plane is arranged in contact with the axial guide plane. The outer circumference and inner side of the clamping ring are both provided with threads, and the clamping ring is connected to the cavity of the second mold section through threads; The outer circumference and inner side of the support ring are both provided with threads. The support ring is arranged on the inner side of the clamping ring and is threadedly connected to the clamping ring. The support ring is sleeved on the outer side of the slide cylinder and is threadedly connected to the slide cylinder.

9. The model system according to claim 8, characterized in that: A keyway is provided in the cavity of the second mold section along the axial direction of the mold body; The outer side of the mounting seat is provided with a key that matches the key slot.

10. The model system according to claim 8, characterized in that: The adjustment mechanism also includes two locking rings; The inner side of the locking ring is provided with an internal thread, and is sleeved on the outer side of the slide and threadedly connected to the slide. The two locking rings are respectively located at the two ends of the mounting seat. The two locking rings are rotated so that the two locking rings are against the two ends of the mounting seat to fix the position of the slide.

Images