CN211553486U

CN211553486U - Fatigue test piece for airplane stringer wallboard

Info

Publication number: CN211553486U
Application number: CN201922419495.2U
Authority: CN
Inventors: 纪露明; 游新梅; 史志俊; 张彦军
Original assignee: Xian Aircraft Design and Research Institute of AVIC
Current assignee: Xian Aircraft Design and Research Institute of AVIC
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-09-22
Anticipated expiration: 2029-12-27

Abstract

The utility model provides an aircraft stringer wallboard fatigue test spare, contains covering, stringer, architrave, stringer joint, the testpieces covering be the rectangle, is equipped with the stringer at the longitudinal center of covering, the one end and the architrave of covering are connected, the stringer passes through the stringer joint on the covering and is connected with the architrave, the other end of stringer is the bevel transition structure, the other end and the wedge backing plate stromatolite of covering are connected, the wedge end of this wedge backing plate is located between the bevel transition structure of covering and stringer.

Description

Fatigue test piece for airplane stringer wallboard

Technical Field

The utility model belongs to an aircraft structural strength test field relates to a stringer, wallboard and frame or rib connection structure's fatigue test spare design among the aircraft structural strength test field.

Background

In the aircraft structural strength test, need be connected or wing rib and stringer, wallboard connection structure to fuselage frame and stringer, covering carry out experimental planning design, wherein key core has two points: 1. the problem of how to evenly transmit the load of the loading section to the stringer and the wallboard is solved, and the stress of the stringer and the wallboard in the equal straight section is ensured to be consistent; 2. the connection area of the stringer joints, panels and frames or ribs is ensured to be the weakest part of the overall test piece.

The fatigue test piece of the connection structure of the stringer, the skin and the fuselage frame or the connection structure of the stringer, the wallboard and the wing rib in the prior art often has the following phenomena: 1) the load of the loading section is directly transferred from the wall plate, and the stringer basically does not transfer the load; 2) the centroid of the loading section is inconsistent with that of the long-purlin wallboard of the test section, and the test piece is locally bent; 3) test damage does not occur in the assessment area; all three of these conditions can cause the test to fail. Therefore, how to design the transition section of the stringer wallboard test piece to enable the stress of the stringer and the skin at the equal straight section of the test piece to be consistent in the loading direction, and the test piece damage to be generated in the assessment area is the key point for solving the problem.

Disclosure of Invention

The application aims to solve the problems existing in the prior art and provides a fatigue test piece for a stringer wallboard of an airplane

The utility model provides an aircraft stringer wallboard fatigue test spare, contains covering, stringer, architrave, stringer joint, its characterized in that, the testpieces covering be the rectangle, be equipped with the stringer at the longitudinal center of covering, the one end and the architrave of covering are connected, the stringer passes through the stringer joint on the covering and is connected with the architrave, the other end of stringer is the bevel transition structure, the other end and the wedge backing plate stromatolite of covering are connected, the wedge end of this wedge backing plate is located between the bevel transition structure of covering and stringer.

The beneficial effect of this application lies in: 1) firstly, arranging a wedge-shaped base plate on a test clamping section of a wallboard to ensure that the centroid of the test clamping section is consistent with the combined centroid of the stringer wallboards at the test equal straight section; 2) and secondly, the stringer is in bevel transition at the wedge-shaped base plate inclined table, so that the load of the test loading end can be uniformly transmitted to the wallboard stringer, the fatigue failure is caused in a stringer joint examination area, and the test result is reliable and effective.

The present application is described in further detail below with reference to the accompanying drawings of embodiments:

drawings

FIG. 1 is a schematic view of a stringer panel fatigue test piece of the present application

FIG. 2 is a schematic view of the frame structure of FIG. 1

FIG. 3 is a schematic view of the wall structure of FIG. 1

FIG. 4 is a schematic view of the wedge-shaped pad of FIG. 1

FIG. 5 is a schematic illustration of the stringer joint configuration of FIG. 1

FIG. 6 is a schematic view of the stringer configuration of FIG. 1.

The numbering in the figures illustrates: 1 frame edge, 2 covering, 3 wedge-shaped base plates, 4 stringer joints, 5 stringers and 6 tapered transition structures.

Detailed Description

Referring to the attached drawings, the application provides an aircraft stringer wallboard fatigue test piece, which comprises a skin 2, a stringer 5, a frame edge 1 and a stringer joint 4 and is characterized in that the test piece simulates a wallboard structure of an aircraft, the skin 2 is rectangular, the stringer 5 is arranged at the longitudinal center of the skin 2, one end of the skin 2 is connected with the frame edge 1, the stringer 5 on the skin 2 is connected with the frame edge 1 through the stringer joint 4, the other end of the stringer 5 is a tapered transition structure 6, the other end of the skin 2 is connected with a wedge-shaped base plate 3 in a laminated mode, and the wedge-shaped end of the wedge-shaped base plate 3 is located between the skin 2 and the tapered transition structure 6 of the stringer.

The wedge-shaped base plate 3 is arranged on the test clamping section of the test piece, so that the centroid of the test clamping section is consistent with the combined centroid of the stringer wallboard at the test equal straight section; the wedge-shaped base plate 3 is in a structure form of a bevel transition frustum, the transition gradient is 3 degrees, the sharp edge of the wedge-shaped base plate is properly chamfered, and the wedge-shaped base plate 3 is connected with the skin 2 through a large number of rivets; the stringer 5 is tapered at the tapered platform of the wedge-shaped base plate 3 and transits to the tail end, in the embodiment, the taper angle of the stringer stud is 10.39 degrees, the taper angle of the short side of the upper part of the stringer is 4.71 degrees, and the stringer 5 is connected with the wedge-shaped base plate 3 and the skin 2 through rivets.

Take an aircraft stringer panel test piece design as an example:

fig. 1 shows a schematic view of the test piece, including the rim 1, the wall panel 2, the wedge plate 3, the stringer tape 4 and the stringer 5. If the fatigue test piece is designed according to the prior art, the load of the test loading end can be directly transmitted through the skin, the stringer hardly transmits the load, the test loading condition of the test checking section (the stringer, the wallboard, the stringer joint and the frame edge butt joint area) is inconsistent with the actual structure loading condition of the airplane, and the test result is unreliable. According to the utility model discloses a test piece adopts wedge backing plate 3 and takes the stringer of bevel transition structure 6, and the load of experimental loading end evenly transmits covering 2 and stringer 5 through the bevel transition structure 6 of wedge backing plate 3 and stringer 5 on, and straight section covering and stringer are unanimous at the stress size of loading direction such as test in testing to identical with finite element analysis result, the test result is true credible, has proved the utility model discloses a feasibility.

In practice, the stringer preferably has a chamfered transition angle at the vertical edge of no greater than 15 degrees. In FIG. 5, the stringer vertical rib bevel angle is 10.39 degrees, the stringer upper short edge bevel angle is 4.71 degrees, and the stringer is connected with the wedge-shaped backing plate and the skin through rivets.

Preferably, the stringer has a chamfered vertical edge length of approximately one third of the stringer length.

Preferably, wedge backing plate 3 contains wedge end and straight end, and straight end is one and is connected with the covering end with the equal thickness rectangle of covering 2's end matching, and the wedge end is the trapezium structure of a variable thickness, and its thickness variation angle is for being not more than 3 degrees, and the front end of wedge end is the minor face and the thinner edge of trapezium structure, and the rear end of wedge end is the long limit and the thicker edge of trapezium structure, and the front end width of wedge end corresponds with the base of long purlin, and the rear end and the straight end weight of wedge end are as an organic whole.

The preferred stringer 5 is a Z-section, with the tapered transition at the end of the stringer including a chamfered transition at the vertical edge and a chamfered transition at the top edge, with the chamfered transition at the vertical edge being no greater than 15 degrees and the chamfered transition at the top edge being no greater than 5 degrees.

It is noted that while the above description illustrates and describes several preferred embodiments of the invention, as noted above, it is to be understood that the invention is not limited to the forms disclosed herein, but is not intended to be exhaustive of other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept as expressed above, or as determined by the skilled artisan in the relevant art. But that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention, which is to be limited only by the claims appended hereto.

Claims

1. The utility model provides an aircraft stringer wallboard fatigue test spare, contains covering, stringer, architrave, stringer joint, its characterized in that, the testpieces covering be the rectangle, be equipped with the stringer at the longitudinal center of covering, the one end and the architrave of covering are connected, the stringer passes through the stringer joint on the covering and is connected with the architrave, the other end of stringer is the bevel transition structure, the other end and the wedge backing plate stromatolite of covering are connected, the wedge end of this wedge backing plate is located between the bevel transition structure of covering and stringer.

2. An aircraft stringer web fatigue test article according to claim 1, wherein said stringer has a chamfered vertical edge transition angle of not more than 15 degrees.

3. An aircraft stringer web fatigue test article according to claim 1 or 2, wherein said stringer has a chamfered vertical edge length of approximately one third of the stringer length.

4. The fatigue test piece of an aircraft stringer web according to claim 1 or 2, wherein the wedge-shaped backing plate has a wedge-shaped end and a flat end, the flat end is a rectangle of equal thickness matching the end of the skin and connected to the end of the skin, the wedge-shaped end is a trapezoidal structure of variable thickness having a thickness variation angle of not more than 3 degrees, the front end of the wedge-shaped end is a short side and a thinner side of the trapezoidal structure, the rear end of the wedge-shaped end is a long side and a thicker side of the trapezoidal structure, the width of the front end of the wedge-shaped end corresponds to the bottom edge of the stringer, and the rear end of the wedge-shaped end and the flat end are integrated.

5. An aircraft stringer web fatigue test article according to claim 1, wherein said stringer is of Z-section and terminates in a tapered transition structure comprising a chamfered vertical edge transition and a chamfered top edge transition, said chamfered vertical edge transition having an angle of not greater than 15 degrees and said chamfered top edge transition having an angle of not greater than 5 degrees.