CN115447629B - Multi-pipe combined energy absorbing device with different heights and ripple phases - Google Patents

Abstract

The invention discloses a multi-tube combined energy absorbing device with different heights and ripple phases, which comprises a thin-wall shell with an inner cavity, a plurality of energy absorbing corrugated tubes arranged in the inner cavity, and a front end plate for sealing the inner cavity, wherein each energy absorbing corrugated tube has different heights, and the ripple curve of the side wall of each energy absorbing corrugated tube meets the following conditionsWherein i is the serial number of the energy absorbing corrugated pipe; the side wall of each energy-absorbing corrugated pipe is provided with a wave crest and a wave trough, and the wave crests and the wave troughs between two adjacent energy-absorbing corrugated pipes are arranged in a staggered manner; the initial peak load originally concentrated is separated by introducing the height difference configuration characteristic to enable the energy-absorbing corrugated pipes to be misplaced during initial deformation, so that the initial peak load of the whole device can be greatly reduced; the introduction of the corrugated phase difference configuration features changes the positions of the peaks and the troughs of the side wall sinusoidal curves, so that different pipe fittings compensate each other during deformation, and the subsequent load peaks of each pipe are fully separated, thereby obviously reducing the subsequent load fluctuation of the combined structure.

Description

A multi-tube combined energy absorbing device with different heights and corrugation phases

Technical Field

The invention relates to the field of vehicle collision safety, and in particular to a multi-tube combined energy absorbing device with different heights and corrugation phases.

Background Art

As the speed of high-speed railways continues to increase, the requirements for train safety are also getting higher and higher. Train collisions are very serious accidents. The energy absorption protection device installed on the train can protect people's lives and property safety at the first time. The thin-walled circular tube structure can absorb a large amount of energy when it is impacted, thereby absorbing the impact caused by the collision. Although simply stacking the number of pipes can multiply the energy absorption of the energy absorption protection device, there are also some problems, such as excessive initial load peak and load fluctuations, etc. These problems may not be able to protect people's lives and property safety well in the event of an accident, causing unnecessary losses.

Summary of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a multi-tube combined energy absorbing device with high energy dissipation, low initial peak value, small load fluctuation and different heights and corrugation phases.

In order to solve the above technical problems, the present invention adopts the following technical solutions: a multi-tube combined energy absorbing device with different heights and corrugation phases, comprising a thin-walled shell with an inner cavity, a plurality of energy absorbing bellows placed in the inner cavity, and a front end plate covering the inner cavity, wherein each of the energy absorbing bellows has a different height;

The corrugation curve of the side wall of each energy-absorbing bellows satisfies Wherein, i is the serial number of the energy absorbing bellows; the side wall of the energy absorbing bellows is formed with crests and troughs, and the crests and troughs between two adjacent energy absorbing bellows are staggered.

As a further improvement of the above technical solution:

The plurality of energy absorbing bellows are arranged in the inner cavity at equal distances from high to low or from low to high.

A plurality of the corrugated energy absorbing tubes are arranged in a plurality of rows in the inner cavity.

The energy absorbing bellows is fixed in the inner cavity by welding.

The bottom diameter of the energy absorbing bellows is 40 mm and the wall thickness is 2 mm.

Compared with the prior art, the advantages of the present invention are:

The present invention provides a multi-tube combined energy absorbing device with different heights and corrugation phases. By introducing a height difference configuration feature, multiple energy absorbing bellows are displaced during initial deformation, and the initial peak loads of each energy absorbing bellows are controlled to be compactly distributed at different time nodes, so that the originally concentrated initial peak loads are separated, and the initial peak load of the entire device can be greatly reduced; the introduction of the corrugation phase difference configuration feature changes the positions of the peaks and troughs of the side wall sinusoidal curve, and the positions of the peaks and troughs determine the time nodes of the wrinkle deformation, and the time nodes of the wrinkle deformation determine the time nodes of the subsequent peak loads. By giving each pipe component corrugation a suitable different phase, the entire device can have wrinkles deforming at all times during the deformation process, so that different pipe components compensate each other during deformation, and the subsequent load peaks of each pipe are fully separated, thereby significantly reducing the subsequent load fluctuations of the combined structure, so that the multi-tube combined energy absorbing device has a smooth impact force curve like a honeycomb structure, thereby achieving perfect compatibility of excellent energy absorption characteristics such as high energy dissipation, low initial peak, and small load fluctuation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of the three-dimensional structure of the multi-tube combined energy absorbing device of the present invention.

FIG. 2 is a schematic diagram of the three-dimensional structure of the arrangement of six energy-absorbing bellows of the present invention.

FIG3 is a schematic diagram of the three-dimensional structure of a typical uniformly distributed bellows (a single energy-absorbing bellows or multiple energy-absorbing bellows of the same height).

FIG. 4 is a schematic diagram of the arrangement structure of multiple energy-absorbing bellows of different heights according to the present invention.

FIG5 is a schematic diagram of a typical bellows compression stage (the relationship between wave peak value, wave trough value and wrinkle formation).

FIG. 6 is a diagram showing the expected effect of the multi-tube combined energy absorbing device combining height difference and phase difference when subjected to force.

FIG. 7 is a schematic diagram of the load-displacement of each pipe when only the height difference configuration is introduced.

FIG8 is a schematic diagram of the load-displacement of each pipe fitting when only the corrugation curve phase difference configuration is introduced.

FIG9 is a schematic diagram of the load-displacement of each pipe fitting when the height difference and the corrugation phase difference are introduced simultaneously.

FIG. 10 is a schematic diagram showing a comparison between the results of the six-tube combined energy absorbing device of different configurations of the present invention and the traditional six-tube combined energy absorbing device of the same configuration.

FIG. 11 is a schematic diagram comparing the impact force performance of the six-tube energy absorbing device of different configurations of the present invention and the traditional six-tube energy absorbing device of the same configuration.

The symbols in the figure represent:

1. Front end plate; 2. Energy absorbing bellows; 3. Thin-walled shell; 31. Inner cavity; A ₁ -A ₆ , six energy absorbing bellows.

DETAILED DESCRIPTION

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

Figures 1 to 11 show an embodiment of a multi-tube combined energy absorbing device with different heights and corrugation phases of the present invention, including a thin-walled shell 3 with an inner cavity 31, a plurality of energy absorbing bellows 2 placed in the inner cavity 31, and a front end plate 1 covering the inner cavity 31, wherein the plurality of energy absorbing bellows 2 have different heights; the corrugation curve of the side wall of each energy absorbing bellows 2 satisfies Wherein i is the serial number of the energy absorbing bellows 2; the side wall of the energy absorbing bellows 2 is formed with crests and troughs, and the crests and troughs between two adjacent energy absorbing bellows 2 are staggered.

The multi-tube combined energy-absorbing device introduces a height difference configuration feature to cause multiple energy-absorbing bellows 2 to be misaligned during initial deformation, controls the initial peak loads of each energy-absorbing bellows 2 to be compactly distributed at different time nodes, separates the originally concentrated initial peak loads, and significantly reduces the initial peak load of the entire device; the introduction of the corrugation phase difference configuration feature changes the positions of the peaks and troughs of the side wall sinusoidal curve, and the positions of the peaks and troughs determine the time nodes of wrinkle deformation, which in turn determine the time nodes of subsequent peak loads. By giving each pipe corrugation a suitable different phase, the entire device can have wrinkles deforming at all times during the deformation process, so that different pipes compensate each other during deformation, and the subsequent load peaks of each pipe are fully separated, thereby significantly reducing the subsequent load fluctuations of the combined structure, so that the multi-tube combined energy-absorbing device has a smooth impact force curve like a honeycomb structure, thereby achieving perfect compatibility of excellent energy absorption characteristics such as high energy dissipation, low initial peak, and small load fluctuations (as shown in Figure 6).

In this embodiment, taking six energy absorbing bellows 2 (A ₁ -A ₆ ) as an example, the six energy absorbing bellows are arranged in two rows at an appropriate distance and equidistantly in the inner cavity 31 . The structural parameters of the six energy absorbing bellows 2 are shown in Table 1 below:

Table 1

_Hi is the height of each pipe fitting, ΔH is the height difference between the pipe fittings, the diameter D of the bottom circle of each pipe fitting is 40 mm, and the wall thickness T is 2 mm.

In this embodiment, the energy absorbing bellows 2 is fixed in the inner cavity 31 by welding.

The energy-absorbing bellows 2 selected in this embodiment has a weak structure at the positions of the peaks and troughs of the sinusoidal curve of its side wall, which can be used as a deformation inducing structure. Therefore, the timing of the deformation of the pipe fitting can be controlled by controlling the positions of the peaks and troughs on the pipe fitting, as shown in Figure 6, that is, each tube is given a suitable height and corrugation phase. Since the pipe fittings have different configuration characteristics, the deformation initiation and duration of the folds of each pipe fitting are different during the compression process. Therefore, a certain timing difference will be generated between the load-displacement curves of each pipe fitting, that is, the peak load of each pipe will be fully separated.

As shown in Figure 5, it is a typical bellows compression stage diagram. The peak load on the load-displacement curve is closely related to the wrinkle forming process. Each deformed wrinkle means that the load curve will have corresponding peak values and trough values. Since the configuration characteristics of the energy-absorbing bellows 2 are directly related to the deformation process of the wrinkles, giving the energy-absorbing bellows 2 appropriate configuration characteristics can obviously achieve the purpose of controlling the peak load formation sequence of the energy-absorbing pipe according to actual needs. The existing research on multi-tube combined energy-absorbing devices is mainly based on the same configuration. In the combined energy absorption process, the load curves of each energy-absorbing bellows 2 will completely overlap. Although the energy dissipation capacity of the overall device is significantly improved after direct combined application, the initial peak value and subsequent load fluctuations of the combined structure will also increase significantly with the number of pipes, which is obviously not conducive to the smooth dissipation of impact kinetic energy.

Figure 7 shows the load-displacement diagram of each pipe when only the height difference configuration is introduced. It can be found that although a certain time sequence difference is formed between the initial peak loads of each pipe, there is still an obvious overlap in the subsequent peak loads of each pipe, and it is obviously impossible to achieve the goal of small load fluctuations.

Figure 8 shows the load-displacement diagram of each pipe when only the corrugation curve phase difference configuration is introduced. It can be found that although the subsequent peak loads of each pipe are effectively separated, the initial peak loads of each pipe completely overlap, which obviously makes it difficult to achieve the goal of a small initial peak load.

Figure 9 shows the load-displacement diagram of each pipe when the height difference and corrugation phase difference are introduced at the same time. It can be found that all peak loads of each pipe are fully separated, which can minimize the subsequent load fluctuation of the composite structure while maintaining a small initial load peak.

FIG10 shows the comparison between the results of the six-tube combined energy absorbing device of different configurations of the present invention and the traditional six-tube combined energy absorbing device of the same configuration. It can be found that the initial peak load and load fluctuation are significantly reduced without substantially reducing the energy absorption of the device, which is obviously more conducive to protecting the safety of the occupants.

Figure 11: The impact force performance comparison between the traditional six-tube energy absorbing device of the same configuration and the six-tube energy absorbing device of different configurations of the present invention is shown with specific data, where _P1 is the initial peak load, _Ed is the energy absorption, SEA is the specific energy absorption, Fm is the average load, and FLU _0-100 is the load fluctuation. Through the specific data comparison, it can be found that the six-tube energy absorbing device of different configurations of the present invention is compared with the traditional six-tube energy absorbing device of the same configuration. When the energy absorption _Ed is only reduced by 5.43% and the specific energy absorption SEA is only reduced by 3.72%, the initial peak load _P1 is reduced by 28.76%, and the load fluctuation FLU _0-100 is reduced by 65.74%.

In this embodiment, only the working condition of combining six energy-absorbing bellows 2 with different configurations for energy absorption is proposed. Of course, the number of pipes i, the initial height H ₀ of the pipes, the height difference ΔH, the amplitude A of the corrugation curve, the phase The structural parameters such as frequency a are used to adapt to various complex application scenarios, so as to achieve the design goal of minimizing the initial peak load of the combined structure and subsequent load fluctuations while meeting the energy dissipation capacity.

Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present invention by using the technical contents disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims (2)

1. A multi-tube combined energy absorbing device with different heights and corrugation phases, characterized in that it comprises a thin-walled shell (3) with an inner cavity (31), a plurality of energy absorbing bellows (2) disposed in the inner cavity (31), and a front end plate (1) covering the inner cavity (31), wherein each of the energy absorbing bellows (2) has a different height; The corrugation curve of the side wall of each energy absorbing bellows (2) satisfies y=sin(0.3x+φ _i ), wherein i is the serial number of the energy absorbing bellows (2); the side wall of the energy absorbing bellows (2) is formed with crests and troughs, and the crests and troughs between two adjacent energy absorbing bellows (2) are arranged in a staggered manner; A plurality of the energy absorbing bellows (2) are arranged in an equidistant manner from high to low or from low to high in the inner cavity (31); A plurality of the energy absorbing bellows (2) are arranged in a plurality of rows in the inner cavity (31); The energy absorbing bellows (2) is fixed in the inner cavity (31) by welding. 2. A multi-tube combined energy absorbing device with different heights and corrugation phases according to claim 1, characterized in that the bottom diameter of the energy absorbing bellows (2) is 40 mm and the wall thickness is 2 mm.