64 results about "Specific energy absorption" patented technology

The invention relates to a multi-cell-thin-wall energy absorbing structure and an application structure thereof. The multi-cell-thin-wall energy absorbing structure comprises an outer layer thin-wall energy absorbing structure and an inner layer thin-wall energy absorbing structure. The center line of a hollow small regular prism arranged in the inner layer thin-wall energy absorbing structure in a sleeved mode and the center line of a hollow large regular prism arranged in the inner layer thin-wall energy absorbing structure in a sleeved mode coincide with each other; a first connection rib plate and a second connection rib plate are connected between the middle positions of corresponding edges of the small regular prism and the large regular prism and corresponding corners. Two steel plates of the outer layer thin-wall energy absorbing structure are parallel to two edges of the corresponding edge corner of the inner layer thin-wall energy absorbing structure, and the included angle between the steel plates is the same as the degree number of the corresponding edge corners; one end of a third connection rib plate is connected with the two steel plates, the other end of the third connection rib plate is connected to the outside of the edge of the large regular prism; one end of a fourth connection rib plate is connected to the included angle of the steel plates, and the other end of the fourth rib plate is connected to the outer side of the edge corner of the large regular prism. The multi-cell-thin-wall energy absorbing structure can coordinate the conflict among high specific energy absorption SEA, high crush force efficiency CFE and good deformation modes of the energy absorbing structure, and the overall structure has good collision safety.

The invention discloses a diameter expanding and cutting composite type energy dissipation device and a vehicle with the diameter expanding and cutting composite type energy dissipation device. The energy dissipation device comprises a hollow inner ejector rod, an outer sleeve connected with the other end of the inner ejector rod, an axial positioning rod extending into the inner ejector rod, and an axial positioning sleeve located between the inner ejector rod and the axial positioning rod. The energy dissipation device further comprises a cutting tool fixed to the inner ejector rod. The cutting tool is fixed to the inner ejector rod through an inner gasket and a tool reinforcing bolt. A small notch which can enable the cutting tool to cut the outer sleeve is formed in the position, corresponding to the cutting tool, of the outer sleeve. The energy dissipation device has the advantages of being stable, controllable, high in energy consumption, high in specific energy absorption, relatively simple in structure and manufacturing process, and convenient to install.

The invention discloses a method for testing the buffer performance of a two-dimensional porous material under the high-speed impact condition. The method comprises the steps of carrying out buffer performance testing on the two-dimensional porous material to obtain a corresponding impact force displacement curve, standardizing the impact force displacement curve to obtain a corresponding standardized stress strain curve, and establishing and calculating buffer performance evaluation indexes such as optimal unit volume energy absorption, optimal specific energy absorption, impact force efficiency and a minimal dynamic buffer coefficient, so as to realize the testing of the dynamic buffer performance of the two-dimensional porous material under the high-speed impact load condition. According to the method, the problem that the buffer performance of the two-dimensional porous material under the high-speed impact load condition cannot be researched by virtue of an existing method is solved, samples of different thickness do not need to be tested, an evaluation method is simple, the load condition is similar to an actual impact load and does not influenced by the fluctuation of a curve amplitude value, and the method can be used for researching the influences of factors such as impact speed, structure parameters and unit forms to the buffer performance of the two-dimensional porous material.

The invention discloses a multistage embedded type octagonal automobile energy absorbing and buffering device to solve the problem of an existing automobile energy absorbing and buffering device and designs the energy absorbing and buffering device which is composed of multistage thin-wall energy absorbing cylinders in a embedded and cascaded mode. The multistage embedded type octagonal automobile energy absorbing and buffering device mainly comprises an outer layer thin-wall energy absorbing cylinder (1), an inner layer thin-wall energy absorbing cylinder (2), inter-layer thin-wall energy absorbing cylinder connecting plates (3) and a rear end installation plate (4), wherein both the outer layer thin-wall energy absorbing cylinder (1) and the inner layer thin-wall energy absorbing cylinder (2) of the energy absorbing and buffering device are of an octagonal structure, the inner layer thin-wall energy absorbing cylinder (2) is reduced by a certain length in the axial direction in comparison with the outer layer thin-wall energy absorbing cylinder (1), and therefore stage-by-stage energy absorption can be conducted through multiple layers of energy absorbing cylinders. Meanwhile, all layers of thin-wall energy absorbing cylinders are connected through the four thin-wall energy absorbing cylinder connecting plates (3), and stability in the automobile crashing process is increased. The multistage embedded type octagonal automobile energy absorbing and buffering device has the advantages of being high in specific energy absorption, large in average striking force, small in peak value of the striking force and the like.

The invention relates to a defect-resistant folding mark type energy absorption box, which belongs to a defect-resistant collision energy absorption box for introducing improved folding mark veins into a thin-wall pipe fitting. The improved folding marks can guide the deformation mode of the thin-wall pipe fitting; high defect-resistant capability is also realized. Compared with an ordinary folding mark type thin-wall pipe, the defect-resistant folding mark type energy absorption box has the obvious characteristics that a diamond concave corner in the folding mark type energy absorption box is improved into a double-trapezoidal concave corner, so that the thin-wall pipe fitting capable of effectively resisting the defect can be formed. By introducing the improved folding mark veins, the requirements of high specific energy absorption rate and low peak load are enabled to be realized; meanwhile, the high defect-resistant capability is realized. In addition, the defect-resistant folding mark type energy absorption box has the advantages that the structure is simple, and the manufacturing cost is low.

A method for calculating a local specific energy absorption rate (SAR) on basis of an electric parameter and the mass density of a segmented geometry of an object and a magnetic field vector distribution of a radio frequency (RF) antenna. The values of the electric parameter and the mass density are pre-determined values, while the magnetic field vector distribution is estimated by a magnetic field mapping method based on a magnetic resonance (MR) scan. The magnetic field mapping method based on a magnetic resonance scan can be a Bi mapping method. The invention also relates to a magnetic resonance system by means of which SAR calculation can be done in a relatively short period of time. The invention also relates to a computer program comprising instructions for calculating a local specific energy absorption rate (SAR) according to the above mentioned method. The SAR calculation used in the above mentioned method, system and program is done in the relatively short period of time and as such is practicable in a clinical setting.

The invention discloses a bumper system imitating a bamboo structure. The bumper system is composed of a bumper crossbeam and energy absorption boxes. The bumper crossbeam is composed of a front circular arc face plate, a back circular arc face plate and cover plates. Biomimetic strengthening ribs are welded to the outline of the bumper crossbeam, and the multiple biomimetic strengthening ribs are distributed on the outline of the bumper crossbeam. Each biomimetic energy absorption box is composed of a biomimetic shell, a biomimetic inner tube and constraint rib plates, wherein the biomimetic shell and the biomimetic inner tube are each composed of variable-wall-thickness hexagonal tubes with the same inner diameter and different wall thicknesses, and the wall thicknesses gradually increase from top to bottom; and the six constraint rib plates are distributed uniformly in the circumferential direction and enable the biomimetic shell to be connected with the biomimetic inner tube. The biomimetic strengthening ribs of the bumper crossbeam can strengthen collision properties of vehicles. The energy absorption capacity of the biomimetic energy absorption boxes is increased, and the peak value of collision of the bumper system is reduced while specific energy absorption of the biomimetic energy absorption boxes is improved. Light weight and high efficiency of the bumper system are achieved through the combination of the bumper crossbeam and the biomimetic energy absorption boxes.

The invention provides a multi-cell metal-based carbon fiber composite thin-walled energy absorbing structure and a preparation technique thereof. The energy absorbing structure is mainly in the structural form that inner tubes are wrapped with outer tubes in a nested mode, wherein the structural form is formed by matching and combining the outer tubes constituted by metal tubes or metal-based carbon fiber composite tubes, and the inner tubes constituted by a plurality of carbon fiber tubes or the metal-based carbon fiber composite tubes; the outer walls of the multiple inner tubes are mutually connected in modes of bonding or being supported through metal brackets to form a multi-cell structure; and then the multi-cell structure is connected with the inner walls of the outer tubes throughbonding. The multi-cell metal-based carbon fiber composite thin-walled energy absorbing structure has the advantages of large specific energy absorption, high deformation coordination and guidance, flexible design scheme and the like, the weight of the energy absorbing structure can be decreased, the collision safety of the energy absorbing structure can further be improved, and the targets of safety and light weight of an automobile are effectively achieved. The preparation technique is less in machining step and short in machining time and is suitable for mass production.

The invention discloses a guide combination type special energy absorption structure and application thereon. The structure comprises a front baffle plate (1), a guide rod (2), a thin-wall metal energy absorption structure (4) and a back baffle plate (5); the front baffle plate (1) is fixedly connected with the back baffle plate (5) as a whole through the thin-wall metal energy absorption structure (4); one end of the guide rod (2) is fixedly connected to the front baffle plate (1), and the other end is inserted in the back baffle plate (5) after penetrating through the thin-wall metal energy absorption structure (4); and a groove (41) for penetrating through the guide rod (2) is formed in the outer surface of the thin-wall metal energy absorption structure (4). The special energy absorption structure can be mounted on a front end cross beam of a body chassis structure of a train head, and has such advantages as relatively simple production process, convenience for installation, stable and controllable deformation and high specific energy absorption.

The invention discloses nano ultrahigh-strength concrete with high impact resistance. The nano ultrahigh-strength concrete is characterized by being prepared from the following raw materials: cement,nano particles, silica fume, coal ash, sand, a water reducer and water, wherein the nano particles are one of nano silicon oxide, nano titanium oxide or nano zirconium oxide. The nano particles (comprising nano silicon oxide, nano titanium oxide or nano zirconium oxide) can remarkably strengthen impact toughness and specific energy absorption of ultrahigh-strength concrete. When a strain rate is 280/s to 645/s, nano silicon oxide with high mixing amount can increase the specific energy absorption of the ultrahigh-strength concrete by 159.7%; and when a strain rate is 803/s to 845/s, the specific energy absorption of three nano ultrahigh-strength concrete can be increased to be 200% or above.

The invention belongs to energy absorption accessories of thin-walled tubes in anti-collision structures of vehicles, and particularly relates to a direct-plug type energy absorption assembly of a thin-walled tube. The direct-plug type energy absorption assembly of the thin-walled tube comprises four energy absorption elements and fixing elements. Each energy absorption element is a multilayer composite round tube, and tube wall materials of adjacent layers of each multilayer composite round tube are mutually orthogonal. The two ends of each energy absorption element are fixed to the fixing elements, the other side of each fixing element is provided with a petal-shaped opening, and the energy absorption elements and the fixing elements are mounted in the thin-walled tube. Through the direct-plug type energy absorption assembly of the thin-walled tube, the bearing capacity and the specific energy absorption rate of unit mass of the thin-walled tube are increased, a load uniformity coefficient is reduced, local buckling and damage are reduced, and plastic deformation is evenly distributed on more sections. Meanwhile, the direct-plug type energy absorption assembly of the thin-walled tube is stable, reliable and capable of coping with normal loads of different portions and directions, and external shock kinetic energy can be irreversibly dissipated through plastic deformation in a stable damage mode and in an adjustable way.

The invention belongs to the field of energy absorbing in passive structural safety protection, and discloses a fabricated self-locking multi-cell energy absorber. The fabricated self-locking multi-cell energy absorber comprises two sets of thin-wall pipes, and the structural sizes of the thin-wall pipes in each set are the same; openings are formed in the side faces of all the thin-wall pipes, and thus the thin-wall pipes are each of a non-closed structure; the two open thin-wall pipes in the first set are parallelly arranged, and the openings of the two open thin-wall pipes in the first setare opposite; the two thin-wall pipes in the second set are parallelly arranged, and the openings of the two open thin-wall pipes in the second set are back on to each other; the second set is nestedin the first set orthogonally, four empty cells are formed, and meanwhile each face of the energy absorber is made to comprise two layers of pipe walls of the corresponding thin-wall pipe; and the second set and the first set mutually penetrate through the openings of each other to achieve splicing of the two sets to form a self-locking structure, and each face of the structure comprises the two corresponding layers of pipe walls. Through the fabricated self-locking multi-cell energy absorber, the provided energy absorber is simple in structure, high in specific energy absorption rate and lowin production cost.

The invention discloses a bionic energy absorption pipe of a bamboo-like structure, comprising a cylindrical outer pipe, a plurality of restraining rings, a plurality of restraining walls and a plurality of restraining beams, wherein the plurality of restraining rings are equidistantly arranged on the cylindrical outer pipe, each restraining wall is cylindrical, the plurality of restraining walls are sleeved in the cylindrical outer pipe, the plurality of restraining beams are arranged between the cylindrical outer pipe and the restraining walls and between the adjacent restraining walls, each restraining beam is connected with the adjacent two restraining walls through two supporting plates, and the restraining beams are in shapes of circular tubes; and the distribution density rho of the restraining beams is equal to n/2paiR, the rho represents the density of the restraining beams, the n represents the number of each layer of the restraining beams, and the R represents the radius of a circle in which the centers of the restraining beam are located. The bionic energy absorption pipe disclosed by the invention improves the capability of axially absorbing energy, namely improving the SEA (specific energy absorption), and also improving the transverse bearing capability.

The invention discloses a carbon fiber honeycomb tube structure, and relates to the field of protective structures. A traditional protective structure is high in weight and simplex in material and structure form. A carbon fiber honeycomb tube is prepared from pultrusion tubes with orthogonal carbon fibers being laid, and the large tubes and the small tubes are connected into a whole through resin.The carbon fiber tube structure obtained through a pultrusion process has the advantages of large strength, high stiffness, fast forming and the like, and is lower in weight, larger in stiffness andhigher in specific energy absorption compared with the traditional protective structure; and the needed forms can be prepared according to the demands, and the application range is wide.

The invention discloses a circular tube type laser welded sandwich plate explosion-proof wall. The circular tube type laser welded sandwich plate explosion-proof wall comprises a sandwich plate explosion-proof wall body and a supporting structure body, and the sandwich plate explosion-proof wall body is mounted on a module truss of the upper of a target platform through the supporting structure body; the sandwich plate explosion-proof wall body comprises a first panel, a second panel and a sandwich layer, and the sandwich layer is formed by a plurality of circular tube which are arranged vertically and paralelly; the first panel and the second panel are correspondingly arranged on the two sides of the sandwich layer, the first panel serves as an explosion facing face, and the second panelserves as an explosion backing face; and the first panel and the second panel are correspondingly connected with each circular tube in the sandwich layer in a laser welded mode. The sandwich layer ofthe explosion-proof wall body has the characteristics of being high in specific energy absorption, low in first peak crumpled load and long in crumpled stroke so that the explosion-proof wall body canabsorb impact energy well; and meanwhile, the first panel and the second panel are arranged on the two sides of the sandwich layer, so that the explosion-proof wall body has the characteristics of being large in in-plane bending rigidity and high in specific strength, and the explosion-proof capability of the explosion-proof wall body can be further improved.

The invention discloses an adjustable circular tube energy absorption/energy storage mechanism based on paper-cut structures, and belongs to the technical field of advanced intelligent structures. According to the structure, local cutting is carried out on traditional circular tubes, the notch direction is in the axial direction of the circular tubes, and the plurality of circular tubes are arrayed in a specific mode according to actual application requirements. When the circular tubes are subjected to axial impact force, cutting sections of the circular tubes deform in the specific direction, structural energy absorption and energy storage are achieved through local buckling deformation, after external force is removed, deformation recovers, and the stored energy is released. According to the structure, the paper-cut structures are introduced into local areas of the circular tubes, the structure has the characteristics of high specific energy absorption rate and low peak load by adjusting the characteristic parameters of notches, and the structure can recover to original deformation after the axial impact load disappears, so that the structure can be reused. The adjustable paper-cut circular tubes have the advantages of being easy to process, low in manufacturing cost, easy to replace and the like, and are expected to be applied to collision energy absorption and energy storage parts of large devices such as traffic equipment and aerospace.

The invention provides a thin-walled energy-absorbing device when a vehicle is passively collided and belongs to the technical field of damping parts for vehicle collision impact. The energy-absorbing device comprises energy-absorbing units which are connected with one another and have the same structure and size; the inner surface of each energy-absorbing unit is in a regularly N-sided shape, and each side of the energy-absorbing unit forms an energy-absorbing body of the energy-absorbing unit; and the outer surface of the energy-absorbing body is of a pyramid-shaped corrugated structure. When the energy-absorbing device is a regularly 11-sided thin-walled cylinder, the height h of each energy-absorbing unit is 70.38 mm; when the radius of an externally tangent circle on the inner surface of each energy-absorbing unit is 40.16 mm, the energy-absorbing effect of the energy-absorbing device is optimal. The energy-absorbing device has the benefits that the requirements of high specific energy absorption ratio and low load uniformity coefficient can be simultaneously satisfied, and the performances of deformation controllability and impact adsorption function when a thin-walled energy-absorbing structure is widely applied to a vehicle is passively collided are improved, so that the passive safety of the vehicle is improved.

The invention belongs to the technical field of automobile safety protection, and particularly discloses an automobile collision energy absorption composite material and a preparation method thereof.The composite material comprises M layers of particle reinforced foamed aluminum core materials and M+1 layers of dual-phase steel plates, the foamed aluminum core materials and the dual-phase steel plates are sequentially and alternately stacked, and the dual-phase steel plates are composed of austenite phases and martensite phases. According to the automobile collision energy-absorbing material,martensite is induced to form through dual-phase steel deformation at the moment of collision, so that a large amount of energy is absorbed at the moment of collision, the structure is kept stable, then residual energy is absorbed through porous fluffy foamed aluminum, and the defects that a traditional collision energy-absorbing structure is prone to losing efficacy at the moment of collision, and the energy absorption effect cannot be completely reflected are overcome. Besides, the dual-phase steel has higher strength and work hardening rate than aluminum alloy and other light metals, so that higher specific energy absorption can be realized under the condition of not sacrificing the strength and light weight, the same safety goal is achieved, and meanwhile, more cost is saved.

The invention provides a high-specific energy absorption lattice configuration under a low-density condition. The lattice configuration comprises a support plate consisting of an upper panel and a lower panel, and a dot matrix core material installed between the upper panel and the lower panel and comprising two X-shaped rod pieces with a same structure; and each X-shaped rod piece comprises two orthogonally connected inclined rods and supporting rods located in the opening ends of the two sides of a connecting point respectively, two ends of each inclined rod form fixing ends making contact with the upper panel and the lower panel, and the two X-shaped rod pieces are orthogonally clamped through a connecting point of the two inclined rods. Under the action of an out-of-plane compression load, the lattice rod pieces keep an in-plane deformation mode, the density of the rod pieces at the center node is gradually increased, the bearing capacity of the lattice structure after peak is further improved through the friction and extrusion action between the rod pieces, rapid reduction of the bearing capacity caused by deformation of the rod pieces in the compression process is avoided, and kinetic energy caused by impact can be stably absorbed by a relatively high platform load.

The invention discloses a multi-cell energy absorption structure combination optimization design method, which comprises the following steps: establishing a multi-cell energy absorption structure finite element model according to a material to be optimized, and determining a design variable, a constraint condition and an optimization target; carrying out an orthogonal experiment according to the established three-level design variable table of the variables and an optimization target; establishing a target response data matrix, and performing Taguchi analysis on the target response data matrix; performing grey correlation analysis based on the normalized signal-to-noise ratio sequence of each response to obtain a grey correlation coefficient sequence corresponding to each response; determining a preliminarily optimized variable combination to realize rapid positioning of a preliminarily optimized result in a large space; selecting a significant influence variable and carrying out secondary optimization by using a preliminary optimization variable; and carrying out multi-objective continuous optimization design to obtain a Pareto leading edge of an optimization problem, and determining an optimal compromise design point. According to the method, the specific energy absorption of the structure can be improved, the peak acceleration can be reduced, and the lightweight and safety performance of the structure can be improved to a great extent.

The invention discloses an energy absorbing box provided with a concave polygonal section and provided with a fold at one end and belongs to the field of vehicle structures including automobiles, trains and the like. According to the purpose, kinetic energy is absorbed through stress deformation of the structure during colliding. The energy absorbing box is characterized in that the concave polygon serves as the section, the fold is introduced to one end of the structure, and therefore the novel energy absorbing box is formed. The energy absorbing box has the beneficial effects that due to thefact that the concave polygonal section is used, more edges and corners are introduced into the structure, the energy absorbing potential on the structural theory is improved, meanwhile, the fold isled to one end of the structure, and therefore the structure can be led to generate a designed stable and gradual deformation manner during stress, and the ultrahigh specific energy absorption rate (increased by 100% to 200% than that of a traditional energy absorbing box) is achieved. Due to introduction of the fold, the structural rigidity is lowered, and the energy absorption box can have the low-load uniformity coefficient at the same time. By means of the energy absorbing box, the fold shape is convenient to form, the surface of the whole structure is a developable surface, the whole structure can be machined and formed directly through a piece (or multiple pieces) of thin flat plates, and therefore machining can be more convenient and more accurately.