CN108894348B

CN108894348B - Modularized pneumatic resistance reducing device based on bionics and high-rise building

Info

Publication number: CN108894348B
Application number: CN201810781114.2A
Authority: CN
Inventors: 赵林; 丁叶君; 崔巍; 葛耀君
Original assignee: Tongji University
Current assignee: Tongji University
Priority date: 2018-07-16
Filing date: 2018-07-16
Publication date: 2020-05-08
Anticipated expiration: 2038-07-16
Also published as: CN108894348A

Abstract

The invention discloses a bionic-based modular pneumatic resistance reducing device and a high-rise building. Each blade can independently deform and vibrate, the aerodynamic appearance can be adaptively changed under the action of different winds, the wind resistance is reduced under various conditions, the blades are allowed to vibrate, the energy can be consumed while the resistance is reduced, and the wind-induced vibration of a high-rise building is further reduced.

Description

Modularized pneumatic resistance reducing device based on bionics and high-rise building

Technical Field

The invention relates to the technical field of buildings, in particular to a modular pneumatic damping device applied to buildings.

Background

In the last hundred years, the world record of building height has been refreshed frequently, the use function is removed, and high-rise buildings or also become symbolic signs of industrial civilization and the landmark of modernized cities, so that more and more high-rise buildings are designed and built. Wind-induced static and dynamic response of a building structure is also important and hard to control.

The natural wind in the atmospheric boundary layer has pulsating wind components, the pulsating wind can be considered to be formed by random combination of vortices with different scales, and because the natural frequency of the building structure is generally higher and far away from the frequency of the vortices with the super-large scale, the vortices with the large scale cannot cause the resonance response of the building, but the vortices with the small scale and higher probability are likely to generate the resonance response due to the higher frequency and the similarity with the fundamental frequency of the building. The downwind structural response of the building is mainly buffeting response generated under the action of dynamic wind load, most buildings can generate torsional vibration besides downwind vibration, and the torsional structural response is always coupled with the downwind structural response.

When an airflow passes through a building, the wake generated in the leeward region of the building appears to be periodic to varying degrees, from periodic with a single frequency to completely turbulent, due to flow separation, vortex formation and fragmentation, and the turbulent nature of the airflow. At any determined moment, the wake is asymmetric, and the wake induces large-amplitude cross-wind vibration on the building.

When air current crosses a building with a circular section or a square section, vortex is generated at the tail part, if the vortex falls off from two sides of the building alternately, karman vortex street is generated, and alternating periodic exciting force acts on the building at the moment to cause periodic vibration of the structure, namely vortex-induced vibration. If the vortex shedding frequency is close to the natural frequency of the building, the structure will vibrate in a larger amplitude, which may cause discomfort for people in the high-rise building.

Galloping may also be caused when a high velocity airflow passes through a building of non-circular cross-section. This is a divergent self-excited vibration having a vibration frequency close to the natural frequency of the building, which if not avoided, can lead to structural damage.

At present, the structural response control of high-rise buildings under the action of wind mainly comprises the following modes:

(1) and (5) correcting the pneumatic appearance. The vortex synchronism can be broken by correcting the geometric structure of the cross section layer to reduce the resistance or change the vortex separation point, and the vortex synchronism can be broken by correcting the longitudinal section (in the height direction of a high-rise building), so that the vortex shedding load is reduced.

(2) An inertial damper is provided. The building frequency response is modified by the inertial damping through dynamic interaction between the building and the damper mass to provide additional damping to the building. Inertial dampers include tuned mass dampers, tuned liquid dampers, active/semi-active and hybrid mass dampers.

(3) A viscous liquid damper is arranged. The high-viscosity material is utilized to generate resistance force which is proportional to the speed of the main body when the structure is in dynamic response, and the resistance force is opposite to the movement direction of the main body structure, so that wind-induced vibration is controlled. The viscous liquid damper comprises an oil damper, a damping wall, an electrorheological damper, a magnetorheological damper and the like.

(4) A viscoelastic damper is provided. Some polymeric materials have viscous characteristics that dissipate energy through heat loss when subjected to shear, and dampers utilizing this property can reduce the amplitude of the dynamic structural response and reduce the acceleration level under wind forces.

In the prior art, a damping device is a spiral structure shown in fig. 1, and a continuous spiral wind guiding eave is manufactured from top to bottom outside a building body, so that the resistance of wind flow on the surface of the main body of the building body is reduced to a greater extent, and the stability of the building body is kept.

Although aerodynamic shape modification is extremely effective in the prior art, for buildings, the aesthetic concept is strictly considered when any switch is selected, and if aerodynamic shape modification is carried out, the aerodynamic shape modification must be carried out in early design and must meet the requirements of aesthetics and functions, so that the difficulty is greatly increased. The inertial damper is widely applied, but mainly depends on the mass of the damper to generate a damping effect, and usually the damper with huge mass needs to be installed at a higher position of a high-rise building, so that the inertial damper occupies space and is inconvenient to install, and the problem of fatigue failure of the damper and a main body structure connecting piece can also exist. Viscous liquid dampers are not trivial in effect, do not need extremely large mass, but are high in manufacturing cost, need to be distributed in a supporting system of the whole structure, are complex in construction, and have the hidden trouble that the effect is weakened or even fails due to power failure in extreme weather because active or semi-active control is needed for some types of dampers.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a bionic-based pneumatic damping device applied to a high-rise building and the high-rise building applying the device, solves the problems of poor universality and poor technical effect of the conventional pneumatic structure for improving the flutter stability in the high-rise building, obviously improves the overall flutter stability of the high-rise building, prolongs the service life of the building and reduces risks.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: the utility model provides a pneumatic fairing of modularization based on bionics, includes spatial grid structure and the blade that attaches to spatial grid structure, spatial grid structure is rigid material, the blade all is flexible material, all movable mounting has in each net of spatial grid structure the blade, the size of blade with each net size suits.

Further, a bayonet is reserved in each grid of the net rack, one end of each blade is a steel frame, and the steel frame is installed in the bayonet so as to install the blades in the grids.

Further, at least one of the blades is installed in a direction different from the other blades so that an array of the plurality of blades is randomly deformed by wind to reduce wind resistance, and energy is consumed by flapping of the blades to suppress structural vibration.

Further, bolt holes are reserved in each unit net rack so as to connect the net racks.

Furthermore, each grid of the grid structure is one or a combination of several of a square shape, a rectangular shape, a circular shape or an oval shape.

Further, the shape of the blade is one or a combination of a plurality of square, rectangle, circle or ellipse.

A high-rise building provided with a bionic-based modularized pneumatic resistance reducing device is characterized in that the pneumatic resistance reducing device is wholly or partially covered on the outer surface of the high-rise building, and one surface of each blade needs to face outwards.

Furthermore, the pneumatic drag reduction device is of a modular structure, and a plurality of modular structures are combined to form a whole according to the area required to be covered by the building.

Furthermore, the surface of the damping device can be provided with a heat preservation or lamp decoration structure.

(III) advantageous effects

The invention provides a bionic-based modular pneumatic resistance reducing device and a high-rise building using the same, and the device has the following beneficial effects: each blade can independently deform and vibrate, the aerodynamic appearance can be adaptively changed under the action of different winds, the wind resistance is reduced under various conditions, the blades are allowed to vibrate, the energy can be consumed while the resistance is reduced, and the wind-induced vibration of a high-rise building structure is further reduced. Because the deformation and the vibration are completely self-adaptive, compared with an active control scheme, the method omits a mechanical control device and is simpler.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic diagram of a prior art fairing for a high-rise building;

FIG. 2 is a schematic diagram of a grid structure of a pneumatic drag reduction device according to an embodiment of the present invention;

FIG. 3 is a schematic view of a blade configuration of an aerodynamic fairing according to an embodiment of the invention;

FIG. 4 is a schematic view of an installed blade configuration of an aerodynamic fairing according to an embodiment of the invention;

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.

Fig. 2 is a schematic diagram of a net rack structure of the pneumatic drag reduction device, fig. 3 is a schematic diagram of a blade structure of the pneumatic drag reduction device, and fig. 4 is a schematic diagram of a structure of the pneumatic drag reduction device after the blades are installed. The utility model provides a pneumatic fairing of modularization based on bionics, includes spatial grid structure and the blade that attaches to spatial grid structure, spatial grid structure is rigid material, the blade all is flexible material, all movable mounting has in each net of spatial grid structure the blade, the size of blade with each net size suits.

The principle is as follows: based on bionics, the method is different from the previous method of directly researching interaction between airflow and a structure and providing measures, and the method is provided according to the phenomenon of wind resistance of plants in nature.

The efficacy is as follows: can comprehensively improve the wind resistance of high-rise buildings. The wind-induced vibration control system can simultaneously control various wind-induced vibrations of high-rise buildings, directly reduces resistance, and can consume energy under the action of wind. The application can also meet the aesthetic requirements of buildings, optimize the pneumatic appearance of the buildings on the premise of not influencing the use function, and can also increase the functions of heat preservation, decoration and the like.

Maintenance: the small units are assembled into a large device, and when a device in a certain small area has a problem, only the module in the area can be conveniently disassembled for maintenance or replacement, so that the high-altitude operation amount is reduced, and the maintenance cost is reduced. Because the blades and the net rack are also designed separately, the number of the blades can be increased or decreased and the attachment positions of the blades can be changed at any time according to the opinion of owners so as to meet the requirements of personnel in the building and the wind resistance.

When wind passes through a high-rise building, the flexible blades change the shape along with the wind, so that the wind resistance is reduced, the flexible blades start to vibrate at the same time, the energy in the wind is continuously dissipated, the energy finally transmitted to a building structure is smaller than the total energy input by the wind, the excited structural vibration is reduced, and the airflow on the surface of the high-rise building is disturbed due to different shapes and a plurality of blades, so that the pulsation degree is reduced, and the buffeting force is reduced; on the other hand, only tiny vortexes can be formed, and the vortex-induced force periods are different, so that vortex-induced resonance is avoided; at the moment, the shape on the longitudinal section is also deformed compared with the building shape, and the vortex shedding synchronism can be broken to reduce the vortex shedding load. The effects of obviously reducing the amplitude of the high-rise building, improving the safety of the building and improving the comfort of high-rise personnel are achieved under the combined action of the above conditions.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical scope of the present invention and the equivalent alternatives or modifications according to the technical solution and the inventive concept of the present invention within the technical scope of the present invention.

Claims

1. The utility model provides a pneumatic fairing of modularization based on bionics which characterized in that: include spatial grid structure and the blade that attaches to spatial grid structure, spatial grid structure is rigid material, the blade all is flexible material, all movable mounting has in each net of spatial grid structure the blade, the size of blade with each net size suits.

2. The biomimetic-based modular pneumatic drag reduction device according to claim 1, characterized in that: the bayonet socket is reserved in each grid of the grid structure, one end of each blade is a steel frame, and the steel frame is installed in the bayonet socket so as to install the blades in the grids.

3. The biomimetic-based modular pneumatic drag reduction device according to claim 1, characterized in that: at least one of the blades is mounted in a direction different from the other blades so that an array of a plurality of the blades is randomly deformed by the wind to reduce the wind resistance, and energy is consumed by the flapping of the blades to suppress the structural vibration.

4. The biomimetic-based modular pneumatic drag reduction device according to claim 1, characterized in that: bolt holes are reserved in each unit net rack so as to connect the net racks.

5. The biomimetic-based modular pneumatic drag reduction device according to claim 1, characterized in that: each grid of the grid structure is one or a combination of several of a rectangle, a circle or an ellipse.

6. The biomimetic-based modular pneumatic drag reduction device according to claim 1, characterized in that: the shape of the blade is one or a combination of a plurality of rectangular, round or oval.

7. A high-rise building provided with a biomimetic-based modular pneumatic drag reduction device according to any of claims 1-6, characterized in that: and covering the pneumatic drag reduction device on the outer surface of the high-rise building wholly or partially, wherein one surface with the blades is required to face outwards.

8. The high-rise building of claim 7, wherein: the pneumatic drag reduction device is of a modular structure, and a plurality of modular structures are combined to form a whole according to the area required to be covered by the building.

9. The high-rise building of claim 7, wherein: the surface of the damping device can be provided with a heat preservation or lamp decoration structure.