1. The utility model provides an utilize wind-tunnel precooling apparatus of outdoor low temperature environment, its characterized in that, wind-tunnel precooling apparatus installs on the wind-tunnel, wherein, wind-tunnel precooling apparatus includes intake stack (2) and air-out pipeline (1), intake stack (2) and air-out pipeline (1) homogeneous end link the ventilation tunnel inside, one end intercommunication outside air.

2. The wind tunnel precooling apparatus using the outdoor low-temperature environment as claimed in claim 1, wherein the air inlet duct (2) and the air outlet duct (1) both comprise a duct body and a fan, and the fan is installed in the duct body and is controlled in rotation speed and rotation direction by an operation room of the wind tunnel.

3. The wind tunnel precooling apparatus using the outdoor low-temperature environment as claimed in claim 1, wherein the duct openings of the air inlet duct (2) and the air outlet duct (1) are both provided with automatic closing means for closing and opening the duct openings of the air inlet duct (2) and the air outlet duct (1).

Background

Under the background that extreme low temperature ice and snow disasters frequently occur in the world, the collapse accidents of buildings and structures caused by snow accumulation are increased, and the snow resistance situation of the building structure is very severe. The large-span space structure has the characteristics of light roof structure, large roof area and large proportion of snow load to total load, is usually controlled by snow load, and belongs to a structure sensitive to the snow load. On the other hand, the large-span space structure is mostly applied to public buildings such as stadiums, airport terminals, railway stations, and the like, which are very dense in personnel and have a great influence, so that the engineering disaster result caused by snow of the large-span space structure is very serious, and the design method for correctly mastering the roof snow load is of great significance.

In the 20 th century and the 60 th era, foreign scholars firstly developed the research on the snow load of buildings and gradually became a system, and three complementary research technical means of field actual measurement, numerical simulation and experimental research are gradually formed. The field actual measurement research is severely limited by regions, seasons and natural conditions, the research period is long, the randomness is large, the variable is uncontrollable, and the field actual measurement research is difficult to be used for revealing the multi-factor overall process evolution mechanism of the accumulated snow on the roof; the numerical simulation lacks a reliable standard test for verifying a model and a result of the numerical simulation, so that the application and popularization of the numerical simulation are greatly limited; based on the above limitations of the field actual measurement and numerical simulation method, experimental research completed in a laboratory according to a certain similar proportional relationship by means of manual equipment becomes an object for the development of scholars at home and abroad. The test research is not limited by natural conditions, regions or seasons, can control various parameters according to needs, realize parameter analysis and restore the process of snowfall or snow accumulation, can conveniently repeat the test, and becomes the most effective means for revealing the accumulation mechanism and the change rule of the snow accumulation on the roof.

Depending on the type of test object and equipment, the current experimental research methods can be divided into 3 types: the test method is based on a traditional wind tunnel and simulation particles, the test method is based on a water tank and simulation particles, and the wind and snow combined test method is based on a low-temperature wind tunnel and natural snow or artificial snow. A test method based on a traditional wind tunnel and simulated particles is a wind-induced snow drift test research carried out in the traditional wind tunnel by seeking a snow particle substitute, and sodium bicarbonate, fine silica sand, industrial salt and the like are generally adopted as the simulated particles; the test method based on the water tank and the simulation particles is a test method for simulating wind-induced snow drift by using a sand-water mixture in the water tank, and the density ratio of sand-water is closer to that of snow-gas, so that the establishment of a similarity criterion is more convenient, and the test method has lower popularity due to higher complexity and less quantity of water tank equipment; a wind and snow combined test method based on low-temperature wind tunnel and natural snow or artificial snow utilizes the low-temperature environment of a cold region in winter, and real snow particles or artificial snow particles are scattered and fall into a test section through a vibrating screen snowing simulation device, so that the test environment of stable snowing is realized, and the real snowing process is restored.

The real accumulation and evolution process of the accumulated snow on the roof is a very complex physical process, and is not only influenced by the drift phenomenon of wind-induced snow, but also influenced by various natural effects such as rain and snow combined action, thermal snow melting action and the like; not only by a single fall, but more often by the accumulation of multiple falls. However, the current related test equipment at home and abroad can hardly realize accurate simulation of the complex process, and most of the test equipment only researches the wind-induced snow drift phenomenon and the influence of single snowfall. In order to correctly reveal the accumulation and evolution mechanism of the accumulated snow on the roof, the combined influence of environmental factors such as wind, rain, heat and the like in the nature must be considered, and the whole process of accumulation, ablation, crystallization and accumulation evolution of the accumulated snow on the roof is simulated. Therefore, the low-temperature wind tunnel of the atmospheric boundary layer of the building engineering and artificial snow or natural snow must be used for testing.

At present, functionally similar experimental facilities known from the literature are only the Jules Verne (JV) meteorological wind tunnel in south france (see fig. 1a) and the japan new village freezing circle environmental simulation laboratory (CES) (see fig. 1 b).

The French south Te JV meteorological wind tunnel consists of an inner circulation wind tunnel and an outer circulation wind tunnel, wherein the outer circulation wind tunnel is called a dynamic ring, and the French south Te JV meteorological wind tunnel is provided with three test sections (a multi-environment simulation test section, a low wind speed test section and a high wind speed test section). The multi-environment simulation test section is mainly used for researching the response of the building in wind, rain and sand storm environments, and the maximum wind speed can reach 90 km/h; the other two test sections are provided with force measuring balance and the like, and are mainly used for measuring wind vibration response (lift coefficient, resistance coefficient) and surface wind pressure and the like of building structures and traffic facilities, the maximum wind speed of the low wind speed section is 160km/h, and the maximum wind speed of the high wind speed section can reach 280 km/h. The inner ring is also called a temperature control ring (thermal circuit), heat exchange equipment is arranged in the inner ring, the temperature of an environment test section can be controlled to be-32-55 ℃, the inner ring can be used for simulating the atmospheric environment such as rain, snow, solar radiation and the like, the cross section size of the test section is 10m multiplied by 7m, the length is 25m, and the maximum wind speed can reach 140 km/h.

The CES laboratory of Nippon Xinzhuang is provided with a wind tunnel with the section of 1m multiplied by 1m and the test section length of 14m, and the test section can maintain the low-temperature environment of minus 10 ℃ by convection of a refrigerator and a fan. The CES laboratory can manually manufacture hexagonal tree-shaped snow particles and spherical snow particles, can simulate the snow falling process through the vibration scattering device, and can adopt a pre-particle-spreading method to carry out experimental research on wind-induced snow drift. The temperature control method of the test system is similar to that of a French JV meteorological wind tunnel, and the precooling process of the test system and the French JV meteorological wind tunnel is realized by manufacturing low-temperature air through air conditioning equipment to precool a wind tunnel test section, so that the external low-temperature environment is not directly utilized, and the cost is overhigh.

The invention belongs to the field of building snow load, and is directly applied to the precooling process of a low-temperature wind tunnel of an atmospheric boundary layer of building engineering. The aim is to integrally pre-cool the whole wind tunnel by utilizing the outdoor low-temperature environment of Harbin in winter according to local conditions, achieve the low-temperature environment required by artificial snow or natural snow tests, and overcome the defect of overhigh temperature control cost of the low-temperature wind tunnel of the atmospheric boundary layer of the existing building engineering.

Disclosure of Invention

The invention aims to provide a wind tunnel precooling device utilizing an outdoor low-temperature environment, which aims to solve the problems that the conventional wind tunnel needs to manufacture low-temperature air through air conditioning equipment in a precooling process to precool a wind tunnel test section, so that the external low-temperature environment is not directly utilized, and the energy consumption cost is overhigh.

The utility model provides an utilize wind-tunnel precooling apparatus of outdoor low temperature environment, wind-tunnel precooling apparatus installs on the wind-tunnel, wherein, wind-tunnel precooling apparatus includes intake stack and air-out pipeline, intake stack and air-out pipeline homogeneous end link the ventilation tunnel inside, and one end communicates the outside air.

Furthermore, the air inlet pipeline and the air outlet pipeline both comprise a pipeline body and a fan, and the fan is installed in the pipeline body and is controlled in rotation speed and rotation direction by the operation room of the wind tunnel.

Furthermore, automatic closing devices are installed at the pipeline openings of the air inlet pipeline and the air outlet pipeline and used for closing and opening the pipeline openings of the air inlet pipeline and the air outlet pipeline.

The invention has the following advantages: the invention provides a wind tunnel precooling device utilizing outdoor low-temperature environment, which can utilize the outdoor low-temperature environment in winter in cold regions according to local conditions to precool a wind tunnel, the cost is greatly reduced compared with the cost of a precooling mode of other existing similar equipment, and the electricity consumption can be reduced by about 1200 Kw.h in each test through preliminary measurement and calculation.

Drawings

FIG. 1 is a schematic structural diagram of two conventional wind tunnels, wherein FIG. 1(a) is a schematic structural diagram of a French JV meteorological wind tunnel; FIG. 1(b) is a schematic view of a structure of a Japanese CES wind tunnel;

FIG. 2 is a schematic structural diagram of a main body of a wind tunnel precooling apparatus utilizing an outdoor low-temperature environment according to the present invention;

FIG. 3 is a schematic diagram of a wind tunnel precooling apparatus utilizing an outdoor low-temperature environment according to the present invention before a test is started;

fig. 4 is a schematic diagram of a state of the wind tunnel precooling apparatus using the outdoor low-temperature environment according to the present invention after a test is started.

Wherein, 1 is an air outlet pipeline, 2 is an air inlet pipeline, 3 is a test section, 4 is a diffusion section, 5 is a power section, 6 is a transition section, 7 is a third corner, and 8 is a fourth corner.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying 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, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, in the present embodiment, a wind tunnel precooling apparatus using an outdoor low-temperature environment is provided, where the wind tunnel includes a test section 3, a diffuser section 4, a power section 5, a transition section 6, a third corner 7 and a fourth corner 8, the test section 3, the diffuser section 4, the third corner 7, the fourth corner 8, the power section 5 and the transition section 6 are sequentially communicated,

the wind tunnel precooling device comprises an air inlet pipeline 2 and an air outlet pipeline 1, the air inlet pipeline 2 is installed between a third corner 7 and a fourth corner 8, the air outlet pipeline 1 is installed between a power section 5 and the fourth corner 8, the uniform ends of the air inlet pipeline 2 and the air outlet pipeline 1 are communicated with the interior of the wind tunnel, and the other ends of the air inlet pipeline 2 and the air outlet pipeline 1 are communicated with the outside air.

In particular, a wind tunnel is a duct that generates artificial airflow for studying the aerodynamic effects of air flowing through an object. The common wind tunnel is of a vertical single-backflow closed type and comprises a stable section (comprising a honeycomb device and a damping net), a contraction section, a test section, a first diffusion section, a first corner, a second corner, a first transition section, a second transition section, a square-circle transition section, a power section, a round-square transition section, a third diffusion section, a third corner, a third transition section, a fourth corner and the like. In other embodiments, the wind tunnel precooling device may be installed at any section of the wind tunnel, a hole is opened at an installation position on the wind tunnel, and a pipeline and a fan are installed to connect with an external low temperature environment. The number of the pipelines is two, one pipeline is an air inlet pipeline 2 and is used for introducing external low-temperature air; and the second is an air outlet pipeline 1 used for exhausting the air at the room temperature inside.

Further, the air inlet pipeline 2 and the air outlet pipeline 1 both comprise a pipeline body and a fan, and the fan is installed in the pipeline body and is controlled in rotation speed and rotation direction by the operation room of the wind tunnel.

Further, the pipeline openings of the air inlet pipeline 2 and the air outlet pipeline 1 are both provided with automatic closing devices for closing and opening the pipeline openings of the air inlet pipeline and the air outlet pipeline.

Specifically, before the snowfall simulation test is carried out in winter, the precooling device is started, low-temperature air is introduced, room-temperature air is discharged, and the temperature inside the cave body is reduced rapidly at low cost through convection heat exchange so as to reach the temperature range of-20 ℃ to-5 ℃ required by the test.

Fig. 2 shows a schematic diagram of a main structure of a wind tunnel, which belongs to a part of the main structure, and is a wind tunnel precooling device utilizing an outdoor low-temperature environment, and the wind tunnel precooling device consists of an air inlet pipeline 2 and an air outlet pipeline 1.

Before the test starts, the air inlet pipeline 2 and the air outlet pipeline 1 are opened, the fan is started, outdoor cold air is introduced, warm air in the cavity is discharged, and the wind tunnel is cooled, as shown in fig. 3.

And when the temperature in the cavity body reaches the test required temperature, closing the fan, closing the inlet of the air inlet and outlet pipeline, and performing the test, as shown in fig. 4.

The above embodiments are only used to help understanding the method of the present invention and the core idea thereof, and a person skilled in the art can also make several modifications and decorations on the specific embodiments and application scope according to the idea of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.