CN102563796B - Safe escape system for closed airflow channel in middle of building member - Google Patents

Abstract

The invention discloses a safe escape system for a closed airflow channel in the middle of a building member. The system comprises a first static pressure box, a first nozzle, a second nozzle, a third nozzle, a second static pressure box, a fourth nozzle, a fifth nozzle, a sixth nozzle, a ventilation pipeline and a fan. The system is characterized in that the first nozzle, the second nozzle and the third nozzle are connected with the first static pressure box, the fourth nozzle, the fifth nozzle and the sixth nozzle are connected with the second static pressure box, the first static pressure box and the second static pressure box are connected by virtue of the ventilation pipeline, and the ventilation pipeline is connected with the fan. In the safe escape system for the closed airflow channel in the middle of the building member, due to a unique design of the system, six groups of air flow which mutually clash can be generated, piston flow is generated by clash among the air flow, thus smoke in a special area can be removed, a safe and clean channel can be formed in the building member, and finally a clean and safe living channel can be created for personnel.

Description

Safety escape system for closed passage of airflow in the middle of building components

technical field

The invention relates to a personnel escape system, in particular to a safety escape system for an airflow closed channel in the middle of a building component.

Background technique

A large amount of smoke will be produced after a fire, and high-temperature smoke is the main cause of death in a fire. Since the flue gas is at a higher temperature than the environment, its density will be lower than that of air. The low smoke density compared to the surrounding air creates a buoyant force which causes the smoke to move upwards. When the flue gas moves upwards and hits the ceiling, the flue gas that touches the ceiling later will push the flue gas that touched the ceiling before. This results in a horizontal movement of the smoke along the ceiling, which smoke studies have shown to be very dangerous as it carries the smoke to various places in the building elements.

Studies have shown that for building elements or multi-storey buildings, the height of the smoke will decrease continuously due to the accumulation of the smoke on the top of the space. This will greatly reduce the space for people to escape, see Figure 1. This can make it difficult for people in the building to escape. Thereby causing great loss of personnel and property. If after a fire occurs, a clean, low-temperature area without smoke can be formed in the building through various technical means, which will greatly facilitate the escape of personnel. Improve personnel safety after a fire. Thereby minimizing the loss of personnel and property.

Current research shows that no smoke prevention and exhaust system can 100% eliminate fire smoke caused by fire. The existing smoke prevention system for building components mainly adopts the method of setting smoke exhaust outlets on the top of the building to exhaust the smoke, so as to dilute the smoke in the building and reduce the indoor smoke concentration. However, the current existing technology has the following problems: question:

1. Flue gas dilution is not completely eliminated. Most of the flue gas still exists in the building, and this part of the flue gas will also cause loss of personnel and property.

2. The flue gas dilution effect does not directly depend on the power of the exhaust fan, that is, the greater the exhaust fan exhaust volume, the more effective it is. Because of the suction force of the exhaust fan, a negative pressure will be formed in the building, that is, the building will The pressure inside the building is greater than that outside, and in this case the smoke exhaust fan will not be able to completely extract the smoke from the building.

Aiming at the technical shortcomings of the existing technology to exhaust smoke simply through the smoke exhaust outlet, the applicant applied for an invention patent in 2010, the name of the invention is a smoke prevention system for stairwells (patent application number: 201010580513.6). Improvements were made. Based on the scientific concept of "blocking is worse than sparse", the applicant created a counter jet area through six independent "jet" nozzles, thereby effectively preventing the entry of smoke, and finally achieved the effect of releasing smoke. .

With the applicant's further research on this topic, the applicant found that the above system still has the following technical defects:

1. Although the earlier application was able to stop the fumes from entering the protected area through the "jet" nozzle. However, due to the turbulence and random fluctuation of the flue gas, this makes the flue gas itself vary in size relative to the wind speed of each nozzle. As a result, the stairwell smoke prevention system only has a blocking rate of 70-80% (volume percentage) of smoke, so the remaining 20-30% (volume percentage) of smoke will enter the previously patented smoke protection area.

2. The previous application cannot rule out the smoke passing through the "jet" nozzle and hitting the jet area. On the contrary, due to the action of multiple jet nozzles up and down, the diffusion of the smoke passing through the jet area will be accelerated.

3. Since the previous application cannot exclude the smoke passing through the collision jet area, its main design purpose is to enhance the smoke blocking efficiency of the smoke prevention system. There are three pairs of six nozzles for the smoke prevention system in the earlier application. Through the later research and practice, we found that the technical improvement design of the earlier application increases the initial investment capital, manufacturing difficulty and operating cost of the system.

Contents of the invention

Aiming at the defects or deficiencies in the prior art and the applicant’s previous application, the purpose of the present invention is to provide a safety escape system for airflow closed channels at the sides of building components. The unique design of the airflow closed channel safety escape system in the middle of building components can generate mutual Four sets of air streams colliding. Firstly, the jet area is formed by blowing against each other through the common tuyere, and the entry of smoke is prevented through the jet area. Secondly, the positive pressure zone is formed by blowing against the gradually expanding nozzle. This positive pressure zone will act as a smoke-proof "backup" for the jet zone. While the blocking rate of the device to the smoke can be increased, the smoke entering the smoke protection area due to the turbulence of the smoke can be eliminated.

The object of the present invention is to provide a safety escape system for the closed passage of airflow in the middle of a building component. The unique design of the safety escape system for the closed passage of airflow in the middle of the building component can generate six groups of airflows colliding with each other. . Generate plug flow to "drive away" the smoke in a specific area, and then create a safe and clean passage in the middle of the building components, and finally create a clean and safe way for people to escape.

In order to achieve the above object, the present invention adopts the following technical solutions to achieve:

A safety escape system for a closed air passage in the middle of a building component, comprising a first plenum box and a second plenum box, the first plenum box and the second plenum box are symmetrically arranged in parallel, the first plenum box and the second plenum box The two static pressure boxes are connected through ventilation ducts, and the ventilation ducts are connected with fans;

The lower end of the first static pressure tank is provided with a first nozzle, a second nozzle and a third nozzle, wherein the first nozzle and the third nozzle are respectively located on both sides of the second nozzle; the upper end of the second static pressure tank is provided with a fourth nozzle , the fifth spout and the sixth spout, wherein the fourth spout and the sixth spout are respectively located on both sides of the fifth spout;

The first nozzle, the second nozzle and the third nozzle are respectively arranged symmetrically with the fourth nozzle, the fifth nozzle and the sixth nozzle along the horizontal direction, and the outlet direction of the second nozzle and the fifth nozzle is opposite to the vertical direction, The air outlet directions of the first nozzle and the fourth nozzle intersect, and the outlet directions of the third nozzle and the sixth nozzle intersect.

Other technical characteristics of the present invention are:

The second nozzle and the fifth nozzle supply air along the vertical direction, the angle between the first nozzle and the fourth nozzle and the vertical direction is 1°~5°, and the angle between the third nozzle and the sixth nozzle and the vertical direction is 1° ~5°, and the first nozzle and the fourth nozzle, the fourth nozzle and the sixth nozzle are arranged symmetrically along the vertical direction.

The second spout and the fifth spout are expanding spouts, and the area ratio between the outlet of the expanding spout and the entrance is 5:1; the outlets of the second spout and the fifth spout are respectively connected to the first spout, The area ratio of the outlets of the third nozzle, the fourth nozzle and the sixth nozzle is 5:1; the longitudinal distance between the outlet of the second nozzle and the fifth nozzle is less than 3m; the distance between the second nozzle and the fourth nozzle is less than 3m.

In the present invention, the first spout, the third spout, the fourth spout and the sixth spout are symmetrically arranged and all adopt inclined air supply, so that the air supply of the first spout and the fourth spout, the third spout and the sixth spout collide with each other, Offset the vertical velocity component of the air supply, thereby forming the horizontal direction of the air piston to move, the technical effect of the piston moving, blocking the smoke and entraining the incoming smoke in the upper space within its range of action; at the same time, the present invention passes through the second The nozzle and the fifth nozzle are set up and down opposite to each other and both adopt vertical air supply. The second nozzle and the fifth nozzle with gradually expanding nozzle have a large air supply area and a small air supply speed and are in a collision state. After the up and down collision, the fluid carried by the fluid itself A large part of the dynamic pressure or momentum will be lost, and this part of the lost dynamic pressure or momentum will be directly converted into a pressure difference in this area relative to the entire channel, thereby forming a positive pressure area. The design of the gradually expanding nozzles of the second nozzle and the fifth nozzle above, the flow field formed by the air outlet is completely different from the flow field formed by the small air outlet of the jet nozzle in the previous application. The jet flow described here The nozzles, that is, the small air outlets are the first nozzle and the fourth nozzle, the third nozzle and the sixth nozzle. After the collision of the small air outlets, due to the excessive momentum, the momentum loss is relatively small compared to the momentum carried by itself. This makes the dynamic pressure conversion static pressure incomplete after the upper and lower sides of the small air outlet collide, thus forming a push flow toward the channel, that is, the above-mentioned mixing zone, see Figure 2, the first nozzle and the fourth nozzle, the first The colliding jet formed by the third nozzle and the sixth nozzle can effectively block the entry of smoke due to its relatively large momentum. At the same time, the second nozzle and the fifth nozzle can effectively return the smoke pressure in the jet flow area formed by the first nozzle and the fourth nozzle, the third nozzle and the sixth nozzle to In the channel, it finally played the role of forming a safe channel.

Compared with the prior art, the present invention has the following technical advantages:

1. Due to the effect of the positive pressure zone formed by the blowing of the second nozzle and the fifth nozzle, the present invention can effectively eliminate the smoke entering the area, rather than just preventing the smoke from entering. Therefore, considering comprehensively, the smoke blocking rate of the present invention is close to 100%.

2. The present invention is a personnel escape channel composed of airflow, so it does not occupy the building volume, and there is no component of the present invention to block the escape of people when personnel escape.

3. Due to the effect of the positive pressure area, the present invention can eliminate the smoke entering the smoke prevention area, so there is no need to set more inclined air outlets, only the first and third air outlets are needed. Therefore, compared with the previous application for the stairwell smoke prevention system (201010580513.6), its cost is lower, the system is simpler, and the operating cost is also lower.

Description of drawings

Figure 1a is a schematic diagram of the smoke concentration distribution on the longitudinal section 10m away from the fire source; Figure 1b is a schematic diagram of the smoke concentration distribution on the longitudinal section 5m away from the fire source; Figure 1c is the smoke concentration distribution on the longitudinal section at the fire source schematic diagram.

Fig. 2 is a schematic diagram of the air supply direction of the safety escape system of the airflow closed channel at the side of the building component of the present invention.

Fig. 3 is a structural schematic diagram of the safety escape system of the airflow closed channel at the side of the building component of the present invention.

Fig. 4 Schematic diagram for calculation of optimal ratio of outlet and inlet area of expanding nozzle.

Figure 5 is a schematic diagram of the smoke concentration in the smoke protection area under different longitudinal distances from the nozzle.

Figure 6 is a schematic diagram of the smoke blocking rate of the smoke discharge system under different angles between the blowing port and the numerical direction.

Fig. 7 is a schematic diagram of the optimal air supply velocity ratio of different air supply outlets in the present invention.

Figure 8a is a schematic diagram of the smoke concentration distribution on the longitudinal section 10m away from the fire source; Figure 8b is a schematic diagram of the smoke concentration distribution on the longitudinal section 5m away from the fire source; Figure 8c is the smoke concentration distribution on the longitudinal section at the fire source Schematic diagram of the distribution; Figure 8d is a schematic diagram of the smoke concentration distribution on the cross section at a height of 2m from the ground 240 seconds after the fire broke out.

Figure 9. Velocity field schematic diagram of the earlier application "Stairwell Smoke Prevention System (201010580513.6)"

Figure 10 is a schematic diagram of the smoke concentration in the smoke protection zone of this patent compared with the previous application "Smoke Prevention System for Stairwells (201010580513.6)".

The specific implementation manners of the present invention will be described in further detail below in conjunction with the accompanying drawings.

Detailed ways

The building components referred to in the application documents of the present invention refer to building interior space elements with certain shapes, such as cubes, cylinders, and cones, such as atriums, corridors, and platforms.

As shown in Figure 3, the airflow closed channel safety escape system in the middle of the building component of the present invention is a kind of airflow closed channel safety escape system in the middle of the building component, comprising a first static pressure box 1 and a second static pressure box 8, the first The static pressure box 1 and the second static pressure box 8 are symmetrically arranged in parallel, and the first static pressure box 1 and the second static pressure box 8 are connected through a ventilation duct 9, and the ventilation duct 9 is connected to the fan 10;

The lower end of the first static pressure tank 1 is provided with a first spout 2, a second spout 3 and a third spout 4, wherein the first spout 2 and the third spout 4 are respectively located on both sides of the second spout 3; The upper end of the box 8 is provided with a fourth spout 5, a fifth spout 6 and a sixth spout 7, wherein the fourth spout 5 and the sixth spout 7 are respectively located on both sides of the fifth spout 6;

The first spout 2, the second spout 3 and the third spout 4 are respectively arranged symmetrically with the fourth spout 5, the fifth spout 6 and the sixth spout 7 along the horizontal direction, and the second spout 3 and the fifth spout 6 are The wind direction is opposite along the vertical direction, the wind outlet direction of the first nozzle 2 and the fourth nozzle 5 intersect, and the wind outlet direction of the third nozzle 4 and the sixth nozzle 7 intersect.

The second nozzle 3 and the fifth nozzle 6 blow air along the vertical direction, the angle between the first nozzle 2 and the fourth nozzle 5 and the vertical direction is 1°～5°, the third nozzle 4 and the sixth nozzle 7 The included angle with the vertical direction is 1°-5°, and the first spout 2, the fourth spout 5, the fourth spout 5 and the sixth spout 7 are arranged symmetrically along the vertical direction, respectively.

The second spout 3 and the fifth spout 6 of the present invention are expanding type spouts, and the area ratio of the expanding type spout exit and the entrance is 5: 1, the exit of the second spout 3 and the fifth spout 6 is the same as the first spout. The area ratio of the outlets of the second nozzle 3 and the fifth nozzle 6 is 5:1. The reason why the ratio of 5:1 is taken is that when the ratio is larger, the dynamic pressure at the outlet of the nozzle is converted into static pressure more thoroughly, and the more thorough momentum conversion will bring greater static pressure, thus forming a better The positive pressure zone, and then better eliminate the smoke entering its interior. However, an excessively large export area will bring a greater cost. And when the area ratio of the outlet and the inlet of the gradually expanding nozzle is 5:1, the skill can ensure a good ratio of dynamic pressure to static pressure, and can ensure that the cost is not too high. The schematic diagram of cost and dynamic pressure conversion efficiency ratio is shown in Figure 4. It can be seen from the figure that the optimal ratio of the area of the outlet of the expanding nozzle to the area of the inlet is 5:1, which is the ratio selected by the present invention.

The longitudinal distance between the first nozzle 2 and the fourth nozzle 5 is less than 3m; the longitudinal distance between the second nozzle 3 and the fifth nozzle 6 is less than 3m. The longitudinal distance between the third nozzle 2 and the sixth nozzle 5 is less than 3m; when the air volume is constant, if the longitudinal distance between the nozzles is too large, the jets ejected from the nozzles cannot collide, so that the jet area and positive pressure cannot be formed Area, and then can not effectively remove the smoke. Figure 5 shows the change of the smoke in the smoke protection area as the longitudinal distance between the nozzles increases. It can be seen that the smoke concentration increases significantly after the distance of 3m. Therefore, in this patent, the longitudinal distance between the spouts is 3m. This distance is just enough to ensure the collision of the outgoing jets, thereby ensuring the formation of the positive pressure zone and the jets, and finally effectively exhausting the smoke.

When a fire occurs, the fan draws clean outdoor air and sends it into the first plenum box 1 and the second plenum box 8 through the ventilation duct. After passing through the static pressure box, the dynamic pressure of the air in the ventilation duct is converted into static pressure, so that the air evenly passes through the first nozzle 2, the second nozzle 3, the third nozzle 4, the fourth nozzle 5, the fifth nozzle 6 and the sixth nozzle. Spout 7. We know that the wind in any direction can be decomposed into the superposition of winds in the X direction, Y direction and Z direction with different sizes according to the vector principle. as follows:

Wind speed WS1(x, y, z)=u1(x)i+v1(y)j+w1(z)k

Wind speed WS2(x, y, z)=u2(x)i+v2(y)j+w2(z)k

The superposition of wind speed WS1 and WS2 is:

WS3(x, y, z)=[u1(x)+u2(x)]i+[v1(y)+v2(y)]j+[w1(z)+w2(z)]k

When two winds from different incoming directions collide, if there is no velocity component in the Z direction. When the velocities in the Y direction are equal, there are:

WS3(x, y, z)=[u1(x)+u2(x)]i+[v1(y)-v2(y)]j+[0+0]k

＝2×u1(x)i

That is to say: after these two wind speeds collide, only the horizontal wind speed will remain, and the wind speed in the vertical direction will cancel. The present invention utilizes this principle, and the first spout 2, the second spout 3, the third spout 4, the fourth spout 5, the fifth spout 6 and the sixth spout 7 supply air at the same time, so that the speed is the same and the direction is 90°. ° angle of the four jet areas. The air in the four jet areas counteracts the vertical velocity after colliding, leaving only the horizontal wind velocity, thus forming a piston flow in the middle of the building components, and finally forming a mixing area, as shown in Figure 2. In this way, the smoke in a specific area can be "driven away", thereby creating a safe and clean passage in the middle of the building components, and finally creating a clean and safe way for people to escape.

Simultaneously, the present invention is arranged up and down oppositely through the first spout and the fifth spout and all adopts vertical air supply, the first spout and the fifth spout area are large and the air supply speed is small and are in the colliding state, the kinetic energy carried by the fluid itself after the up and down colliding There will be a large part of the loss of pressure or momentum, and this part of the lost dynamic pressure or momentum will be directly converted into the pressure difference in this area relative to the entire channel, thus forming a positive pressure zone.

The first spout and the fifth spout of the present invention are gradually expanding spouts, and the flow field formed by it and the small air outlet is completely different. The small air outlet here refers to the first spout, the third spout, the fourth spout and the first spout. Six nozzles, after the small air outlet collides, due to the excessive momentum, the momentum loss is relatively small compared to the momentum carried by itself, which makes the dynamic pressure conversion static pressure incomplete after the upper and lower sides of the small air outlet collide. , so as to form a push flow toward the direction of the channel, that is, the mixing zone, as shown in Figure 2, which makes the colliding jets formed by the first nozzle, the third nozzle, the fourth nozzle and the sixth nozzle, due to the reason of relatively large momentum , can effectively block the entry of smoke, and at the same time, due to the large positive pressure of the first nozzle and the fourth nozzle, it can effectively pass through the jet flow area formed by the first nozzle, the third nozzle, the fourth nozzle and the sixth nozzle. The smoke pressure is returned to the channel, which finally plays the role of forming a safe channel.

At the same time, after further in-depth research, the applicant found that when the angle between the first nozzle and the fourth nozzle, the third nozzle and the sixth nozzle and the vertical direction is between 1° and 5°, the effect of the air supply on the flue gas The obstruction effect is the best. The above test conditions are to simply compare the air outlet angles of a single pair of nozzles without adding a positive pressure area, so as to eliminate the influence of the positive pressure area on the smoke obstruction effect, see Figure 6.

This is because if the included angle is too small, the converging point will deviate too far from the air supply position, and the flue gas will easily leak to the positive pressure area. If the included angle is too large, the wind speed in the horizontal direction is too small, which will also easily cause smoke leakage. And when the included angle between the second nozzle and the fourth nozzle and the vertical direction is 1°-5°, it can not only ensure a certain horizontal wind speed, but also ensure that the air supply distance is not too long. So as to play a good air supply effect.

The design of the included angle between the nozzle and the vertical direction in this application is mainly to avoid smoke leakage, ensure a certain horizontal wind speed and ensure that the air supply distance is not too long.

In addition, studies have shown that the air velocity ratio between the first nozzle and the second nozzle is particular. When the total air volume is constant, the air supply speed of the first nozzle increases, and the air supply speed of the second nozzle decreases; otherwise, the speed of the first nozzle decreases, and the air supply speed of the second nozzle increases. When the speed of the first nozzle increases, the "shielding" effect of the first nozzle on the smoke will be strengthened, and the second nozzle's air supply speed will decrease, and the driving effect on the smoke will decrease. On the contrary, the "shielding" effect of the first nozzle on the smoke will be reduced, while the driving effect of the second nozzle on the smoke will be strengthened. Therefore, the ratio of the air supply velocity between the first nozzle and the second nozzle has an optimal value. Studies have shown that when the ratio of the air supply velocity between the first nozzle and the second nozzle reaches 5:1, the CO concentration in the smoke protection area minimum, see Figure 7. Similarly, due to the symmetry effect, it can be seen that the optimal value of the air supply velocity ratio between the third nozzle and the fourth nozzle is also 5:1. The air supply areas of the first nozzle, the second nozzle, the third nozzle and the fourth nozzle can be obtained through the ratio of the air supply speed, see the following specific examples.

Studies have shown that if the angles between the first nozzle, the third nozzle, the fourth nozzle, and the sixth nozzle and the vertical direction are too small, the converging point will deviate too far from the air supply position, and the flue gas will easily leak to the positive pressure area. If the included angle is too large, the wind speed in the horizontal direction is too small, which will also easily cause smoke leakage. After the research of the patent designer, it is found that when the angles between the first nozzle, the third nozzle, the fourth nozzle and the sixth nozzle and the vertical direction are all between 1° and 5°, the technology of this patent system can guarantee a certain level. The wind speed can also ensure that the air supply distance does not reach the process, so as to achieve a good air supply effect, as shown in Figure 6.

At the same time, the positive pressure zone formed by the second nozzle and the fifth nozzle and the two jet regions respectively formed by the first nozzle and the fourth nozzle and the third nozzle and the sixth nozzle are mutually matched, and neither is dispensable.

First, if there is no jet flow zone, but only positive pressure zone. Even the second nozzle and the fifth nozzle can form a positive pressure zone. Due to the pulsation of the flue gas, part of the flue gas will continuously enter the positive pressure zone and be continuously pressed out by the pressure in the positive pressure zone. This will form a dynamic balance, that is, smoke will enter continuously, and smoke will be discharged if it does not work. This leads to the existence of smoke all the time in the smoke protection area, which will cause personal property damage. And when adding the jet flow area formed by the first jet port and the fourth jet port and the third jet port and the sixth jet port respectively, the jet flow area will play a shielding role for the smoke that wants to enter the smoke protection zone. Most of the flue gas is isolated, and the flue gas that slips through the screen will eventually be discharged by the positive pressure in the positive pressure area.

Secondly, if there is only a jet flow area, but no positive pressure area. Although the jet area can effectively shield the smoke, due to the pulsation of the smoke, its shielding effect is not 100%, which makes a part of the smoke directly enter the smoke protection zone. And for this part of the smoke that enters, because only the blowing direction of the jet area is opposite to the smoke protection area (the same time, there is no need for smoke protection, it will directly shame the indoor smoke into the dialect protection area, and it will not be able to play a protective role. ). This makes this part of the smoke at the back of the jet area, that is to say, the jet area cannot exclude it from the smoke protection area.

All in all, the jet flow area is equivalent to the gate of the positive pressure area, which effectively removes most of the smoke first. The positive pressure area is equivalent to the strong backing of the jet flow area, eliminating a small amount of delay due to flue gas pulsation. Both the jet flow area and the positive pressure area are indispensable. The two are complementary.

In the present invention, wherein the spouts of the second spout 3 and the fifth spout 6 have a gradual expansion, and its size is greater than that of the first spout 2, the third spout 4, the fourth spout 5 and the sixth spout 7, and. This design is mainly because the air volume sent to the plenum is constant, if the air volume sent by one row of nozzles is large, the air volume sent by another row of air outlets will be small. Under a certain air volume, how to reasonably set the size of the air supply port directly determines the cleanliness of the air in the flue gas channel. Since the first jet port 2 and the fourth jet port 5 and the third jet port 4 and the sixth jet port 7 are respectively on the two outer sides, the wind they send out needs to counteract a lot of smoke, and the counteracted smoke momentum is large, so the wind speed is large. It should be higher than the wind speed of the second nozzle and the fifth nozzle, and the wind speed of the second nozzle and the fifth nozzle is too large, which will affect the escape speed of personnel and give people an uncomfortable feeling. It is isolated outside the positive pressure zone, so under the same air volume, a gradual expansion is installed on the second nozzle 3 and the fifth nozzle 6, which can make the wind speed in the positive pressure zone appropriate, thereby achieving the best air supply effect.

Since the building components are escape routes, passing by is required. Therefore, the first plenum box and the second plenum box are respectively concealed on the suspended ceiling and the floor in the middle of the building component to facilitate the passage of personnel.

Specific examples:

Specific embodiments of the present invention are provided below, and it should be noted that the present invention is not limited to the following specific embodiments, and all equivalent transformations done on the basis of the technical solutions of the present application all fall within the scope of protection of the present invention.

Comply with the above technical solution, as shown in Figure 1 and Figure 2. Firstly, the ratio of the area at the entrance of the second nozzle to the area at the exit is 1:5. The air speed ratio is 5:1. Because the air supply speed is directly proportional to the nozzle area. This makes it possible to meet the above requirements when the area of the inlet of the second nozzle is equal to that of the inlet of the first nozzle (the areas of the outlet and inlet of the first nozzle are equal). Then when the area of the first nozzle is 30m×0.1m, the area of the second nozzle is 30m×0.5m. The size of the first static pressure box and the second static pressure box are both 30m×0.6m×0.4m, and the diameter of the ventilation pipe is 0.3m×0.3m. The air supply speed of the first nozzle and the third nozzle is 1m/s. The air supply volume is 3m ³ /s, and the air supply speed of the second nozzle and the fourth nozzle is 0.2m/s. The air supply volume is also 3m ³ /s. The total air supply volume of the whole system is 12m ³ /s. The above-mentioned first nozzle and the third nozzle are perpendicular to the static pressure tank, and the included angle between the second nozzle and the fourth nozzle and the vertical direction is the same and is 3°. All nozzles, that is, static pressure boxes, are embedded in the ceiling and under the ground at the edge of the channel.

Achieved effect:

Through the above solution, as shown in Fig. 1, when a fire occurs in a building component, due to the high temperature of the smoke and the low temperature of the surrounding air, the smoke moves upward. When the flue gas moves upwards and hits the ceiling, the flue gas that touches the ceiling later will push the flue gas that touched the ceiling before. This results in a horizontal movement of smoke along the ceiling which smoke studies have shown to be dangerous. In the present invention, the vertical air supply of the second nozzle 3 and the fifth nozzle 6 and the direction of the air outlet are opposite, and the oblique air supply of the first nozzle 2 and the fourth nozzle 5 and the third nozzle 4 and the sixth nozzle 7 are related to the vertical direction. The included angles are all 1°～5°, forming six groups of air flows colliding with each other, through the collision between the air flows. The vertical velocity component of the air supply is offset and the horizontal velocity component is superimposed. In this way, the air piston moves in the horizontal direction, and the incoming smoke is entrained in the upper space within its range of action, as shown in Figure 2. These six wind-force building components intersect each other, forming a positive pressure zone and four jet flow zones in the middle of the building component. While entraining the smoke in the upper half of the space and preventing it from moving toward the positive pressure zone, a clean bottom layer of air is formed in the middle of the building components, as shown in Figure 8. Create a safe and clean passage in the middle of the building components, and finally create a clean and safe way for people to escape.

In order to further verify the advanced nature of this application compared with the previous patent application, the experimental effect comparison was carried out between this patent and the previous patent application stairwell smoke prevention system (201010580513.6). The comparison between the two was carried out under the same experimental conditions, including the same smoke exhaust volume, the same static pressure box size, the same fire source position and the same heat release rate, etc.

1. From the point of view of the blocking rate of smoke, since the present invention cooperates with the positive pressure area and the jet flow area, it can not only effectively block the entry of smoke, but also remove the incoming smoke, as shown in Figure 8. This is more advantageous than the stairwell smoke prevention system (201010580513.6) which can only block smoke. Because the stairwell smoke prevention system (201010580513.6) cannot form a positive pressure zone at all, see Figure 9. Therefore, this application has a better barrier to smoke, and the smoke concentration in the protected area is lower. As shown in Figure 10, the original system "stairwell smoke prevention system (201010580513.6)" with the lapse of ignition time, due to the increase of smoke turbulence, more smoke enters the smoke prevention area, and the smoke concentration gradually increases. time to increase. However, this patent has no influence in this regard. As the ignition time elapses, the smoke concentration in the smoke prevention area is maintained at a constant value, which is obviously lower than that of the original system. This shows that the positive pressure zone and the jet flow zone respectively formed by the gradually expanding blowing port and the common blowing port in this patent are more advantageous than the existing common blowing port, and have a greater resistance to smoke.

2. From the point of view of the manufacturing price, since the number of the nozzles of the present invention is only 4 and the original system has 6 nozzles, the air volume of the present invention is 30% less than that of the original system under the same conditions. At the same time, due to the saving of air volume, the fan can also be changed from the original large model to the current small model fan. In this way, the initial construction investment of the overall system will be reduced by more than 20%. In terms of operating efficiency. And because the air volume requirement is smaller, the efficiency during operation is higher, and the power consumption during system operation is relatively reduced.

Claims (2)

1. a building element safe evacuation system for airflow closed channel in middle, comprise the first plenum chamber (1) and the second plenum chamber (8), described the first plenum chamber (1) and the second plenum chamber (8) symmetrical parallel setting, between the first plenum chamber (1) and the second plenum chamber (8), by ventilation shaft (9), be connected, ventilation shaft (9) is connected with blower fan (10);

It is characterized in that: described the first plenum chamber (1) lower end is provided with the first spout (2), the second spout (3) and the 3rd spout (4), and wherein the first spout (2) and the 3rd spout (4) lay respectively at the second spout (3) both sides; Be provided with the 4th spout (5), the 5th spout (6) and the 6th spout (7) in the second plenum chamber (8) upper end, wherein the 4th spout (5), the 6th spout (7) lay respectively at the 5th spout (6) both sides;

Described the first spout (2), the second spout (3) and the 3rd spout (4) are symmetrical arranged with the 4th spout (5), the 5th spout (6) and the 6th spout (7) along continuous straight runs respectively, and the second spout (3) is relative towards vertically with the 5th spout (6) air-out, the air-out of the first spout (2) and the 4th spout (5) is towards intersecting, and the 3rd spout (4) and the 6th spout (7) air-out are towards intersecting;

Described the second spout (3) and the 5th spout (6) are vertically blown, the first spout (2) and the 4th spout (5) are 1 °～5 ° with the vertical direction angle, the 3rd spout (4) is 1 °～5 ° with the 6th spout (7) with the vertical direction angle, and the first spout (2) and the 4th spout (5), the 4th spout (5) also vertically is symmetrical arranged respectively with the 6th spout (7).

2. building element safe evacuation system for airflow closed channel in middle as claimed in claim 1, it is characterized in that: described the second spout (3) and the 5th spout (6) they are flaring type spout, and the Area Ratio of flaring type spout exit and porch is 5:1; The exit of the second spout (3) and the 5th spout (6) is 5:1 with the exit Area Ratio of the first spout (2), the 3rd spout (4) and the 4th spout (5), the 6th spout (7) respectively; Fore-and-aft distance between the second spout (3) and the 5th spout (6) exit is less than 3m; Distance between the second spout (3) and the 4th spout (6) is less than 3m.

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