106 results about "Air well" patented technology

A mine cooling and dehumidifying system includes a compressor, a gas-liquid separator, an evaporator, a condenser and an expansion valve. The evaporator is in an air supply well, and the condenser is in a return air well; the compressor, the gas-liquid separator and the expansion valve are all between the air supply well and the return air well; an inlet of the compressor is connected to a refrigerant outlet of the evaporator through the gas-liquid separator, and a refrigerant inlet of the evaporator is connected with an outlet of the expansion valve; an inlet of the expansion valve is connected with a refrigerant outlet of the condenser, and a refrigerant inlet of the condenser is connected with an outlet of the compressor. In the present disclosure, by vapor compression type refrigeration cycle, the downhole air heat is transferred to the return air and then discharged to the ground.

The invention provides a novel coal mining method for an open-air well-to-well worker. The novel coal mining method comprises the following steps: stoping by a slope coal mining machine; filling a mining cave, determining a filling process, selecting one of pumping filling, waste rock throwing machine filling or side upper part drill hole conveying filling in the filling process, and selecting filling materials according to a ratio of waste rock to concrete; carrying out slope stability calculation and analysis and slope monitoring, and carrying out mechanical analysis and calculation by adopting a limit equilibrium method and a finite element method. The invention provides a mining process system and complete equipment, including automation of coal mining and transportation, realization of automatic operation and connection of coal, mining and transportation equipment, improvement of coal mining efficiency and efficiency of a filling system, and realization of key technologies and processes of efficient paste filling, and provides an overlying strata stability monitoring control technology and equipment. The intelligent mining site is realized, the scientific and reasonable cooperation of mining, filling and slope stability monitoring is realized, and the connection is orderly and efficient.

The utility model discloses a mechanical pressurized air supply structure for an antechamber of a building, comprising an air inlet pipe, a pressurized air supply fan, an electric regulating valve, a 70°C fire damper, an electric normally closed valve, a pressurized air supply port, a residual pressure sensor, an air supply main pipe and an air supply branch pipe, wherein the air inlet pipe and the pressurized air supply fan are arranged in a special fan room, and the air supply main pipe is laid in a civil engineering air shaft; the air supply branch pipe passes through a partition wall of the civil engineering air shaft and is laid on the top of an upturned beam bottom of an antechamber, the air supply branch pipe is connected with the air supply main pipe, the air inlet pipe is connected with the pressurized air supply fan, the pressurized air supply fan is connected with the air supply main pipe through the electric regulating valve and the 70°C fire damper in sequence, and the air supply branch pipe entering the antechamber of each floor is provided with an electric normally closed valve and a pressurized air supply port. The utility model arranges an upturned beam at the partition wall of the civil construction air shaft so that the top of the pressurized air supply branch pipe is close to the upturned beam and the bottom is almost level with the bottom of the top plate of the front room, and is laid to connect to the front room. The air duct occupies a small net height of the front room, and at the same time, a suspended ceiling decoration is adopted to eliminate the influence of the air supply branch pipe extending into the front room on the visual impact of the front room.

The utility model relates to a skid-mounted gas well mouth desanding device which comprises a rotational flow gravity desander, a gas well mouth desanding device, a gas well mouth desanding device, a gas well mouth desanding device, a gas well mouth desanding device, a gas well mouth desanding device, a gas well mouth desanding device and a gas well mouth desanding device, the multiple filtering type sand removers are arranged in parallel, inlets of the multiple filtering type sand removers are all connected with an outlet of the rotational flow gravity sand remover, and outlets of the filtering type sand removers are used for discharging filtered natural gas; and each filter type sand remover is provided with a drain outlet and a backwashing opening. The throttling valve and the safety shut-off valve can ensure that a gas mixture from a gas well flows into the rotational flow gravity desander after meeting the pressure condition; the cyclone gravity desander is used for carrying out gas-liquid-solid separation on the entered gas mixture; the filter type desander is used for further separating the gas mixture, and the filtered natural gas is discharged from an outlet of the filter type desander.

The invention discloses a natural ventilation and mechanical ventilation interconvertible road tunnel ventilation system, which is arranged in a one-way driving road tunnel and comprises a tunnel road natural ventilation facility and a tunnel road mechanical ventilation facility, the tunnel road natural ventilation facility comprises a natural ventilation duct, a natural ventilation shaft and a natural ventilation valve; the tunnel road mechanical ventilation facility comprises a mechanical ventilation duct, a mechanical ventilation shaft, a mechanical ventilation valve and a ventilator. A natural ventilation opening of the one-way driving road tunnel is sequentially connected with a natural ventilation valve and a natural ventilation shaft through an air duct. The natural ventilation duct between the natural ventilation valve and the natural ventilation opening is sequentially connected with a tunnel mechanical ventilation valve, a ventilator and a mechanical ventilation shaft through a tee joint; the road tunnel mechanical ventilation valve and the ventilator are in a chain opening and closing relation. The invention provides a tunnel ventilation system which not only can meet the tunnel ventilation requirement, but also can solve the problems of land acquisition, landscape, environment and the like.

The present invention discloses a method for developing a condensate gas reservoir. The method comprises: adopting a development method adapted to different production stages of the condensate gas reservoir, carrying out exhaustion development in the early stage of the condensate gas reservoir development until the condensate gas reservoir reaches the set exhaustion development lower limit; switching to air injection development, selecting at least one production well from the condensate gas reservoir according to a set rule, changing the selected production well into an air injection well, and injecting a catalyst and a combustion aid into the air injection well; determining the air injection rate according to the effective oil layer parameters of the condensate gas reservoir, and injecting air into the air injection well according to the determined air injection rate. The condensate gas reservoir can be effectively developed in the full cycle development process, thereby improving the development efficiency and recovery rate.

The embodiment of the invention provides a gas well annulus detection method and device and a storage medium, and the method comprises the steps: obtaining the annulus pressure of a to-be-detected gas well, and determining an annulus pressure curve according to the annulus pressure; the annulus pressure curve is substituted into an annulus pressure curve prediction model, whether the gas well to be detected leaks or not is determined, if the gas well to be detected leaks, basic parameters of the gas well to be detected are obtained, the basic parameters are substituted into an annulus leakage prediction model, and leakage point parameters of the gas well to be detected are determined. The method can accurately detect the gas well annulus leakage point.

The invention relates to the technical field of working condition diagnosis and early warning. The gas well working condition diagnostic analysis method based on the real-time production data comprises the steps that actual characteristic production data of all collection point positions are obtained and integrated to obtain an actual gas well production data set, the actual gas well production data set is preprocessed, and a target gas well production data set is obtained; performing feature screening on each actual feature production data in the target gas well production data set to obtain a plurality of target feature production data, and integrating each target feature production data to obtain a target gas well production data string; and performing last-stage processing on the target gas well production data string, dividing the target gas well production data string according to a last-stage processing result, and performing gas well production data training, testing and verification on the target gas well production data string in sequence to establish a target algorithm model. The method can realize early discovery and timely treatment of the abnormal working condition of the gas well, and lays a foundation for reasonably planning field production resources and improving natural gas yield.

The invention relates to the technical field of coal mines, in particular to a coal mine air shaft carbon dioxide recycling and sealing device and a sealing method thereof.The coal mine air shaft carbon dioxide recycling and sealing device comprises an air pump and a first conveying pipe, a recycling cover is fixedly installed at one end of the first conveying pipe, and a dust removal box is installed on one side of the air pump; a sealing tank is arranged on one side of the dust removal box, a compressor connected with the dust removal box is fixedly installed on one side of the sealing tank, a condenser connected with the sealing tank is fixedly installed on the top of the compressor, and a fixing structure is arranged on the recovery cover. Through the arrangement of the fixing structure, the recycling cover can be fixed to the air shaft opening, the first screw rod is rotated to drive the fastening plates to move in the first fixing frame, the two fastening plates get close to each other to clamp the air shaft opening so as to fix the recycling cover, and the situation that in the recycling process, the recycling cover shakes on the air shaft opening to generate a gap is avoided; and pollution and waste caused by leakage of carbon dioxide from gaps are effectively prevented.

The utility model discloses a wind tower internal part capable of adjusting an air outlet angle, and relates to the field of ventilation shaft shutter air outlets. The window comprises the window frame, the window frame comprises the first frame, the second frame, the top frame and the bottom frame, the abutting mechanism is installed on the window frame, through the abutting mechanism and a screwing bolt, by means of the threaded connection characteristic of the screwing bolt and the abutting block, firstly, accurate position adjustment of the abutting block in a cavity can be achieved, and the abutting block can be tightly screwed along with gradual screwing of the bolt. The abutting block stably moves outwards in the cavity under the thrust action of the threads until the surface of the abutting block tightly abuts against the inner wall of the installation groove, it is guaranteed that the initial position between the window frame and the installation groove is fixed in the process, the assembly gap between the window frame and the installation groove is effectively reduced, and meanwhile the assembly efficiency is improved. Stable supporting points are provided for the air outlet shutters through firm abutting of the abutting blocks, and the stability and firmness of the whole installation structure are remarkably improved.

The invention discloses a prefabricated cabin ventilation system, which relates to the technical field of prefabricated cabins, and comprises a centralized ventilation room and a prefabricated cabin, the centralized ventilation room is provided with a ventilation shutter, and the ventilation shutter is provided with a coarse filtering piece; the centralized ventilation room is connected with the foundation through a ventilation room foundation, a ventilation shaft is arranged in the ventilation room foundation, and the ventilation shaft is communicated with the centralized ventilation room; the prefabricated cabin is connected with a foundation through a prefabricated cabin foundation, a precise filtering piece is arranged between the prefabricated cabin and the prefabricated cabin foundation, and the prefabricated cabin is provided with an air outlet assembly; an inner cavity of the prefabricated cabin foundation is communicated with the ventilating shaft through a transverse ventilating shaft, and a medium-efficiency filtering piece is arranged between the transverse ventilating shaft and the ventilating shaft; the transverse ventilation shaft is provided with a water spray dust suppression mechanism and a dust particle detector, the dust particle detector is used for detecting the amount of sand and dust in the transverse ventilation shaft, and the water spray dust suppression mechanism is used for suppressing the sand and dust in the transverse ventilation shaft. Based on the scheme, the ventilation and sand prevention effects of the prefabricated cabin are improved.

A mine cooling and dehumidifying system includes a compressor, a gas-liquid separator, an evaporator, a condenser and an expansion valve. The evaporator is in an air supply well, and the condenser is in a return air well; the compressor, the gas-liquid separator and the expansion valve are all between the air supply well and the return air well; an inlet of the compressor is connected to a refrigerant outlet of the evaporator through the gas-liquid separator, and a refrigerant inlet of the evaporator is connected with an outlet of the expansion valve; an inlet of the expansion valve is connected with a refrigerant outlet of the condenser, and a refrigerant inlet of the condenser is connected with an outlet of the compressor. In the present disclosure, by vapor compression type refrigeration cycle, the downhole air heat is transferred to the return air and then discharged to the ground.

An underground fire-fighting sound noise control ventilation device relates to the field of ventilation equipment and comprises a ventilation shaft, a rain shelter is arranged at the top of the ventilation shaft, a plurality of ventilation ports are formed in the upper side of the ventilation shaft, steel wire meshes are arranged on the ventilation ports, an upper noise elimination mechanism and a lower noise elimination mechanism are arranged in the ventilation shaft, a ventilation pipe is arranged on one side of the ventilation shaft, and the ventilation shaft is provided with a ventilation hole. A filtering mechanism is inserted in the ventilation pipe, the upper noise elimination mechanism and the lower noise elimination mechanism are arranged in a staggered mode, the rain shelter effectively prevents rainwater and sundries from invading, and normal operation of equipment is guaranteed; the ventilation port is combined with the steel wire mesh, ventilation is guaranteed, and foreign matter is prevented from entering; the double-silencing mechanism remarkably reduces operation noise, and the use experience is improved; the fan and the exhaust fan enhance the active ventilation capability and improve the ventilation efficiency; and the filtering mechanism further ensures the air quality.

1. The name of the design product: roof rig (four oil cylinders and two vertical columns). 2. The use of the design product: used for the construction of ventilation shaft, chute shaft, cable and water pipe arrangement shaft in underground mine. 3. The design points of the design product: in shape. 4. The picture or photo that best shows the design points: perspective view 1.

The invention discloses an energy-saving air conditioning system for a building. The energy-saving air conditioning system comprises a ventilation shaft, a tunnel air pipe, a TLambert wall, a sky radiation layer and a heat storage layer. The heat storage layer is arranged at the top of the ventilation shaft; the TLambert wall is arranged on the sunny side of the ventilation shaft and is relatively close to the top of the ventilation shaft; the sky radiation layer is arranged on the shady side of the ventilation shaft and is relatively close to the bottom of the ventilation shaft; the tunnel air pipe is used for being communicated with or disconnected from the bottom of the ventilation shaft so that temperature difference can be formed in the ventilation shaft and air can be driven to flow from bottom to top. A condensation face is arranged in the ventilation shaft, and the condensation face is located on an air flowing path and used for dehumidifying air. A coupled passive cooling and dehumidifying building energy-saving air conditioning system is formed by tunnel air, sky radiation, a Tembert wall, phase change heat storage and a condensing surface, and the cooling and dehumidifying effects can be achieved by completely depending on renewable low-grade natural energy without mechanical driving such as a fan or a compressor.

The invention belongs to the technical field of receiving wells, and particularly relates to a fusiform receiving well which comprises a receiving well body, a bottom plate is arranged at the bottom of the receiving well body, the receiving well body is communicated with a jacking pipe through a jacking pipe inserting hole formed in the side face of the receiving well body, a supporting plate is arranged in the receiving well body, a climbing assembly is arranged on the supporting plate, and the appearance of the receiving well body is of a fusiform structure. The upper cover component is arranged at the upper end of the receiving well body, the receiving well body is of a fusiform structure and is good in streamline, the water blocking ratio is 3%, the requirement that the water blocking ratio is not larger than 15% is met, in addition, the receiving well body can serve as a ventilation well, the upper cover component is arranged on an upper opening of the receiving well body, and rainwater, floating objects and the like are prevented from falling into the receiving well body. The interior of the receiving well body is kept clean and relatively dry.

The utility model discloses a local ventilation device for a coal mine, and relates to the technical field of coal mining. The device comprises a bearing plate which is arranged at an inlet or a ventilation wellhead of a mine, a placing groove is fixedly formed in one side of the bearing plate, a supporting plate is fixedly arranged on one side of the placing groove, a control panel is installed on the top of the supporting plate, and a power regulator is arranged on the upper side of the front face of the supporting plate; and the ventilation mechanism is used for extracting air from the mine and conveying external air into the mine, and the ventilation mechanism comprises an air blower installed on the other side of the top of the bearing plate. The gas concentration sensor can monitor the gas concentration in a mine in real time, and when the gas concentration exceeds a set threshold value, the control panel can automatically adjust the power of the air blower through the power regulator, so that the operation power of the ventilation mechanism is changed, the air volume is rapidly increased, the ventilation efficiency is improved, and the safety of miners is guaranteed.

The utility model belongs to the technical field of anti-explosion well lids, and discloses a mining ventilation well anti-explosion well lid which comprises a ventilation well, an anti-explosion well lid body is installed at the upper end of the ventilation well, pull blocks are installed on the front face and the back face of the upper end of the anti-explosion well lid body, and a controller is arranged on the lower right portion of the upper end of the ventilation well. A water tank is arranged in the center of the upper end of the ventilation shaft, a conveying pump is arranged at the upper end of the water tank, a connecting pipe is installed at the upper end of the conveying pump, a closed ring is installed at the lower end of the water tank, and first sliding rods are installed on the two sides of the lower end of the closed ring; the explosion-proof well lid has the advantages that when the surface temperature of the water tank is too low or too high, the water tank can be automatically heated and cooled, the functionality of the explosion-proof well lid of the mining ventilation shaft is improved, the explosion-proof well lid of the mining ventilation shaft can have the buffering and damping functions when the interior explodes, and the explosion-proof well lid of the mining ventilation shaft is convenient to use. And the service life of the anti-explosion well lid is prolonged.

The application discloses a kind of ventilation parameter processing method and system for the whole world water-rich karst tunnel small section multi-shaft, comprising the following steps: determining small section shaft clearance diameter D And single well ventilation capacity, and determine the upper limit of main hole design wind speed to obtain the maximum wind capacity of main hole;Select control need air volume index, calculate the air volume and establish relative index, determine the critical distance L 1 when relative index reaches limit value L First exhaust shaft is arranged near L 1 And downstream air supply shaft constitutes "one exhaust one supply" ventilation unit, according to different section relative index check and iterative arrangement of multiple groups of shafts form shaft group, so that downstream available air volume meets the next partition air volume.The application replaces the traditional large-diameter ventilation shaft by adopting small-section shaft group suitable for mechanized construction, which can reduce the construction risk of shaft in the whole water-rich karst section, reduce the exposure of underground personnel, and improve the engineering applicability and construction safety.

The invention provides a fresh air system for a smart building. The fresh air system for the intelligent building comprises a basement; a ventilation shaft; a filtering mechanism; a rubber pad is in sliding connection with a fixing strip, a partition plate, an activated carbon layer and a fiber filter screen; the interior of the first barrel and the interior of the second barrel are slidably connected with the piston, and the side wall of the piston is fixedly connected with the supporting rod; a pulling mechanism; the multiple one-way valves are mounted on the side walls of the first barrel, the second connecting pipe and the third connecting pipe correspondingly; the dehumidification mechanism is fixed at the bottom end of the ventilation shaft; and the driving mechanism is connected with the dehumidification mechanism, the ventilation shaft and the hose. The fresh air system for the intelligent building has the advantages that the primary filter screen is cleaned in time, fresh air is stably and continuously input, and the filter screen is convenient to clean.

The bullet plunger belongs to the technical field of gas well equipment, and in particular to a bullet plunger. The present invention provides a bullet plunger with good use effect. The bullet plunger 100 of the present invention includes a plunger shaft 110-2, characterized in that a spring 110-5 is arranged on the outer wall of the plunger shaft 110-2, a spring 110-4 is arranged between the inner wall of the spring 110-5 and the outer wall of the plunger shaft 110-2, the inner end of the spring 110-4 is against the outer wall of the plunger shaft 110-2, and the outer end of the spring 110-4 is against the inner wall of the spring 110-5.

The present invention discloses an embedded gas stove, comprising a bottom shell and a burner, wherein the bottom shell comprises a panel and a side panel arranged around the panel, the burner is fixed on the panel, and the burner is connected to an ejector pipe for conveying gas, and an air supply device for supplying air to an ejector port of the ejector pipe is also provided on the panel, so that the gas and air are fully premixed. The embedded gas stove of the present invention improves the primary air coefficient of the gas stove burner, effectively improves the thermal efficiency of the gas stove, and reduces the emission of harmful gases. The bottom shell is designed as an open structure with adjustable size, which is conducive to the air entering the bottom shell, ensuring that the air volume in the bottom shell is sufficient, and the blower is conducive to improving the primary air coefficient, so that the gas and air are better premixed.

A ventilation system for an underground tunnel pumped storage space includes a working shaft and a ventilation shaft that directly lead to the underground tunnel space. The working shaft and the ventilation shaft are interconnected, forming an inlet and outlet for the air to circulate in the underground tunnel. The underground space is divided into a water-filled space and a non-water-filled space by a waterproof gate wall. Both spaces are connected to the main ventilation channel formed by the working shaft and the ventilation shaft. In order to meet the different ventilation needs of the two separated underground spaces, the present invention proposes a ventilation system that meets the needs of the underground water-filled space and the non-water-filled space. The present invention sets different ventilation processes based on the layout differences and functions of the underground tunnel space to meet the ventilation and air exchange needs of each stage of operation and shutdown and maintenance, realize the physical isolation of the dangerous gas accumulation space and the equipment operation space, ensure the safety of the equipment and personnel areas, greatly reduce the explosion-proof performance requirements of the area for the equipment, reduce the one-time investment cost, and at the same time reduce the space for forced ventilation and reduce energy consumption during operation.

The invention discloses a pump-drive-free super-long gravity assisted heat pipe type refrigerating system applied to a deep mine, and belongs to the technical field of mine heat management and energy conservation. The system comprises a super-long gravity heat pipe, an air cooler, a condensation evaporator, a surface air cooler and related pipelines. The super-long gravity heat pipe extends to a mine tunneling layer, underground heat is absorbed through the air cooler, a working medium is evaporated into steam in the heat pipe and naturally ascends to the condensation evaporator, and the heat is transmitted to the working medium of the heat pump at the position. And the liquid working medium is further condensed by the surface air cooler and enters circulation. The system uses gravity and steam pressure difference to drive the heat pipe working medium to circulate, a pump does not need to serve as a power source, underground equipment is simplified, and energy consumption is reduced. Meanwhile, the system can be flexibly arranged in a ventilation shaft or other proper positions according to the actual situation of the mine. The system is simple in structure, reliable in operation, energy-saving and efficient, and meets the requirements of efficient cooling and heat management of deep mines.

The present application relates to the technical field of gravel filling well completion in drilling engineering, and particularly relates to a self-driven rotary annular gravel throwing device and a synchronous well washing method, which comprises a moving platform, a gravel storage hopper integrated on the moving platform, a slurry pump, a water gravel pipe, an annular gravel thrower, a self-driven rotary conical blocking cap, a slurry suction pipe, a slurry suction pump, a mud purification device and an air compressor; a hoisting arm is arranged at the front end of the moving platform, a hoisting cable is arranged at the front end of the hoisting arm, the lower end of the hoisting cable is connected with the slurry suction pump and the slurry suction pipe, and the hoisting cable can be telescoped up and down to drive the slurry suction pump and the slurry suction pipe to move up and down in the well wall pipe, and the method comprises S1, installation and early preparation of the self-driven rotary annular gravel throwing device; S2, self-driven rotary annular gravel throwing; S3, air well washing; and S4, continuous mud purification, and the self-driven rotary uniform gravel throwing and water flow guidance compaction do not need additional power.

The invention provides a target gas storage single well productivity prediction method and device, and the method comprises the steps: obtaining the single well productivity test well production data of a target gas storage, and obtaining the average gas injection and production amount of a production stage; calculating the flowing bottomhole pressure of the gas well corresponding to each production data point by utilizing preset gas component analysis data, oil pipe parameters and a preset wellbore pipe flow equation; and calculating the average gas well open-flow capacity in the injection-production stage by using the average formation pressure in the current time period, the gas production well daily gas production rate of each production data point, the gas well bottom hole flow pressure and a preset one-point method open-flow capacity formula. On the basis of the injection-production two-way process, an open-flow capacity formula for the gas storage is established; and combining the exponential open-flow capacity equation set and the exponential productivity equation set to obtain an exponential productivity equation of a single well to predict the productivity of the single well of the target gas storage. According to the method, derivation of the single-well productivity equation is simplified, the single-well productivity equation is accurately derived with fewer production data points, and single-well productivity prediction can be rapidly implemented.

The utility model discloses a safe civil air defense ventilation device which is convenient for maintenance and relates to the technical field of civil air defense ventilation devices. The utility model comprises a box body, an air inlet mechanism is arranged inside the box body, the air inlet mechanism is used to bring outside air into the device, a filtering mechanism used in conjunction with the air inlet mechanism is arranged inside the box body, the filtering mechanism is used to filter outside air, the air inlet mechanism comprises an air inlet frame, rotating frames are fixedly arranged on both sides of the air inlet frame, a motor is arranged on one side of one of the rotating frames, a rotating rod is fixedly arranged on the output end of the motor, and a fan impeller is fixedly arranged on the outer surface of the rotating rod. The utility model can transport outside air into the device in large quantities and continuously through the air inlet mechanism, thereby realizing that the safe civil air defense ventilation device can well allow air to enter the device, and through the filtering mechanism, the safe civil air defense ventilation device can well filter the air.

The utility model discloses a pump-drive-free super-long gravity assisted heat pipe type refrigerating system applied to a deep mine, and belongs to the technical field of mine heat management and energy conservation. The system comprises a super-long gravity heat pipe, an air cooler, a condensation evaporator, a surface air cooler and related pipelines. The super-long gravity heat pipe extends to a mine tunneling layer, underground heat is absorbed through the air cooler, a working medium is evaporated into steam in the heat pipe and naturally ascends to the condensation evaporator, and the heat is transmitted to the working medium of the heat pump at the position. And the liquid working medium is further condensed by the surface air cooler and enters circulation. The system utilizes gravity and steam pressure difference to drive working medium circulation, does not need a pump as a power source, simplifies underground equipment and reduces energy consumption. Meanwhile, the system can be flexibly arranged in a ventilation shaft or other proper positions according to the actual situation of the mine. The system is simple in structure, reliable in operation, energy-saving and efficient, and meets the requirements of efficient cooling and heat management of deep mines.

A passive flood barrier that self-deploys to prevent or limit the passage of flood water through an opening in a structure such as a ventilation shaft. The passive flood barrier device includes a buoyant volume extending across at least a portion of the structural opening. The buoyant volume is configured to float in response to flood water near the structural opening. A flexible flood barrier is coupled to the buoyant volume. The flexible flood barrier is deployable from the buoyant volume as the buoyant volume travels upward in response to flood water near the structural opening.