211results about How to "Low flow resistance" patented technology

The invention relates to a gas nano purifier. The gas nano purifier comprises a mounting seat, the gas storage bin is installed on the installation base and used for storing clean gas, the side wall of the upper portion of the gas storage bin extends upwards to form an installation plate, and a gas path through hole is formed in the middle of the installation plate; the gas-water separator is mounted on the mounting plate and is used for carrying out primary purification on to-be-cleaned gas; the adsorption tower is mounted on the mounting plate and is used for carrying out secondary purification on the to-be-cleaned gas; gas to be cleaned sequentially flows through the gas-water separator and the adsorption tower and then enters the gas storage bin; the adsorption tower is communicated with the gas storage bin through an exhaust pipe; and the exhaust pipe penetrates through the gas path through hole. Through the arrangement, the installation operation is greatly simplified, and the integrity and the space utilization rate of equipment are improved.

The invention relates to an epoxy resin pouring type transformer with built-in microcirculation cooling channels and a heat dissipation method of the epoxy resin pouring type transformer, and belongs to the technical field of power transformers. The epoxy resin pouring type transformer comprises an iron core, a low-voltage winding, a high-voltage winding and a heat dissipation shell, the low-voltage winding and the high-voltage winding are completely impregnated and wrapped by an epoxy resin composite material through a vacuum pouring process, an integrated epoxy resin pouring body is formed after curing, and a three-dimensional communicated bionic microcirculation cooling channel network is arranged in the epoxy resin pouring body; the heat dissipation shell is in close contact with the outer surface of the epoxy resin pouring body through the high-heat-conductivity insulating medium. According to the invention, the heat dissipation efficiency can be remarkably improved, and a cooling medium (air) is directly guided to a microscopic area around the winding conductor through a three-dimensional communicated and tree-shaped fractal bionic microcirculation cooling channel network, so that the effective heat exchange area and the heat exchange strength are greatly increased, and internal heat can be accurately and efficiently taken away.

The utility model relates to a kind of cleaning machine ventilation structure, belong to cleaning equipment technical field.A kind of cleaning machine ventilation structure, including cover body assembly;Baffle assembly, the baffle assembly is set on the cover body assembly, the baffle assembly and the cover body assembly cooperation form mounting groove, the cover body assembly is equipped with the first air outlet with the installation groove intercommunication, the first air outlet is located in the side portion of the baffle assembly;Ventilation component, the ventilation component can be detachably installed on the cover body assembly or the baffle assembly and at least part is located in the installation groove, the ventilation component is equipped with the ventilation hole with the first air outlet intercommunication.Ventilation component can be detachably installed, it is easy to clean up and replace damaged part that block ventilation hole, reduce maintenance cost and downtime.Cover body assembly, the mounting groove formed by baffle assembly and ventilation component are adapted, cooperate buckle, limiting structure, can resist airflow impact, prevent ventilation component from being washed out, guarantee ventilation function stability.

This invention relates to a method for extracting natural gas hydrates and the perfluorocarbon extractant used therein. The perfluorocarbon extractant comprises a viscosity modifier, an interface modifier, and a solvent; the viscosity modifier includes perfluorotributylamine; and the interface modifier includes perfluoropolyether and / or perfluorobutyric acid. The perfluorocarbon extractant of this invention exhibits high solubility for methane, strong hydrophobic properties, and stable physicochemical properties. During natural gas hydrate extraction, it allows methane released after hydrate decomposition to preferentially enter the extractant phase in a dissolved state and migrate within the reservoir, thereby achieving single-phase liquid extraction of methane. This technical approach can weaken or even eliminate the Jamin effect and seepage blockage caused by gas-liquid two-phase mixing, reduce reservoir flow resistance, and improve the extraction efficiency and continuous gas production capacity of natural gas hydrates in silty clay reservoirs.

The invention discloses a micromotor-driven distributed turbulent flow pumpless liquid cooling device for space thermal control. The micromotor-driven distributed turbulent flow pumpless liquid cooling device comprises a pipeline body and an impeller pump, the impeller pump comprises an impeller with the outer diameter being D and capable of actively rotating. When the impeller pump is used for overall heat dissipation of a single small-size electronic element, one impeller pump is arranged in the cooling flow channel at the position 0.5 D-1. 5D away from the upstream of the small-size electronic element; when the impeller pump is used for eliminating the hot spots of the large-size electronic element, one impeller pump is arranged in the cooling flow channel at the position 0.5 D-1. 5D away from the upstream of each hot spot to be eliminated. An external pump is removed, and the impeller pump is arranged in the cooling flow channel, so that on one hand, a cooling working medium is pumped, on the other hand, a turbulent flow effect is achieved on the cooling working medium, a boundary layer is broken, and the heat dissipation effect is improved. In addition, for a large-scale heat dissipation scene, a plurality of impeller pumps can be arranged in the cooling flow channel in an array mode, the impeller pumps can be placed at local hot spots in a targeted mode, targeted heat dissipation is achieved, and the heat dissipation efficiency and uniformity are further improved.

The application discloses a kind of pneumatic directional drilling system and drilling method suitable for local water-containing soft coal seam, including directional drill bit, screw drill, conversion nipple, non-magnetic drill tool, multiple special directional drill pipes and air feeder connected in order from back to front;The screw drill includes output shaft end head connected with the directional drill bit and stator end head sleeved on one side of output shaft end head, and output shaft end head can rotate relative to the stator end head, by setting screw drill and conversion nipple, both directional drilling in water-containing soft coal seam can be guaranteed, and strong blowing process can be implemented to discharge drill cuttings and formation water in hole to outside of hole in time, keep drilling operation continuous and smooth, greatly reduce the amount of operation of pulling down drill during construction, and the comprehensive drilling efficiency can be improved by more than 20%, solve the technical problems of poor formation adaptability of prior art, and cannot realize strong blowing and cuttings discharge and rapid switching of directional drilling during directional hole construction process in local water-containing soft coal seam, resulting in low drilling efficiency.

This utility model discloses a split-type GIL busbar housing, which relates to the field of power engineering technology. The split-type GIL busbar housing includes an end cover and a busbar unit. The outer wall of the end cover is fixedly connected to the inner wall of the busbar unit. The busbar unit includes a unit shell, which constitutes the main structure of the busbar unit. An air filter is fixedly connected to the inner wall of the unit shell. The air filter effectively filters dust and other impurities from the outside air, preventing them from entering the busbar unit. A male connector is fixedly connected to one end of the inner wall of the unit shell, and a female connector is fixedly connected to the other end. Through the cooperation of the male and female connectors, rapid connection and separation between multiple busbar units can be achieved.

The utility model discloses a liquid cooling plate which comprises an upper cover plate and a lower cover plate, and a main flow channel is formed between the upper cover plate and the lower cover plate; the water inlet nozzle is communicated with the water inlet of the main flow channel and is used for allowing a refrigerant to flow in; the water outlet nozzle is communicated with a water outlet, corresponding to the water inlet, of the main runner and is used for allowing a refrigerant to flow out; the heat exchange columns are arranged in the main flow channel, and the densities of the heat exchange columns in different areas in the main flow channel are different. According to the liquid cooling plate, the plurality of heat exchange columns are arranged, so that the structural strength of the liquid cooling plate can be enhanced, the contact area between a refrigerant and the flow channel wall can be increased, and the heat exchange efficiency is improved. Besides, the heat exchange columns with different densities are arranged in different areas, so that the flow distribution of the refrigerant in the flow channel can be optimized, the refrigerant is uniformly distributed, and the uniformity of the heat dissipation performance of the liquid cooling plate is improved.

The utility model provides an air purifier which comprises a shell provided with an airflow channel, and the airflow channel penetrates through the two opposite sides of the shell; the condensation filter screen is arranged at the air inlet end of the airflow channel and is used for uniformly distributing and condensing the inlet airflow; the composite filter element is arranged in the airflow channel, located between the air inlet end and the air outlet end of the airflow channel and used for filtering liquid pollutants, aerosol particles and gas pollutants in the condensed airflow; the fan is arranged at the air outlet end of the airflow channel, and the fan is used for guiding airflow to flow in from the air inlet end of the airflow channel and to be discharged from the air outlet end of the airflow channel; wherein the airflow channel is linear. According to the air purifier, the airflow backflow probability can be effectively reduced, the turbulent flow energy generation rate is greatly reduced, and airflow flows more smoothly in the airflow channel, so that airflow around the air purifier smoothly flows into the airflow channel, the smoke escape amount can be effectively reduced, and the oil smoke purification efficiency is improved.

The present application relates to a kind of chair armrest side plate injection mold hot runner glue feeding control method and its mold, it relates to injection mold technical field, it includes: in response to the mold completion signal, product information, cavity information and glue feeding position are collected;According to cavity information, determine flow rate threshold, glue feeding duration and the glue feeding component corresponding to glue feeding position;Determine glue feeding flow rate by combining product information, glue feeding component and glue feeding duration;The glue feeding position corresponding to the glue feeding flow rate greater than flow rate threshold is defined as exceeding position, and the glue feeding position adjacent to exceeding position is defined as adjacent position;Adjacent relationship of exceeding position is obtained;Based on adjacent relationship, glue feeding flow rate is corrected;The operating unit is controlled to run by combining corrected glue feeding flow rate and glue feeding duration.The present application has the effect of avoiding product to appear weld mark obvious, local shrinkage mark and other quality defects.

The utility model relates to the technical field of clothes treatment, in particular to a clothes treatment device and combined clothes treatment equipment. By arranging the adapter, the first air port and the second air port are respectively communicated with the corresponding cylinder bodies, so that the first water outlet and the second water outlet are respectively consistent with the internal air pressure of the corresponding cylinder bodies, and the two washing cavities can operate simultaneously or independently; the siphonage phenomenon of the two drainage pipes which are draining water due to the fact that internal air is emptied is avoided, and the problem of sewage reverse flow caused by the siphonage phenomenon is prevented. In addition, the first drainage pipe, the second drainage pipe, the first air pipe and the second air pipe can be conveniently connected, supported and positioned through the adapters, the layout of the drainage assembly is more compact through the adapters, the pipeline length is reduced, the water flow resistance is reduced, and the drainage efficiency is improved.

The utility model discloses a liquid cooling row and CPU liquid cooling heat abstractor, the liquid cooling row includes liquid inlet cavity, exchange cavity, liquid outlet cavity, a plurality of radiators, liquid inlet connector and liquid outlet connector, and the liquid inlet connector and liquid outlet connector are all corner connectors of 90 degree corner, and the CPU liquid cooling heat abstractor including this liquid cooling row still includes fan, liquid inlet pipe, liquid outlet pipe and liquid cooling head, and it sets up parallelly liquid outlet connector and fan, and the CPU liquid cooling heat abstractor sets up the side of liquid inlet pipe and liquid outlet pipe parallel to the liquid cooling row, under the condition of high -efficient utilization limited space, makes the case inside appearance sense remarkable promotion to reduce the bending of liquid inlet pipe and liquid outlet pipe, reduces the risk of liquid leakage, and can guarantee the heat dissipation effect.

The invention discloses a carbon dioxide inter-section displacement pre-fracturing process and a design method and related equipment thereof, and belongs to the technical field of oil and gas production, the design method comprises the following steps: establishing an integrated fractured horizontal well numerical simulation model according to seismic data of a target well, logging interpretation data and an engineering parameter range given by an oil production scheme; the integrated fractured horizontal well numerical simulation model is used for simulating single well yields under different section intervals and different single-section carbon dioxide injection amounts by adopting a section-separated gas injection method; drawing a parameter optimization chart based on the single well yield and the carbon dioxide injection section number obtained under different section distances and different single-section carbon dioxide injection amounts; and according to the parameter optimization plate, determining the final segment spacing and the single-segment carbon dioxide injection amount. While the recovery efficiency is improved, the construction efficiency is improved, and the fracturing cost is saved.

The application discloses a kind of suitable for SCR denitration ammonia injection device and device, including ammonia injection pipe and the ammonia injection port of setting at ammonia injection pipe end, ammonia injection pipe includes ammonia main pipeline, branch pipeline and branch pipeline;Along ammonia main pipeline circumferential direction, equidistantly there are several branch pipelines;In branch pipeline, equidistantly and parallelly there are several vertical branch pipeline branch pipelines;Several branch pipelines are in the same plane, plane vertical branch pipeline;In branch pipeline, there is vertical plane ammonia injection port;Ammonia injection port gas outlet direction is same with ammonia main pipeline inner gas flow direction.The ammonia injection device suitable for SCR denitration designed in the application, including branch pipeline and branch pipeline, ammonia injection pipeline because each part branch pipe length is small, and the difference of branch pipeline diameter is not big, so it can reduce the flow resistance of ammonia in pipeline.

The utility model discloses a valve assembly, heat exchange device and air conditioner, valve assembly includes: valve island, the flow passage is defined in the valve island, and the valve island forms with the first interface, valve core interface and flow passage interface who communicate with flow passage, and valve core interface is located between the first interface and flow passage interface, expansion valve, expansion valve is installed in the valve core interface position, and expansion valve is communicated between the first interface and flow passage interface, filter assembly, filter assembly is located in the flow passage, and is located between the first interface and valve core interface, and filter assembly forms a plurality of filter holes, and a plurality of filter holes include a plurality of first filter holes and a plurality of second filter holes, and the equivalent diameter of first filter hole is different with the equivalent diameter of second filter hole. According to the valve assembly of the utility model, can effectively filter the refrigerant that flows through in flow passage, can realize the fractional filtration of the impurity in refrigerant, improves the filtering effect and filtering efficiency, can also reduce the flow resistance, guarantees that refrigerant passes through valve assembly normally smoothly.

This application belongs to the technical field of cooling equipment, and particularly relates to a device for improving the power generation efficiency of a waste heat generator set by cooling. The device includes a condenser, an inlet water pipe at the condenser's inlet, a cooling pipe on the inlet water pipe, at least one heat exchange component on the cooling pipe, and a ventilation cooling system or a liquid cooling system on the outside of the cooling pipe. The ventilation cooling system or liquid cooling system works in conjunction with the cooling pipe to lower the temperature inside the cooling pipe. This application, by installing a cooling pipe on the inlet water pipe and dissipating heat from the cooling pipe, lowers the temperature of the circulating water flowing through the cooling pipe, thereby increasing the vacuum degree of the condenser and thus improving the power generation efficiency and output of the waste heat generator set.

The utility model belongs to fertilizer technical field especially a kind of fertilizer nitrogen content monitoring device, including frame and the synthetic tower placed on the frame, the outside of the synthetic tower is provided with mixing mechanism, the mixing mechanism includes blade, the blade is generated vortex and shearing action by guiding airflow to realize the turbulent mixing of nitrogen and hydrogen, by setting monitoring mechanism, the quantitative analysis of nitrogen content in gas is realized, sampling probe extracts gas sample from air inlet pipe, the outlet of sampling probe is fixedly communicated with filter tank by electric heat tracing pipeline, ensure that gas keeps constant temperature in transmission process, prevent condensation, the inside wall of filter tank is installed with coarse filter layer, fine filter layer, dehumidification layer and oil removal layer from bottom to top in order, realize multistage filtration and purification to gas.

The utility model discloses an offshore triangular flow blocking net cage which comprises a first buoyancy pipe, a second buoyancy pipe and a third buoyancy pipe, the first buoyancy pipe, the second buoyancy pipe and the third buoyancy pipe are connected end to end to form a triangular structure, and a reinforcing pipe is arranged in an area defined by the first buoyancy pipe, the second buoyancy pipe and the third buoyancy pipe. The first buoyancy pipe, the second buoyancy pipe and the third buoyancy pipe are connected through reinforcing pipes. The triangular structure formed by combining the first buoyancy pipe, the second buoyancy pipe and the third buoyancy pipe has good stability, the structural strength and the anti-flow stability of the net cage are improved, the vertex angle of the triangle formed by connecting the first buoyancy pipe and the second buoyancy pipe is arranged towards the seawater flowing direction, and seawater flow division is effectively achieved; meanwhile, the first buoyancy pipe and the second buoyancy pipe are obliquely arranged, so that the water flow diffuses towards the two sides and flows backwards along the first buoyancy pipe and the second buoyancy pipe, and the pressure of the incident flow surface of the net cage is effectively reduced.

The utility model discloses a top air outlet type air conditioner outdoor unit which comprises a machine shell comprising a base plate formed by splicing a first bottom plate and a second bottom plate. The outdoor heat exchanger is arranged on the base plate and defines a heat exchange space, and a notch is formed in the side wall of the outdoor heat exchanger and comprises a first notch section and a second notch section. The compressor is arranged in the heat exchange space, is arranged on the first bottom plate and is close to the first notch section; the gas-liquid separator is arranged on the second bottom plate and is close to the first bottom plate; the oil separator is arranged on the first bottom plate and located on the side, away from the first notch section, of the compressor. The stop valve is close to the first notch section relative to the gas-liquid separator, and the projection of the stop valve on the chassis is located on the second bottom plate; and the four-way valve is arranged on the side, away from the first notch section, of the stop valve, the height of the four-way valve is between the height of the stop valve and the height of the gas-liquid separator, reasonable layout of all parts of the outdoor unit in a limited space is achieved, and manufacturability and maintainability are both considered while the space utilization rate is increased.

This invention discloses a nitrogen-driven pneumatic directional drilling equipment for downhole cuttings removal in soft coal seams, comprising a nitrogen drive mechanism and a directional drilling rig. The directional drilling rig has a directional drill string assembly structure, which includes a drill rod. A probe outer tube is coaxially sleeved inside the drill rod, and a measuring probe is coaxially sleeved inside the probe outer tube. The measuring probe is used to measure the gas flow rate and pressure in the borehole. An annular downward air chamber for nitrogen gas flow is formed between the inner wall of the probe outer tube and the outer wall of the measuring probe. An air inlet is opened on the outer wall of the drill rod at the lower part, and an annular upward air chamber for nitrogen gas flow is formed between the inner wall of the drill rod above the air inlet and the outer wall of the probe outer tube. A trumpet-shaped wind shield, wider at the bottom and narrower at the top, is connected to the outer wall of the drill rod above the air inlet. This invention also discloses a corresponding borehole cuttings removal method. This invention significantly reduces the resistance to airflow, achieving faster drilling speeds and removing more cuttings under the same air volume and pressure.

This application relates to a motor heat dissipation mechanism for a vacuum cleaner, belonging to the field of mechanical heat dissipation. It includes a stator, a rotor, an air inlet housing, a rotating shaft, an end cover, a moving impeller, and a first stationary impeller. The stator is fixed inside the first stationary impeller, and the moving impeller is located inside the air inlet housing. There is a gap between the outer circumferential wall of the moving impeller and the inner wall of the air inlet housing. The first stationary impeller is fixedly connected to the end cover, and the rotating shaft is rotatably connected to the first stationary impeller. A cooling air duct is provided between the inner wall of the first stationary impeller and the outer wall of the stator. A baffle shell is fixedly provided on the outer circumferential wall of the first stationary impeller and is fixedly connected to the air inlet housing. A second stationary impeller is coaxially fixed at the end of the first stationary impeller near the moving impeller, and the outer circumferential wall of the second stationary impeller is in contact with the inner wall of the air inlet housing. A cover plate for mounting a circuit board is fixedly provided at the end of the end cover away from the first stationary impeller, and the end cover has several ventilation holes. This application has the effect of reducing dust accumulation in the vacuum cleaner motor and achieving simultaneous and efficient heat dissipation.

The application provides a heat exchange tube and a heat exchanger. The heat exchange tube comprises a tube body (1), an inner tooth (2) is arranged in the tube body (1), the inner tooth (2) comprises a first inner tooth unit (21) and a second inner tooth unit (22) which are different in height and / or shape, the first inner tooth unit (21) and the second inner tooth unit (22) are arranged at intervals, and a fluid passage (3) is formed between adjacent first inner tooth units (21) and second inner tooth units (22). The heat exchanger has the heat exchange tube. The application solves the problems of excessive flow resistance of fluid, excessive pressure loss and limited heat exchange efficiency improvement caused by the continuous thread line structure in the prior art.

The utility model discloses a slide block glue feeding structure of a plastic mould, which comprises a diving gate assembly and a slide block of the mould, the diving gate assembly comprises a diving port and a runner, the runner is arranged in an upper mould of the mould, the diving port is arranged in the slide block, and when the mould is closed and the slide block enters a core, the runner is arranged in the slide block. The diving opening is communicated with a cavity of the injection mold, a connecting section is arranged between the diving opening and the runner, the end, away from the cavity, of the diving opening is communicated with the end, located in the mold, of the runner through the connecting section, and the connecting section is vertically arranged; the diving opening is obliquely arranged relative to the horizontal plane, and the included angle between the diving opening and the connecting section is an obtuse angle. According to the utility model, the arrangement of cold runners is reduced, the length of the whole runner is shortened, and the forming period is shortened, so that the efficiency is improved.

A large flow quick response liquid supplement valve structure, one end of the iron core assembly is connected with the valve seat assembly, the shell is sleeved outside the iron core assembly and the valve seat assembly, the iron core assembly includes a moving iron core and a static iron core, one end of the static iron core is connected with the moving iron core, the moving iron core is connected with the valve seat assembly, a plurality of connecting protrusions are protrudingly arranged on the side end face of the static iron core close to the moving iron core, and the moving iron core moves in the shell towards the static iron core and is connected with the connecting protrusions. Through the cooperation of the connecting protrusions and the moving iron core, the accurate guidance and stable connection of the moving iron core are realized, and the response speed of the liquid supplement valve is effectively improved. The multi-stage design of the valve seat assembly, especially the pre-tightening spring on the third valve seat, effectively alleviates the influence of liquid impact on the valve seat, reduces wear and deformation, and improves the durability of the liquid supplement valve. The U-shaped structure of the second valve seat optimizes the liquid flow path, reduces the flow resistance, and helps to realize large flow liquid supplement.

The application belongs to the field of fluid control valves and provides a double-curved-channel regulating valve, which comprises a valve body and a valve core. The valve body forms an upper chamber, a lower chamber, an intermediate channel connecting the upper chamber and the lower chamber, an input flange and an output flange coaxially and separately arranged, an input channel connected to the upper chamber formed on the input flange, and an output channel connected to the lower chamber formed on the output flange. The input channel and the output channel are both curved channels and are symmetrically arranged about the geometric center of the intermediate channel. The valve core is arranged inside the valve body and is used for adjusting the opening degree of the intermediate channel.

The utility model discloses a valve mechanism of micro -fluidic chip, including the upper valve disc of installing in the inside of micro -fluidic chip, the integral molding of a plurality of connecting columns of upper valve disc bottom end and the integral molding of a plurality of connecting column bottom end lower valve seat, the inside of lower valve seat is provided with a plurality of both ends all through to the arc drainage cavity of lower valve seat outside. Upper valve disc, lower valve seat in the utility model are driven by outside micro -motor and rotate in micro -fluidic chip, and the arc drainage cavity in lower valve seat is communicated with the corresponding flow passage in micro -fluidic chip, and the elastic retreat -stopping structure, the anti -slip groove maintain the rotation angle of upper valve disc, lower valve seat.

The invention relates to the technical field of heat management, provides a self-adaptive enhanced heat exchange method based on a high-temperature shape memory alloy, and further provides a self-adaptive enhanced heat exchange channel which is composed of a heat exchange channel pipe wall and a plurality of self-adaptive fins arranged on the outer side or the inner side of the pipe wall. The self-adaptive fin is of an integrated three-section structure and comprises a base connecting section, a functional gradient transition section and a self-adaptive functional section. Shape memory training is conducted on the self-adaptive fins or the self-adaptive functional sections, so that the self-adaptive functional sections have the temperature-induced deformation capacity; according to the thermal environment, the self-adaptive fins are automatically switched between the low-temperature / low-thermal-load state and the high-temperature / high-thermal-load state, and intelligent regulation and control over the heat exchange process are achieved. According to the self-adaptive heat transfer material, on-demand intelligent regulation and control of the heat exchange performance are achieved, the fixed tradeoff relation between the performance and the resistance is broken, and the technical problem that an existing self-adaptive heat transfer material cannot meet the high-temperature environment application requirement is effectively solved.

This utility model relates to a water circuit component and a coffee machine, belonging to the field of coffee brewing. The water circuit component is characterized by comprising: a liquid supply component, which has a liquid storage chamber; a first heating component, which is connected to the liquid supply component and is used to heat the flowing liquid; an adapter, which is connected to the first heating component; a coffee brewing component, which is connected to the adapter; a liquid dispensing component, which is connected to the coffee brewing component; and a steam output component, which is connected to the adapter and the water circuit component. This simplifies the water circuit layout, reduces pipe bends and complex connections, lowers liquid flow resistance, and ensures that the liquid can flow quickly and stably to each component. The steam output component, connected to the adapter, can utilize the heated liquid to generate steam for operations such as frothing milk and heating beverages.

The utility model provides a deep well multistage centrifugal water pump, and belongs to the technical field of deep well water pumps. The deep well multistage pump solves the problem that in the prior art, power loss of a deep well multistage pump is too large. The multi-stage centrifugal pump comprises a water inlet seat, a sealing ring, a pump shell, a water outlet seat, a pump shaft and a multi-stage impeller assembly, the water inlet seat, the sealing ring, the pump shell and the water outlet seat are fixedly connected in sequence, the pump shaft sequentially penetrates through the water inlet seat, the multi-stage impeller assembly and the water outlet seat, and the multi-stage impeller assembly is installed in the pump shell. The multi-stage impeller assembly comprises a front guide vane, a plurality of impeller bodies, a plurality of fluid directors and a rear cover plate, each fluid director is of an annular structure as a whole, a through hole is formed in the center of each fluid director, a supporting face is formed in each fluid director and is in a high-low shape, and a circulation hole is formed in the side end face in each supporting face; a first worm-shaped flow guide channel and a second worm-shaped flow guide channel are formed in the front side and the rear side of the supporting face respectively, the supporting face is close to the front side of the flow guider, and a containing cavity is formed in the rear side of the supporting face. The utility model has the advantage of less power loss.

The utility model relates to a ventilation equipment field provides a kind of air duct assembly, air conditioning system and vehicle.Wind channel component includes air supply device, air supply device includes wind box, and wind box is opened with air inlet and air outlet, air inlet is provided with filter piece, and the position corresponding with air inlet in wind box is provided with air guide piece;Distribution box, fluid communication is in air outlet, and distribution box is provided with valve group, and distribution box includes first air duct, second air duct and third air duct, first air duct is fluid communication with the driver's room of vehicle, second air duct is fluid communication with the traction motor cabin of vehicle, third air duct is fluid communication with the passenger room of vehicle, and valve group is used to distribute the air intake of first air duct, second air duct and third air duct.The air duct assembly can make the airflow output of each air duct stable, avoid the air supply fluctuation caused by external wind pressure variation, ensure the comfort of driver's room, passenger room and the heat dissipation effect of traction motor cabin, improve the reliability of vehicle operation, simplify the structure of air duct assembly.