1290 results about "Inlet flow" patented technology

The invention provides a thermal behavior experiment system and method under a narrow rectangular channel reflooding cooling condition. The system comprises a heating water storage tank, a nitrogen tank, a steam tank, a shield pump, a preheating section, a first direct-current power supply, a second direct-current power supply, a narrow rectangular channel test section, a steam-water separator, a surge tank, a flow control valve, a silencer and an electromagnetic valve. The experimental working medium is deionized water, and re-submerging cooling experiments under different system pressures, working medium supercooling degrees, heating wall surface heat flux densities, working medium submerging speeds, heating wall surface initial temperatures and channel interior initial liquid levels can be carried out on an experimental section of a narrow rectangular channel structure. The device is suitable for narrow rectangular channel structures with different sizes, and can be used for carrying out re-submerging experiments on experiment sections with single-plate double-channel, double-plate three-channel and more channels. The system pressure and the inlet flow in the submerging process can be kept stable, and it can be ensured that the supercooling degree of a working medium, the heating wall surface temperature and the initial liquid level are controllable.

The invention discloses a surge valve control method and device, electronic equipment and a vehicle, relates to the field of engines, and aims to determine whether an engine is in a target working condition representing that a supercharger is liable to have a surge phenomenon or not. And on the basis of determining that the engine is in the target working condition, according to the intensity of the change of the operation state of the engine under the target working condition, when the engine is determined to be in a relatively strong transient working condition, whether a surge valve is opened or not is determined in time in combination with the opening degree of a throttle valve. And when it is determined that the surge valve is not opened, whether the surge valve is opened or not is further determined according to the air inlet flow of the engine and the opening degree of the throttle valve. Whether the surge valve is opened or not is judged according to the target working condition, the strong transient working condition and the surge flow of the engine in sequence, the multiple working conditions and operation conditions of the engine are synthesized, the opening condition of the surge valve is more accurately determined, the situation that the surge valve is opened abnormally can be effectively reduced, and therefore the situation that power of the engine is insufficient is effectively reduced.

Embodiments of a manifold of a hydraulic fracturing system include a junction having an inlet flow bore. The junction can include an integrated flow junction and valve check assembly having a body including a central portion and one or more side portions. The central portion can be positioned between a pair of manifold sections of the manifold and attached thereto. The one or more side portions extend radially from the central portion and include an inlet bore through which a pressurized fluid is received and supplied to the manifold. One or more check valves is positioned along the inlet bore so as to be integrated within the body of the junction.

The invention belongs to the technical field of aero-engines, and particularly relates to an aero-engine air inlet flow pipe calibration method, which comprises the following steps of: measuring internal flow field parameters in a standard flow measurement section through a plurality of sensors, and calculating theoretical air mass flow qm1TH of the standard flow measurement section; the actual air mass flow qm1ACT of the standard flow measuring section is measured through a negative pressure air suction type flow standard device; the outflow coefficient of the standard flow measurement section is calculated; connecting a calibrated engine air inlet flow pipe A2 to the front of the standard flow measuring section, and connecting the engine to the rear of the standard flow measuring section; calculating the actual air mass flow of the standard flow measurement section, and taking the actual air mass flow as the actual air mass flow qm4ACT of the calibrated engine air inlet flow pipe A2; and the outflow coefficient of the calibrated engine air inlet flow pipe A2 is calculated based on the theoretical air mass flow qm4TH and the actual air mass flow qm4ACT of the calibrated engine air inlet flow pipe A2.

The invention provides a modularized flow guide type multi-stage pump, and belongs to the technical field of water pumps. The modularized flow guide type multi-stage pump comprises a pump body assembly and a driving motor, the pump body assembly is formed by sequentially connecting a pump head pattern plate, a multi-stage pump shell, a multi-stage flow guide module set and a water retaining sealing cover, the pump head pattern plate is adjustably connected with a connecting end cover of the driving motor through a long screw rod, and the stage number of the pump can be adjusted by increasing or decreasing the number of the flow guide shells. Different lift requirements are met; the multi-stage flow guide module group is mainly composed of a water inlet flow guide shell, a transmission flow guide shell and a water outlet flow guide shell, a closed impeller is arranged in each flow guide shell to form an independent flow guide module, fluid is guided by spiral flow guide blades between the flow guide shells to orderly flow and smoothly transmit, and turbulent flow eddy current loss is reduced; and the water retaining sealing cover realizes double leakage prevention through a stepped sealing flange and mechanical sealing. The high-lift and high-flow pump has the advantages of being easy to disassemble, assemble and maintain, modularized and flexible to adjust, low in energy loss, high in lift, high in flow and high in sealing performance.

The invention provides a pressure control system of an MOCVD (Metal Organic Chemical Vapor Deposition) reaction cavity and MOCVD epitaxial equipment, and the system comprises a cavity in which a reaction cavity is defined; the exhaust pipeline is communicated with the reaction cavity; the first pressure gauge is fixed on the cavity body, and the first pressure gauge is used for detecting the gas pressure in the reaction cavity; the exhaust valve is configured to control the exhaust flow through the opening degree of the valve; the vacuum pump is used for extracting gas in the reaction cavity; the mass flow controller is configured to be capable of detecting and controlling the flow of gas flowing into the reaction cavity; and the controller is configured to control the valve opening degree of the exhaust valve and / or control the gas inlet flow of the mass flow controller according to the gas pressure detected by the first pressure meter. According to the pressure control system of the MOCVD reaction chamber, the first pressure meter, the exhaust valve and the mass flow controller are arranged on the chamber body, and the gas pressure can be adjusted in real time, so that the product quality can be effectively improved.

The ultra-high-temperature water-cooling switch valve comprises a valve body, a valve cover, a support, an actuator, a valve rod, a valve clack and a valve seat, an inlet flow channel, a middle cavity and an outlet flow channel which are sequentially communicated are formed in the valve body, a shaft hole is formed in the valve cover, and the valve rod penetrates through the shaft hole and extends into the middle cavity to be connected with the valve clack. The outer end of the valve rod is connected with the output end of the actuator, and the valve seat is installed between the outlet flow channel and the middle cavity and used for being in sealing fit with the valve clack when the valve is closed. An opening and closing piece cooling structure is arranged on the valve clack and the valve rod, a valve seat cooling structure is arranged on the valve seat, an inlet cooling structure is arranged in the inlet flow channel, a middle cavity cooling structure is arranged in the middle cavity, an outlet cooling structure is arranged in the outlet flow channel, and a valve deck cooling structure is arranged on the valve deck. Multiple cooling loops are adopted for cooling all parts of the valve, structural failures such as deformation caused by thermal barrier cold contraction under the alternating working condition are prevented, and normal operation of a valve pressure-bearing shell and a sealing element under the ultra-high-temperature working condition is guaranteed.

The invention discloses a movable frame device for a high-power turboprop engine test bed and the engine test bed. The movable frame device comprises a movable frame framework, a front mounting seat and a counterweight system. The movable frame framework is arranged below the static frame device and used for being connected with the static frame device through a plurality of spring pieces arranged on the periphery of the movable frame framework, and then the rack system used for measuring the thrust of the turboprop engine is formed. The front mounting seat is used for being connected with an engine mounting rack for mounting a turboprop engine in a fast mounting manner so as to mount and support the turboprop engine to be measured. And the counterweight system is used for balancing the total weight of the turboprop engine and the engine mounting frame, so that the gravity center of the rack system is positioned in the center defined by the plurality of spring pieces. According to the movable frame device, the air inlet flow field of the propeller is not influenced by the size of the frame of the movable frame device, so that the engine performance is not influenced, the test result is high in accuracy, the test is safe and reliable, and the installation position of the propeller does not interfere with the structure of the movable frame device.

The invention provides a top structure of a high synchronous test number tester, which comprises a load plate, and two groups of socket assemblies are symmetrically arranged on the load plate. A plurality of signal connectors are arranged around each group of socket assemblies; the socket assembly comprises a plurality of chip sockets; a socket supporting plate, a rectifying plate and an airtight box are sequentially arranged below the load plate corresponding to the socket assembly from top to bottom; a through air inlet is formed in the bottom of the airtight box; air inlet flow channels are uniformly formed in the bottom surface in the airtight box and are communicated with the air inlet; a plurality of air uniformizing holes penetrate through the rectifying plate; the air uniformizing holes are formed above the air inlet flow channel and are communicated with the air inlet flow channel; a plurality of first vent holes are formed in the socket supporting plate in a penetrating manner, and the first vent holes are communicated with the space above the rectifying plate; a plurality of second vent holes are formed in the load plate in a penetrating mode, a third vent hole is formed in each chip socket of the socket assembly in a penetrating mode, and when the socket assembly is installed on the load plate, the second vent holes are communicated with the third vent holes in a one-to-one correspondence mode.

A method for controlling a flow regulating valve (6) of a filling machine (1), controlling the flow of pourable food product, envisages: receiving an inlet pressure measurement (PIN) from a pressure sensor (14); receiving an inlet flow measurement (FIN) from a flow meter (16); determining a control signal (Sc) for controlling an operating position of the flow regulating valve (6) by combined contributions (C1, C2) of a flow feedback control module (22), receiving at its input a flow set point (FSP) and the inlet flow measurement (FIN) and generating a first control contribution (C1) indicative of a difference between the inlet flow measurement and the flow set point; and a flow feed-forward control module (20), receiving at its input the inlet pressure measurement (PIN) and the flow set point (FSP) and generating a second control contribution (C2) as a function of the flow set point and inlet pressure measurement, using pre-stored fluid-dynamic maps, which may be a result of a characterization of the flow regulating valve in a test condition. The flow feed-forward control module uses the fluid dynamics maps in a dynamically adaptive manner, depending on different operating conditions of the filling machine and / or the related pourable food product, thereby adapting to the same different operating conditions and / or the pourable food product.

The invention belongs to the field of fluid machinery, and particularly discloses a centrifugal pump volute with a composite noise reduction structure. The centrifugal pump volute comprises a volute body with the base circle radius being R. A volute chamber is formed in the volute body, and a plurality of micro flow deflectors are distributed on the inner side of an inlet of the volute body in the circumferential direction; two sections of semicircular grooves are symmetrically formed in the upstream section of the volute inner wall baffle tongue front and back along the spiral line; two flow guide plates are arranged at a baffle tongue of the volute body, the flow guide plate close to one side of an inlet of the volute body is a front flow guide plate, and a plurality of flow guide holes are formed in the front flow guide plate; a plurality of cavities are uniformly arrayed on the wall surface of the baffle tongue of the volute body; and the bending directions of the micro flow deflectors and the flow deflectors are consistent with the water flowing direction. Inlet flow is optimized through the micro flow deflectors, vortex is restrained through the semicircular grooves, pressure pulsation is reduced through cooperation of the flow deflectors and the cavity structure, the hydraulic performance is kept while fluid noise is effectively reduced, and the comprehensive performance is obviously improved.

The invention discloses a combustion chamber nonlinear stability prediction method based on multi-input thermo-acoustic disturbance modeling. The method is used for evaluating thermo-acoustic stability of combustion chambers of aero-engines, gas turbines and the like. According to the method, geometric, operation and analysis parameters are input, and cooling flow distribution is calculated; solving an effective equivalence ratio, a heat release rate and a temperature field, and calculating an acoustic modal frequency; constructing an equivalence ratio and inlet flow double-disturbance MISO transfer function, and generating an FTF curve; and judging oscillation through a limit cycle detection algorithm, calling a Tanh / PowerLaw model to calculate a saturated heat release rate, and finally visually outputting a result. Multi-factor coupling accurate modeling is achieved, intervention can be conducted in the initial stage of design, calculation only needs several minutes, the prediction precision and efficiency are improved, the research and development cost is reduced, and the safety of the combustion chamber is guaranteed.

The invention belongs to the technical field of fire fighting, and particularly relates to a groove connection type fire pump adapter which comprises a main body, a hand wheel, a valve rod and a valve plate are arranged on the main body, a supporting piece comprises a fixing block connected with the main body, and a supporting plate abutting against the valve plate is rotationally connected to the fixing block. The bottom of the fixing block is provided with an annular part for containing the supporting plate to rotate downwards, the rotating piece rotates to drive the pushing block at the bottom to rotate synchronously and be embedded into the first clamping groove, meanwhile, the arc face abuts against the arc face on the rack, and therefore the whole rack is pushed to move backwards, and the meshed driving wheel is driven to be transmitted to the transmission wheel. The transmission wheel rotates synchronously and drives the supporting plate to rotate downwards, so that the aperture of the supporting piece abutting against the valve plate is enlarged, water entering from the connector of the main body flows into the bottom pipeline of the main body more smoothly, and meanwhile, under the condition that the water flow is not changed, the connector of the bottom pipeline is enlarged, and water flow entering is not too rapid. Inlet flow speed is reduced, and water flow is more stable.

The invention discloses a gas purification real-time monitoring method, system and device and a medium, and belongs to the technical field of gas purification. The method comprises the following steps: a data acquisition stage: acquiring inlet gas flow and outlet component data; in the adsorbent state monitoring stage, the adsorbent state is monitored in real time through the monitoring point position in the adsorption barrel; in the adsorption capacity calculation stage, the residual adsorption capacity is predicted through an impurity penetration curve model on the basis of inlet flow and outlet component data, and bidirectional verification and correction are carried out on the residual adsorption capacity and an internal monitoring state; in the regeneration time prediction stage, the optimal regeneration time is dynamically predicted according to discharged gas component analysis and residual adsorption capacity; in the real-time regulation and control stage, parameters of the purifier and the regenerative heater are adjusted in real time according to the prediction result. Accurate evaluation of the state of the adsorption cylinder and intelligent optimization of the regeneration process are achieved, the utilization rate of the adsorption cylinder is remarkably increased, and the total energy consumption of regeneration is reduced.

The invention discloses digital intelligence powder type distribution-free variable viscosity fracturing fluid skid-mounted equipment and a control method thereof, and belongs to the technical field of oil and gas field development. The equipment comprises a stirring mechanism, a feeding mechanism, a water feeding mechanism and a discharging mechanism which are centrally controlled through a control box. The feeding mechanism adopts a first screw conveyor to convey solid materials to the stirring tank body; the water supply mechanism supplies water to the tank through a water supply pump and a water outlet pipe with an electromagnetic valve, and the water quantity is monitored by a water inlet flow sensor; the discharging mechanism outputs the mixed liquid through a discharging pump, and the viscosity of the fracturing fluid is detected in real time through a viscosity sensor. The control box is connected with all the sensors and execution components, and automatic adjustment and closed-loop control of the material proportion are achieved by collecting flow and viscosity data. According to the invention, accurate and automatic preparation of the fracturing fluid is realized, the problems of inaccurate traditional manual proportioning and poor stability are effectively solved, and the fluid preparation quality and the operation efficiency are remarkably improved.

An embodiment of a manifold of a hydraulic fracturing system includes a flow cross junction including an inlet flow bore. In addition, the manifold includes a coupling adapter including an external shoulder and a connection device. The connection device is to connect to an output of a pump of the hydraulic fracturing system, and the coupling adapter is removably inserted within the inlet flow bore such that the connection device is positioned outside of the inlet flow bore. Further, the manifold includes a retainer ring connected to the flow cross junction and compressed against the external shoulder.

The cooling runner system comprises a water inlet, a water inlet runner, a water uniformizing device, a water outlet runner and a water outlet, the water inlet runner penetrates through a rotating shaft and is located on the axis of the rotating shaft, the water inlet is formed in the side edge, close to the lower portion, of the water inlet runner, and the output end of the water inlet is connected with the input end of the water inlet runner; a water uniformizing device is arranged in the crucible body, the top of the water inlet flow channel penetrates through the center of the bottom of the crucible body and the water uniformizing device to reach the upper portion of the water uniformizing device, the water uniformizing device comprises a water uniformizing disc and guide pieces, the upper side surface and the lower side surface of the water uniformizing disc are each provided with a plurality of guide pieces diverging towards the periphery, and the guide pieces on each side are arranged in the circumferential direction of the circle center of the water uniformizing disc. The water outlet runner is arranged on the outer ring of the water inlet runner, so that the inner wall of the water outlet runner and the outer wall of the water inlet runner form a water flow passageway for water outlet, the input end of the water flow passageway is connected with the output end of the water uniformizing device, and the output end of the water flow passageway is connected with the water outlet.

The invention relates to the field of evaporative coolers, and provides a tube box type evaporative cooler which comprises a box body, a heat exchange cavity is formed in the interior of the box body, the bottom end of the interior of the heat exchange cavity is fixedly connected with a discharging barrel used for discharging redundant cooling water and steam, the top side of the discharging barrel is fixedly connected with a cooling tube, and the top side of the cooling tube is fixedly connected with a heat exchanger. The cooling device comprises a plurality of cooling pipes, the input ends of the plurality of cooling pipes are communicated, the output ends of the plurality of cooling pipes are communicated, the outer walls of the cooling pipes are provided with annular grooves and cooling fins used for heat dissipation, and the cooling pipes are spirally arranged along with the cooling pipes. Air pressure expansion caused by the fact that air flow is hindered during air inlet can be fully used as power, relevant performance optimization and resource utilization of the cooler are carried out, under the condition that normal cooling work is not hindered, the air inlet flow of cooling air and the spraying flow of cooling water of the cooler are optimized, and the cooling efficiency of the cooler is improved. Therefore, the overall performance and the operation economy of the equipment are improved.

The invention discloses an anti-surge control method for a compressor unit, and particularly relates to the field of operation control of the compressor unit, a plurality of sensor terminals for pressure, flow, temperature and the like are deployed in the installation and debugging stage of the compressor unit, working parameters such as air inlet pressure, flow, exhaust pressure and the like are collected in real time, and data are preprocessed after collection; smoothing data by adopting a moving average filtering method, cleaning abnormal values according to a 3 sigma principle, processing missing values according to a missing proportion and normalizing the missing values, constructing an operation condition model based on preprocessed data, and calculating anti-surge threshold values in low, medium and high load areas by combining parameters such as air inlet flow and exhaust pressure; and constructing an exhaust pressure and intake flow prediction model by using historical data, and predicting a future state. The surge state is judged by comparing the predicted value with the threshold value, then the opening degree of the air inlet and exhaust adjusting valve is adjusted, stable operation of the compressor unit is guaranteed, the surge phenomenon is effectively prevented, and the operation safety and reliability of the compressor unit are improved.

The invention provides a high-pressure cavitation valve which comprises a valve body, a valve core, a valve core, a valve core, a valve core, a valve core, a valve core, a valve core and a valve core, and is characterized in that the valve body is internally provided with a mounting cavity and is provided with a flow inlet channel and a flow outlet channel; the valve cover is arranged at the upper part of the valve body and used for covering the upper side of the mounting cavity; the valve assembly comprises a valve element, a valve rod, a mounting seat, a valve seat and a throttling module, the mounting seat, the throttling module and the valve seat are sequentially arranged from top to bottom, a movable cavity of the valve element is formed in the mounting seat and the throttling module, the valve element is mounted in the movable cavity and used for acting up and down to be matched with the valve seat to open and close the valve, and the valve rod penetrates through the valve cover and then is connected with the valve element; the throttling module at least comprises two round throttling laminations which are arranged in an up-down overlapped mode, a center hole is formed in the center of each throttling lamination in a penetrating mode, a labyrinth flow channel used for reducing pressure and noise of media is formed between every two adjacent throttling laminations, and the labyrinth flow channels are not communicated with one another at the overlapped portions of the throttling laminations. The throttling module in the scheme can effectively play roles of throttling, pressure reduction and the like.

The invention discloses a fire grate, a combustor and a water heater, and relates to the technical field of water heaters, the fire grate comprises a fire grate body and a combustion head, the fire grate body is provided with a mixing cavity and at least two air inlet flow channels, the mixing cavity is provided with a fire opening, the exhaust ends of the at least two air inlet flow channels are communicated with the mixing cavity, and the combustion head is communicated with the mixing cavity. The gas inlet end of each gas inlet flow channel forms an injection opening, each injection opening is used for conveying gas and air to the corresponding gas inlet flow channel, the combustion head is arranged on the fire opening, and the combustion head is provided with a plurality of fire holes communicated with the mixing cavity. According to the technical scheme provided by the invention, the primary air coefficient of the fire grate can be increased, the overall high temperature of the combustion head is prevented, and the flame distribution of the combustion head is more uniform, so that the local high temperature of the combustion head is avoided, the generation of thermal nitrogen oxides can be greatly reduced, and the emission of harmful substances is reduced.

The invention provides an aircraft component fault intelligent diagnosis and maintenance control system, and relates to the technical field of aircraft component diagnosis. A stall modeling module of the system establishes an aeroelastic coupling equation for quantifying stall behaviors on the basis of collected pressure disturbance data of an air inlet flow field of an air compressor and blade row vibration response information. The elastic response deduction module discretizes the equation through a state conversion operator and then embeds the equation into a graph neural network node update function. The graph embedding coupling recognition module recognizes blade tip gap mutation behaviors induced by local stall and time sequence precursor characteristics of the blade tip gap mutation behaviors by using a node state evolution trajectory output by the graph neural network, and constructs a surge precursor evolution path. And the early warning output module carries out instability trend judgment on the surge precursor evolution path, and outputs a maintenance suggestion and an early warning identifier aiming at a blade fracture fault, so that the structure failure risk caused by the surge of the gas compressor is effectively predicted, and the accuracy and timeliness of fault diagnosis of aircraft parts are remarkably improved.

The invention relates to the technical field of compressors, in particular to a series-connection automobile towing compressor system and an automatic surge control method. The series-connection automobile towing compressor system comprises a plurality of stages of automobile towing compressors, a plurality of temperature reduction devices, a bypass return valve, a plurality of temperature reduction adjusting valves and a plurality of orifice plate flowmeters. The problems that in the prior art, cost is high, energy consumption is large and the control effect is not ideal are effectively solved, the multiple stages of automobile dragging compressors are arranged in series and matched with the temperature reducing device and the bypass backflow valve, effective circulation and temperature control of media are achieved, cost of independently using a surge backflow valve in the prior art is reduced, and meanwhile the control effect is good. Through the arrangement of the vortex shedding flowmeter, the pressure sensor, the temperature sensor and the rotating speed sensor, the inlet flow, pressure, temperature and rotating speed of each stage of compressor are accurately measured, in combination with theoretical surge pressure ratio calculation, the surge risk is pre-judged in advance and automatically controlled, and energy consumption increase caused by premature intervention of a bypass return valve at the low rotating speed is avoided.

The invention relates to the technical field of magnetic pumps, and discloses a reverse driving impurity type magnetic pump which comprises a pump chamber, a water inlet, a water outlet and an impurity removal channel are formed outside the pump chamber, an impeller is arranged in the pump chamber, and the impeller is connected with an inner magnetic rotor shaft and is connected with an outer magnetic rotor shaft through a motor to drive rotation. Liquid in the water inlet axially flows into the pump chamber, a suction chamber is arranged in the water inlet and is a conical barrel with the cross section area gradually and uniformly shrunk, an inducer is arranged on the side, facing the water inlet, of the impeller, the inducer and the impeller coaxially rotate, the installation angle of blades of the inducer is small, and flow channels between the blades are long and wide. And the number of the blades is 2-4.

The utility model belongs to the technical field of proportional valves, and particularly relates to an electromagnetic proportional valve which comprises a shell, a static iron, a coil, a spring, a movable iron, a valve element and a stabilizing piece, an installation cavity is formed in the shell, the static iron is installed in the installation cavity and connected with the shell, the coil is wound on the peripheral face of the shell, and the movable iron is arranged in the installation cavity and connected with the valve element. The valve element is connected with the end, away from the static iron, of the movable iron, the spring is connected between the movable iron and the static iron, the shell is further provided with a liquid cavity, an inflow channel and an outflow channel, the liquid cavity is formed in the side, away from the static iron, of the valve element, the end, away from the movable iron, of the valve element extends into the liquid cavity, and the inflow channel and the outflow channel are both communicated with the liquid cavity. The stabilizing piece is arranged in the mounting cavity, the moving iron is connected with the stabilizing piece, and the stabilizing piece can limit the moving iron in the radial direction of the moving iron. Radial shaking of the moving iron in the mounting cavity is avoided, stability of the moving iron is improved, collision abrasion between the moving iron and the cavity wall of the mounting cavity is prevented, operation stability of the electromagnetic proportional valve is improved, and the service life of the electromagnetic proportional valve is prolonged.

The embodiment of the application provides a gravity self-balancing uniform water distribution system, which comprises first, second and third stage gravity self-balancing water distribution pipelines. Each second stage gravity self-balancing water distribution pipeline is connected to the first stage gravity self-balancing water distribution pipeline, and each third stage gravity self-balancing water distribution pipeline is connected to the second stage gravity self-balancing water distribution pipeline. The circulating water of the cooling tower is automatically depressurized after entering the first stage gravity self-balancing water distribution pipeline, and flows into each second stage gravity self-balancing water distribution pipeline on the basis of the self-weight of the water to realize double uniform water distribution. The water level height of each second stage gravity self-balancing water distribution pipeline is consistent, and the water inlet flows to the third stage gravity self-balancing water distribution pipeline again. The pressure at each water nozzle directly or indirectly connected to the third stage gravity self-balancing water distribution pipeline is consistent, and the water outlet of each water nozzle and the spraying area are substantially the same, so that uniform water distribution is realized, the water inlet is not affected by the water pressure, and the cooling efficiency of the cooling tower is significantly improved.

The invention provides a compressor multi-cavity axial air inlet casting machine shell structure and a manufacturing method, and belongs to the technical field of compressor axial air inlet machine shells. The compressor multi-cavity axial air inlet casting machine shell structure comprises the steps that an oil gas channel set is arranged in a first blade, the oil gas channel set is made to communicate with a bearing cavity, and the bearing cavity is sealed through a sealing assembly; oil and gas in the bearing cavity are prevented from leaking into the flow channel, interference of oil and gas leakage on axial gas inlet is avoided, the flowing efficiency of axial gas inlet airflow is guaranteed, meanwhile, the oil and gas channel set is formed in the first blade so that the oil and gas channel set can be directly communicated with the bearing cavity, an external pipeline is not needed, the overall structure of the shell is simplified, and the cost is reduced. The manufacturing is convenient; the first machine shell blade assembly is of an integrated structure, the second machine shell blade assembly is of an integrated structure, and on the basis that the first blades and the second blades are added, the number of welded junctions in the machine shell is reduced, so that the tendency of deformation in the machine shell assembling process is reduced, and the axial air inlet flow efficiency is prevented from being reduced.

The invention discloses a fire grate, a combustor and a water heater, and relates to the technical field of water heaters, the fire grate comprises a fire grate body, the fire grate body is provided with a mixing cavity, a first air inlet flow channel and a second air inlet flow channel, the mixing cavity is provided with an air outlet, and the air inlet end of the first air inlet flow channel is provided with an injection opening used for introducing air and fuel gas; the exhaust end of the first air inlet flow channel is communicated with a mixing cavity, the air inlet end of the second air inlet flow channel is provided with an air inlet used for introducing air, the exhaust end of the second air inlet flow channel is communicated with the first air inlet flow channel, and the second air inlet flow channel is used for jetting flow to the first air inlet flow channel. A jet flow angle is formed between the jet flow direction of the second gas inlet flow channel and the gas conveying direction of the first gas inlet flow channel, and the jet flow angle is larger than 45 degrees and not larger than 70 degrees. And the combustion head part is arranged at the air outlet, and the combustion head part is provided with a fire hole communicated with the mixing cavity. According to the technical scheme provided by the invention, emission of carbon monoxide and nitrogen oxide can be reduced.

The invention provides a fluid distributor and a heat exchanger, and the fluid distributor comprises a first plate-shaped body which is provided with an inlet flow path; a second plate-shaped body in which first and second outlet flow paths are formed so as to be spaced apart from each other in the height direction; the flow guide frame is fixed between the first plate-shaped body and the second plate-shaped body in a sealed mode, the interior of the flow guide frame is divided into a first flow guide space and a second flow guide space, the flow guide frame comprises a flow equalizing plate which is adjacent to the inlet flow path in the height direction and located below the inlet flow path, and the flow equalizing plate comprises a flow equalizing plate bottom and a flow equalizing plate extending part; the bottom of the flow equalizing plate is located below the inlet flow path correspondingly, and the flow equalizing plate extending parts extend from the bottom of the flow equalizing plate to the positions above the two sides of the bottom of the flow equalizing plate in the mode of inclining to the height direction. And therefore, fluid flowing in from the inlet flow path is shunted to two sides of the bottom of the flow equalizing plate and is respectively guided to the first flow guide space to flow out from the first outlet flow path and the second flow guide space to flow out from the second outlet flow path. According to the invention, the uniformity and fault tolerance of refrigerant distribution are improved.

The invention provides a wide-adjustment high-reliability electric propulsion system and a control method. The wide-adjustment high-reliability electric propulsion system comprises a pressure adjustment module, a flow adjustment module and a Hall thruster. The flow adjusting module is composed of an electromagnetic valve and a flow distributor. According to the Hall thruster flow distributor, through different previous series-parallel connection relations, on the premise that flow distributors are not added, the Hall thrusters can work in pairs, meanwhile, the backup number of the cathode flow distributor and the anode flow distributor is increased, and the system reliability is improved. By arranging the flow resistance step of the flow distributor, the large-range flow adjusting capacity of the cathode and anode inlets of the Hall thruster can be obtained, and therefore the large-range variable thrust working mode, the cathode large-flow ignition mode and the anode low-flow starting mode of the Hall thruster are achieved.