791 results about "Dynamic pressure" patented technology

The invention relates to a method and system for monitoring the running state of a water pump unit based on the digital twin technology, and belongs to the technical field of pipeline pump monitoring. The method comprises the steps that a digital twin model fusing equipment parameters and environment sensing data is constructed, and multi-dimensional running data such as dynamic pressure, flow, electric energy quality and temperature are collected in real time in combination with the Internet of Things technology; a multi-dimensional correction algorithm is innovatively provided, fluid flow velocity calculation is corrected through pipe opening structure parameters, lift calculation is dynamically corrected through a temperature compensation algorithm and a mechanical wear factor, and dynamic compensation is conducted on the water pump efficiency by introducing a harmonic loss calibration mechanism. Based on a two-channel machine learning model, a fault incidence matrix is constructed by improving a weighted K-means algorithm to realize equipment health state clustering, an efficiency attenuation trend is predicted in combination with an LSTM network, static characteristics and dynamic time sequence data are fused by using an attention mechanism, and finally an accurate fault diagnosis report and a maintenance strategy are generated.

The invention provides a tunnel surrounding rock grouting control method and system, and relates to the technical field of tunnel engineering.The tunnel surrounding rock grouting control method comprises the steps that grouting parameters are obtained, and the grouting parameters comprise grouting pressure and slurry viscosity; performing multi-dimensional real-time monitoring on the surrounding rock fracture, and constructing a dynamic three-dimensional geologic model through the multi-dimensional real-time monitored data; performing grout diffusion path prediction based on the three-dimensional geologic model, and generating an initial grouting scheme through the predicted grout diffusion path; the fractal dimension is optimized according to a genetic algorithm, the grouting parameters are dynamically corrected through the optimized fractal dimension, and a grout diffusion result is obtained; establishing a multi-field coupling equation based on the slurry diffusion result, and optimizing the initial grouting scheme through the multi-field coupling equation to obtain an optimal grouting scheme; and according to the optimal grouting scheme, power pressure compensation is conducted, and grouting control is conducted. The problem that slurry diffusion is difficult to accurately control is solved.

The invention provides a numerical calculation method for double-explosion-source underwater explosion impact cavitation loads, and belongs to the technical field of computer data processing-based explosion impact wave calculation, and the method comprises the following steps: solving a propagation process of far-field underwater double-explosion-source explosion impact waves in a two-dimensional acoustic flow field by using a local discontinuous Galerkin (LDG) method; and the cavitation characteristics of the flow field under the action of the double-explosion-source underwater explosion shock waves are researched. A flow field dynamic pressure result calculated by the method is compared with a result calculated by an acoustic finite element method. The result shows that the flow field dynamic pressure result calculated by the method is well matched with the calculation result data of the acoustic finite element method, and the effectiveness and the accuracy of the method are verified.

The invention belongs to the technical field of ship bearings, and particularly relates to a ship bearing radial loading test bench and method for simulating ice load and water immersion working conditions, and the method comprises the steps: installing a to-be-tested intermediate bearing on a test platform, enabling the intermediate bearing to sleeve a test shaft, starting a cooling water circulation system to control the flow, cooling water enters a cooling water coil pipe to establish oil pool cooling circulation; a driving motor is started; a test shaft stably operates through equipment such as a reduction gearbox and the like; a dynamic pressure lubrication state is established, a radial dynamic load or a stable constant load is applied through a hydraulic loading system to simulate an icebreaking load working condition, and a simulated water body is injected into a water tank; the test conditions of the intermediate bearing in a ship immersion environment are constructed through water pressure adjustment, the temperatures of lubricating oil, a bearing bush and cooling water are monitored in real time, the loading force is adjusted through feedback data, and the performance of the intermediate bearing is judged after the test is finished. The problems that ice excitation and soaking environment simulation are insufficient and a loading structure is eccentric in the prior art are solved, and high-precision cooling and thermal stability evaluation are achieved.

The invention relates to the technical field of monitoring, in particular to a method and system for detecting and evaluating the corrosion risk of an offshore wind power steel structure. The method comprises the following steps: acquiring corrosion environment parameters and corrosion response parameters of a corrosion area in the offshore wind power steel structure; according to the corrosion environment parameters and the corrosion response parameters, the real-time corrosion rate of the corrosion area is determined; determining a local stress concentration factor of the corrosion area according to the three-dimensional scanning characteristics of corrosion deposits in the corrosion area; the dynamic pressure parameters of the marine environment serve as dynamic boundary conditions, the real-time corrosion rate and the local stress concentration factor serve as the basis, and the structural rigidity degradation amount of the steel structure in the corrosion area is determined through finite element iteration; according to the structural rigidity degradation amount, the structural safety coefficient of the steel structure in the corrosion area is determined; and determining the corrosion risk of the steel structure in the corrosion area according to the dynamic pressure fluctuation range of the marine environment and the structure safety coefficient of the steel structure in the corrosion area.

An annular sliding component is one of two sliding rings that rotate relative to each other and partition a sealed fluid space and a leakage space, the sliding component includes a dynamic pressure generating groove that generates a dynamic pressure, and includes an inclined groove which extends from the leakage space toward the sealed fluid space with an inclination in a forward rotation direction and has a first dynamic pressure generating end portion and a reverse groove which extends from a backward rotation direction side of the inclined groove in a backward rotation direction and has a second dynamic pressure generating end portion.

There is provided a sliding component that supplies a sealed fluid to a leakage side in a gap between sliding surfaces to exhibit high lubricity and has a small leakage of the sealed fluid. A sliding component that has an annular shape and is disposed in a place where relative rotation is performed in a rotary machine, includes a plurality of dynamic pressure generating mechanisms provided in a sliding surface of the sliding component, each of the dynamic pressure generating mechanisms including a deep groove portion that communicates with a leakage side, and a plurality of shallow groove portions that communicate with the deep groove portion and are arranged in a circumferential direction in parallel relationship to each other.

The invention discloses a pneumatic joint sealing performance intelligent test method and system based on dynamic pressure spectrum and multi-parameter fusion, and belongs to the technical field of pneumatic element sealing detection. According to the method, a dynamic pressure spectrum simulating an actual working condition is applied to a tested joint, pressure, temperature and ultrasonic signals are synchronously acquired, environmental thermodynamic interference is eliminated by adopting a temperature real-time compensation algorithm, and pressure change purely caused by leakage is separated by deducting system baseline data; and finally, fusing double characteristic parameters of the pressure leakage rate and the ultrasonic energy, and comprehensively evaluating the sealing performance through an intelligent judgment model. The system comprises a gas circuit tool module, a multi-sensing module and a control processing module, can effectively solve the problems that a traditional static pressure maintaining method is greatly influenced by temperature, transient leakage cannot be detected and the like, has the advantages of being high in detection precision, high in anti-interference capability, capable of simulating real working conditions and the like, and remarkably improves the test reliability and efficiency.

A worm and worm gear pair heat-fluid-solid coupling analysis method comprises the following steps that 1, a heat-fluid-solid coupling simulation analysis model of a worm and worm gear pair is built, and a three-dimensional geometric model is built based on the worm and worm gear meshing principle; 2, parameterized grid division is carried out on the simulation analysis model, a tetrahedral unstructured grid is adopted for a fluid domain, and a worm and worm gear tooth surface area is densified; 3, based on the fluid dynamics theory and an RNG # imgabs0 # turbulence model, establishing an oil-immersed lubricating oil gas two-phase flow transient simulation model, and solving fluid dynamic pressure and a convective heat transfer coefficient through a pressure-speed coupling algorithm; 4, establishing a three-dimensional transient dynamic simulation model based on a solid mechanics theory, combining a temperature-stress coupling field equation, adopting an explicit dynamic algorithm, and iteratively solving thermal deformation and stress strain of the worm and the worm gear through a finite element method; and 5, bidirectionally transmitting the pressure of the fluid domain, the convective heat transfer coefficient and the thermal deformation data of the solid domain through the fluid-solid interface, and carrying out iterative solution until convergence.

The invention discloses a gas leakage process dynamic parameter-based limited space combustion explosion consequence prediction method. The method comprises the following steps of: acquiring concentration and speed segmentation time sequence data in every delta t time period from gas leakage in each working condition; forming a three-dimensional primary ignition source array, and simplifying the ignition source array according to a blasting numerical simulation result; obtaining a maximum temperature field data set, a static pressure field data set and a dynamic pressure field data set on a typical section in the burning and explosion process; mapping the concentration and speed segmented time sequence data set to a maximum temperature field, static pressure field and dynamic pressure field data set to obtain a combustible gas leakage explosion result prediction data set, preliminarily establishing a combustion explosion result prediction model, and training; and collecting gas leakage concentration and speed time sequence data in the limited space, and inputting the data into the combustion explosion consequence prediction model to obtain a temperature, static pressure and dynamic pressure maximum value field in the combustion explosion process. According to the invention, automatic prediction of the maximum overpressure, the dynamic pressure and the temperature field in the explosion process after combustible gas leakage in a real-time or super-real-time limited space is realized, and the prediction result is accurate.

The invention relates to the technical field of gas bearings, in particular to a refrigerant foil dynamic pressure gas radial bearing capacity estimation method and system.The method comprises the steps that the working temperature, the working pressure, the bearing diameter and the rotating speed when a bearing works are obtained, and a refrigerant medium is determined; obtaining the dynamic viscosity of the refrigerant according to the working temperature, the working pressure and the refrigerant medium; according to the bearing diameter, the rotating speed, the refrigerant dynamic viscosity and the main structure parameters of the bearing, a bearing capacity estimation formula of the bearing is constructed; performing iterative optimization on the main structure parameters of the bearing according to a bearing capacity estimation formula of the bearing to obtain optimal structure parameters; the main structure parameters of the bearing subjected to iterative optimization comprise the bearing length, the bearing nominal clearance and the eccentricity rate. According to the method, the bearing capacity of the bearing is estimated by selecting different bearing lengths, bearing nominal clearances and eccentricity ratio combinations, so that main structural parameters of the bearing are designed, the bearing capacity of the bearing meets the requirements, and the running eccentricity ratio is within a reasonable range.

There are provided sliding components that allow sliding surfaces to smoothly slide against each other regardless of whether a relative rotation direction is a forward rotation or a reverse rotation. The sliding components and include: a pair of sliding surfaces and disposed to face each other at a location where a relative rotation takes place when a rotating machine is driven. The sliding surface is provided with a first dynamic pressure generating groove communicating with a radially outer-side space and extending in one circumferential direction, a second dynamic pressure generating groove extending in the opposed circumferential direction, and a conduit groove communicating with the space. The conduit groove includes an annular groove and a communication groove communicating between the annular groove and the space. The second dynamic pressure generating groove is disposed closer to the space than the annular groove, and communicates with the annular groove.

The invention relates to a dynamic and static pressure mixed gas radial bearing, and belongs to the technical field of air bearings. The shaft sleeve is sleeved with the bearing seat, a limiting part is arranged outside the shaft sleeve, and a limiting groove is correspondingly formed in the inner wall of the bearing seat; in the radial direction, the bump foil assemblies are arranged between the shaft sleeve and the bearing seat, and in the circumferential direction, the bump foil assemblies are arranged between the limiting parts at intervals; a plurality of first air inlet holes are formed in the bottom of the limiting groove, a plurality of second air inlet holes are formed in the limiting part, and the first air inlet holes correspond to the second air inlet holes in position. According to the design, the integrity of the bump foil assembly can be guaranteed, the structure is simple, machining is convenient, and mounting and dismounting are more convenient. When the speed of the rotor is low, the static pressure gas forms a gas film, and the bearing capacity of the dynamic and static pressure mixed gas radial bearing is enhanced. When the rotating speed of the rotor is high, dynamic pressure can be generated on the basis of static pressure, and the dynamic pressure and static pressure mixed gas radial bearing has larger bearing capacity due to superposition of the dynamic pressure and the static pressure.

The utility model belongs to the technical field of high-temperature flow field pressure testing, and discloses a water-cooling pressure probe for measuring a turbine interstage three-dimensional dynamic high-temperature flow field, which is characterized by comprising a probe head, a support rod, a mounting seat and a lock cover. The probe head comprises a cylinder and a cylinder beveled body which share the same bottom surface, and two dynamic pressure sensors are packaged in the probe head. The diagonal plane of the cylindrical beveling body and the side face of the cylinder are each provided with a pressure sensing hole, and the pressure sensing holes are communicated with a pressure sensor. A plug board with a vortex generating device is arranged in the probe head and the support rod, so that heat convection between cooling water and the pressure measuring channel is enhanced. Three-dimensional flow parameters such as a pitch angle, a deflection angle, total pressure, static pressure and Mach number in a turbine interstage flow field can be measured through calibration of a calibration wind tunnel. Compared with an existing probe, the probe can realize flow field measurement in a high-temperature environment, prevents a sensor at the head of the probe from temperature drift and even damage due to heating, and further ensures the accuracy of measured data.

The invention discloses a pressure adjusting method and system for a pressure air gun for drying, and relates to the technical field of pressure air gun adjusting.The method comprises the steps that pressure distribution data and drying effect parameters of the surface of a dried object are collected in real time; the drying effect parameters are input into a reinforcement learning and quantum annealing collaborative decision model, a dynamic pressure adjusting strategy is generated, and the dynamic pressure adjusting strategy comprises control parameters of a pressure value, a waveform frequency and a nozzle direction; an air gun is controlled to output a target pressure waveform according to the dynamic pressure adjusting strategy, the target pressure waveform is generated based on the 3D geometrical characteristics of the drying object, and the impedance of an internal flow channel of the air gun is adjusted in real time through a magnetorheological fluid strategy; in the drying process, three-section mode switching is triggered according to the real-time water content and surface roughness data, chaos frequency modulation pulse waves are output in the initial stage to peel off water, fractal diffusion waves are switched in the middle stage to achieve uniform coverage, and nanometer resonance waves are adopted in the final stage to complete drying.

The invention relates to the technical field of water source heat pump adjustment, and discloses a dynamic pressure difference compensation system and method for a heat supply network, and the method comprises the following steps: obtaining a topological structure and a flow-pressure difference curve of each main pipeline in the heat supply network; establishing a thermal inertia model for each main pipeline; generating a fuzzy rule base of the main pipeline based on the topological structure, the flow-pressure difference curve and a thermal inertia model; determining control parameters of a main pipeline based on the fuzzy rule base; the actual pressure difference and the target pressure difference of the main pipeline are obtained; based on the actual pressure difference, the target pressure difference and the control parameters, the flow adjusting amount of the main pipeline is calculated; adjusting a water pump and a valve of a heat supply pipe network based on the flow adjusting quantity; according to the method, the problem of the heat supply network in the aspect of dynamic pressure difference compensation is solved, and quick response and energy consumption control of pressure difference compensation are both considered.

The invention provides a labyrinth sealing structure, and belongs to the technical field of gas turbine and engine sealing, the labyrinth sealing structure specifically comprises a labyrinth disc and a sealing ring, a rotor assembly and the labyrinth disc are coaxial and fixedly connected, a plurality of labyrinth teeth protruding towards a stator assembly are arranged on the peripheral side face of the labyrinth disc, the sealing ring is arranged between any two adjacent labyrinth teeth in a sleeving mode, and the labyrinth teeth are arranged in the labyrinth disc. The sealing ring is of a hollow and internally-closed structure, when the rotating speed of the rotor assembly is smaller than or equal to the first rotating speed, the sealing ring abuts against the labyrinth and the stator assembly, and a gap between the labyrinth and the stator assembly is sealed through the sealing ring; when the rotating speed of the rotor assembly is larger than the first rotating speed, dynamic pressure sealing is formed between the labyrinth and the stator assembly through the pressure difference of the air inlet side and the air outlet side of the labyrinth, the side, facing the stator assembly, of the sealing ring is sunken towards the interior of the sealing ring, and the sealing ring is separated from the stator assembly. According to the treatment scheme, the service life of the labyrinth sealing structure is prolonged.

A rotary mechanical shaft end fluid pressure adjusting device comprises a circular ring and axial flow guide grooves, the axial flow guide grooves are evenly distributed in the inner surface of the circular ring in the circumferential direction, the groove shapes are logarithmic spiral lines or parabolas or involutes, and the number of the axial flow guide grooves is 30-120. The circular ring is used for being fixed to the inner surface of the stator, and a radial gap is formed between the circular ring and the rotor. According to the invention, the pressure of the flowing fluid at the shaft end can be reduced or increased in the axial direction, the adjusted pressure can further meet the performance requirements of subsequent sealing or other parts, and the function completeness and stability of the whole machine are guaranteed.

The utility model relates to a dynamic and static pressure mixed thrust bearing structure which comprises a back plate, the back plate is of a hollow cylinder structure, a plurality of fan-shaped bosses are evenly distributed on the front face of the back plate at intervals in the circumferential direction, a gasket and a bottom foil are arranged between every two adjacent fan-shaped bosses, fan-shaped flat foils are arranged on the gaskets and the bottom foils, and pressure equalizing grooves are formed in the fan-shaped bosses. The pressure equalizing groove is an arc-shaped groove, air outlet holes are formed in the pressure equalizing groove, the air outlet holes are connected with air inlet holes through air supply flow channels, the air supply flow channels are located in the back plate, and the air inlet holes are located in the outer wall of the back plate. The dynamic and static pressure hybrid bearing provided by the utility model is of a multi-tile structure, and the flexible foils and the steps with the air inlet holes are distributed in a staggered manner. The working back pressure of the bearing can be improved through external high-pressure air supply of the air inlet holes, the dynamic pressure effect is improved, abrasion of the bearing during starting and stopping is avoided, and therefore the bearing capacity and rigidity of the bearing are improved.

The utility model relates to a whirlwind type oil separator which comprises a cylinder body, an air inlet pipe, an air outlet pipe, an upper partition plate and a lower partition plate, the upper partition plate and the lower partition plate are arranged in the cylinder body, the upper partition plate divides the interior of the cylinder body into a diffusion section and an oil subsection, and the diffusion section on the upper portion is communicated with the oil subsection on the lower portion through an air rising pipe. The lower partition plate divides the oil section into an upper separation section and a lower oil groove section, the air inlet pipe is communicated with the separation section, the air outlet pipe is communicated with the diffusion section, and the diffusion section is provided with diffusion blades. On the premise that the oil separation efficiency is guaranteed, the pressure loss of cyclone type oil separation is reduced by recovering dynamic pressure, and then the pressure ratio of a compressor is reduced, so that the energy efficiency of a refrigerating system is improved.

A water gun is provided. On the water gun, when a liquid pump is turned on, liquid in a liquid storage device is injected into a first water tank through a water inlet hole. The liquid pump is used as a unique power source to synchronously perform two functions: In a first function, the liquid in the first water tank is extracted through the water outlet hole for being pressurized, thus forming a high-pressure jet water flow. In a second function, a dynamic pressure field is built inside the first water tank to force a part of the liquid to flow towards a second water tank through a water replenishment hole. The single-pump double-output design directly replaces a shooting water pump and a mist spray water pump that work independently in a traditional double-pump system, and fundamentally reduces power consumption.

The invention provides a compressor intelligent control method and system based on dynamic pressure relief and a storage medium, and the method comprises the steps: firstly, capturing the multi-physical field coupling characteristics of a compressor in a shutdown state in real time by deploying a pressure, temperature, vibration and current four-dimensional sensing network; secondly, based on a preset pressure entropy model, fusing the pressure fluctuation intensity, the temperature anomaly index, the high-frequency vibration factor and the current attenuation coefficient to quantitatively evaluate a pressure entropy value, and triggering a three-stage pressure relief mode based on the pressure entropy value; then, based on the deviation between the cavity pressure and the target pressure, pressure relief parameters are dynamically adjusted, and stable pressure transition is achieved; and finally, collecting full-link data of pressure relief operation, and dynamically optimizing pressure entropy model parameters based on reinforcement learning, so that the system continuously adapts to equipment aging and working condition changes. Through dynamic closed-loop adjustment, pressure relief energy consumption waste and equipment loss are reduced, and the stability of the pressure relief process is improved.

The invention relates to the technical field of electromagnetic valves, in particular to an air pump electromagnetic valve capable of adaptively adjusting displacement, which comprises a valve seat, an electromagnet, an adjusting rod, a valve core and a movable piece, the interior of the valve seat is divided into an outer cavity and an inner cavity, a first communication port is arranged between the outer cavity and the inner cavity, and the movable piece in transmission connection with the valve core is arranged in the inner cavity; the valve element is connected with an adjusting rod in the electromagnet valve element through an elastic assembly, and by adjusting the installation height of the adjusting rod in the armature, it can be ensured that when the valve element is located at the preset position, the second communication opening and the first communication opening in the movable part are mutually staggered, and a throttling opening with the normal opening degree is formed; the valve element drives the movable part to move up and down, and the opening degree of the throttling opening is dynamically adjusted, so that the air outlet pressure is adaptively controlled according to the air inlet pressure, the air outlet pressure is stabilized within the set range, the problem that a traditional electromagnetic valve is difficult to respond to dynamic pressure changes is effectively solved, and constant adjustment of the outlet pressure is achieved.

The invention belongs to the technical field of aero-engine design, and provides a sliding bearing lubrication gap prediction method based on a PINN neural network, and the method comprises the steps: generating a training data set of the PINN neural network, constructing the PINN neural network, employing a reverse mechanism of the neural network, calculating a partial differential operator through automatic differential, and carrying out the prediction of the lubrication gap of a sliding bearing. Customizing a dynamic pressure lubrication Reynolds equation into a loss function in a deep learning framework; and a prediction data set of the neural network model is generated, the trained PINN model and weight parameters are loaded, construction of a prediction model is completed, and an oil film pressure distribution curved surface is generated. According to the method, the accuracy of oil film pressure distribution calculation is remarkably improved, and meanwhile, the speed of numerical calculation can be remarkably increased.

The invention discloses a flow demand control method and device for electric engineering machinery, and the method comprises the steps: determining a pilot handle opening value according to a pilot handle opening voltage value; according to the pilot handle opening value and a preset hydraulic oil demand response characteristic value, a hydraulic oil demand flow value is obtained; a main pump pressure value is obtained, the hydraulic oil demand flow value is dynamically corrected according to the main pump pressure value, and a corrected flow value is obtained; and the current of the first proportional valve is adjusted according to the corrected flow value, and the opening value of the first proportional valve is controlled. The flow demand is corrected in real time through the main pump pressure, high-pressure working condition overpower output is avoided, the overflow frequency is reduced, and dynamic pressure correction is achieved.

The embodiment of the invention discloses an aircraft control method and device, electronic equipment and a storage medium, and relates to the technical field of aircrafts, and the method comprises the steps: determining the actual overload of an aircraft at the current moment; generating a guidance instruction according to the actual overload of the aircraft at the current moment; adjusting the actual dynamic pressure of the aircraft at the current moment according to the guidance instruction; wherein the adjusted actual dynamic pressure of the aircraft at the current moment is the same as the dynamic pressure of the standard trajectory of the aircraft at the current moment. According to the embodiment of the invention, the method can effectively reduce the impact on the guidance precision of the aircraft when the aerodynamic parameters change in a large range, improves the tracking precision of the aircraft on a standard trajectory, and reduces the flight trajectory deviation of the aircraft.

The invention relates to the field of guide bearing bush control, in particular to a signal processing system and method for guide bearing bush clearance automatic adjustment, and the system comprises a clearance metering module, a model boundary module, a fault learning module, a clearance adjustment module and an oil film lubrication module, the model boundary module is used for establishing a dynamic pressure lubrication model of the guide bearing bush and solving the gap of the guide bearing bush, the fault learning module is used for determining the gap adjustment amount, the gap adjustment module is used for adjusting gap distribution, and the oil film lubrication module is used for adjusting lubricating oil injection. And fault identification and automatic fault-tolerant adjustment are carried out, so that mechanical vibration of the bearing is reduced, operation stability of equipment is guaranteed, abnormal bearing bush gaps are avoided, mechanical efficiency of the bearing is improved, invalid power loss is reduced, service life of the equipment is prolonged, thickness and pressure distribution of a lubricating oil film are improved, and performance of bearing turbine equipment is improved.

The invention discloses a wind turbine airfoil full-attack-angle pneumatic measurement and prediction method for a wind tunnel experiment in the field of wind tunnel experiments, and the method comprises the steps: 1) carrying out the modeling of a wind turbine airfoil, designing a wind turbine airfoil model of the wind tunnel experiment, and building a test platform; (2) checking the safety of equipment and an experimental environment; 3) opening a wind tunnel to obtain a set wind speed; 4) sequentially changing the attack angle, obtaining the pressure data of the wind turbine airfoil at the expected attack angle moment, and closing the wind tunnel after the measurement is finished; 5) adjusting the pitot tube to be right in front of the wind turbine airfoil, repeating the step 3), and collecting incoming flow pressure right in front of the wind turbine airfoil when the attack angles are 90 degrees and 270 degrees; (6) data processing is conducted, and correction coefficients related to the incoming flow wind speed are obtained; and 7) calculating a lift coefficient and a resistance coefficient, obtaining a resistance coefficient shrinkage ratio, and predicting the lift coefficient and the resistance coefficient of the wind turbine airfoil under the full-attack-angle working condition. The method can quickly predict the aerodynamic change condition of the wind turbine airfoil under the expected working condition.

The utility model discloses a diffusion type exhaust passage structure of double-screw gas conveying equipment, which mainly comprises an air cylinder and an axial exhaust pipe arranged on the air cylinder, and the diffusion type exhaust passage structure of the double-screw gas conveying equipment comprises the specially designed axial exhaust pipe. The direction of the airflow in the pipeline is basically consistent with that of the airflow from the compression cavity, so that mechanical loss caused by rapid turning of the airflow in a traditional structure can be avoided. A guide plate device is specially designed at an inlet of the axial exhaust pipe. Air flow from the compression cavity directly flows into the gaps of the guide plates and moves forwards along the guide plates, and energy loss caused by air turbulence in a traditional structure can be reduced. A plurality of diffusion areas are formed at the inlet of the exhaust pipe by utilizing the guide plate and the inner wall of the pipeline, and the dynamic pressure of high-speed airflow from the compression cavity is converted into static pressure by utilizing the diffusion areas, so that the pressure is increased while the speed is reduced, and the energy loss caused by the high-speed airflow is avoided.

The invention relates to the technical field of automatic control theory application and data center thermal management, and discloses a data center emergency refrigeration control method based on state space model prediction, which comprises the following steps: establishing a thermodynamic cycle state space equation; the refrigeration flow set value change rate and the water return side pressure change amount are obtained, and the dynamic heat exchange sensitivity is determined; monitoring feedback current characteristics of the driving unit, inverting cooling path resistance distribution and updating gain matrix elements; calculating a state prediction information sequence according to the temperature vector prediction deviation, and adjusting a time domain step length; the dynamic heat exchange sensitivity is introduced into prediction logic, controlled variable dynamic pressure retardation is compensated, an emergency refrigeration frequency control instruction is output, fluid fluctuation is converted into sensitivity compensation of a logic level, non-linear dynamic pressure damping of the emergency working condition is effectively impacted, the problems of control overshoot and logic instability caused by physical lag are solved, and the reliability of the system is improved. And the refrigeration response precision at the emergency conversion moment is improved.