91 results about "Ideal gas" patented technology

The invention belongs to the field of target detection, particularly relates to a bubble detection method based on multi-modal input and an improved target detection network, and aims to solve the problems that an existing bubble detection model is sensitive to environmental parameter changes, depends on a large amount of annotated data, is poor in migration adaptability, lacks multi-modal information fusion and physical law constraints, and is poor in migration efficiency. The precision is low and the cost is high. According to the method, gas-liquid two-phase flow images and temperature, pressure and flow velocity parameters are collected, a target detection network is constructed, and multi-scale visual features are extracted. After physical parameters are coded into high-dimensional features, a comprehensive feature map is generated through dynamic weighted fusion, and a detection head is input to output a bounding box and convert the bounding box into an actual size. An ideal gas equation and fluid mechanics are adopted to construct a physical constraint loss function correction size, environment self-adaption is achieved in combination with a dynamic weight adjustment and fine adjustment mechanism, and the detection precision and physical consistency are improved. According to the method, the bubble detection precision and the environmental adaptability are improved, and the labeling cost is reduced.

The invention relates to the technical field of safety monitoring, and discloses a linkage monitoring method and system for a gas leakage alarm and a gas meter, and the method comprises the steps: periodically regulating and controlling the temperature of a gas sensor, obtaining monitoring values at different temperatures, calculating a specific value, and recognizing gas leakage and non-leakage gas sources; when leakage is judged, activating a camera to shoot an image of a gas meter counter, synchronously acquiring temperature and pressure data, and uploading the temperature and pressure data to a data processing center; a gas consumption value is extracted based on an image recognition algorithm, environmental interference is corrected in combination with an ideal gas state equation and a dynamic compensation model, and high-precision gas consumption is generated; and by analyzing the time sequence relevance between the corrected consumption and the leakage signal, if an abnormal condition is met, the valve is automatically closed, and an alarm is given. According to the invention, high precision, low false alarm and quick response of gas leakage detection can be realized.

The invention discloses a continuous equipment temperature distribution optimization control method and system, and belongs to the technical field of temperature control, and the method specifically comprises the steps: monitoring equipment production process parameters in real time, and transmitting the parameters to a control center; the control center corrects the parameters by using a compensation algorithm constructed based on an ideal gas state equation, extracts furnace temperature data from the corrected parameters, calculates a control signal according to the deviation between the furnace temperature data and a preset furnace temperature target value by adopting PID (Proportion Integration Differentiation) operation, and adjusts the opening degree of a gas actuator to obtain a corrected gas flow value; calculating required combustion-supporting air flow according to the value and a preset air-fuel ratio, and adjusting a combustion-supporting air actuator to stabilize heat supply in the furnace; when the furnace temperature is stable, an online temperature measurement thermal imager is used for collecting the temperatures of five point positions of the pipe body, the average value is calculated and compared with the temperature required by the process, and then the left and right temperature adjustment areas are adjusted; the method can effectively improve the stability of equipment production and the product quality.

The invention discloses a natural gas-diesel oil injection switching control system of a dual-fuel diesel engine, which relates to the technical field of automatic control and comprises a data acquisition monitoring module, a fuel analysis module, a prediction control module, a control optimization module and a switching protection module. Engine operation parameter data are collected in real time through an engine sensor interface and preprocessed, and fuel dynamic proportion analysis is carried out according to different rotating speeds and load intervals of an engine by taking a preset proportion as an initial reference datum and applying an intelligent algorithm; the engine can obtain the most appropriate natural gas and diesel oil mixing proportion under various working conditions, according to an ideal gas state equation, based on pressure and temperature data, monitored in real time, in a gas supply pipeline, dynamic compensation is conducted on the gas volume flow, real-time gas supply energy is calculated, the gas supply amount can be accurately controlled in the mode, and the gas supply efficiency is improved. It is guaranteed that the engine obtains stable and accurate energy supply, and therefore stable operation of the engine is maintained.

The invention provides a method for simulating the influence of montmorillonite clay mineral water on organic matter pyrolysis hydrocarbon generation, and belongs to the technical field of organic matter pyrolysis. The method comprises the following steps: heating montmorillonite to obtain dehydrated montmorillonite, mixing organic matters and the dehydrated montmorillonite in an argon atmosphere and a dry environment, transferring a mixed sample into a gold tube, and loading the sample; putting the gold tube into an iron reaction kettle, filling the reaction kettle with water, and cooling after heating reaction; putting the cooled gold tube into a gas collecting device, and calculating the amount of substance of gas according to an ideal gas state equation; the collected gas is subjected to GC analysis to obtain the percentage of each gas, the yield of each gas is calculated by combining the amount of substance of the gas, and the influence of the montmorillonite clay endogenous water on hydrocarbon generation by thermal decomposition of organic matters is evaluated. Under the condition that only the unified boundary condition of clay mineral water is changed, a verifiable judgment system of'endogenous water type-product spectrum characteristic-reaction channel 'is established for the first time.

The application discloses an air dynamic test platform vacuum equipment leakage fault diagnosis method and system, aiming at solving the problems that the existing method is difficult to adapt to the complex time-varying characteristics of mixed gas, data is sparse, and lack of interpretability. The method first collects time series pressure data through a conventional pressure sensor, uses the ideal gas state equation as a physical mechanism model, deduces a leakage rate calculation equation, and extracts key characteristics of instantaneous leakage rate and cumulative leakage rate; then a BP neural network is constructed as a data-driven model, taking the leakage rate as input, and outputting normal and abnormal judgments after training with historical data. The application innovatively integrates physical mechanism and machine learning, without the need for special detection equipment, ensuring the interpretability of the diagnosis results, improving the diagnosis accuracy and reliability under small sample and variable working conditions, and realizing high-precision, low-cost air tightness online monitoring and early warning.

The invention discloses a method and device for estimating residual waste gas in a cylinder of a hydrogen combustion range extender, a vehicle and a medium, and relates to the technical field of vehicle engines, and the method comprises the steps: building a waste gas flow model at an exhaust valve based on engine structure parameters, a pressure signal and a temperature signal of an exhaust manifold, and exhaust efficiency; on the basis of the inlet waste gas flow of the exhaust manifold and the outlet waste gas flow of the exhaust manifold, according to the mass conservation relation and the ideal gas state equation, an exhaust pressure average value discrete dynamic model of the exhaust manifold is built; constructing a self-adaptive observer based on an exhaust pressure average discrete dynamic model, and estimating the exhaust efficiency; according to the online estimation result of the exhaust efficiency, the mass of exhaust gas exhausted in each cycle is obtained, and the amount of residual exhaust gas in the cylinder is calculated. By adopting the method, the mass of exhaust gas in each cycle and the amount of residual exhaust gas in the cylinder can be accurately estimated in real time in the actual vehicle running process, so that reliable reference is provided for combustion control and emission optimization.

The invention provides an escaping carbon source emission monitoring method and system and a medium, and belongs to the technical field of carbon emission monitoring. The method comprises the steps that a pressure sensor is installed on the side, close to an indoor unit, in a refrigerant pipe connecting the indoor unit and an outdoor unit of refrigeration equipment, and a temperature sensor is installed in the refrigerant pipe of the indoor unit; when the refrigeration equipment is in a stable operation working condition and the external environment condition is constant, temperature regulation and control are started, the temperature of a refrigerant in a refrigerant pipe of an indoor unit is regulated and controlled and stabilized at a preset temperature, real-time pressure data collected by a pressure sensor are obtained, smooth filtering processing is carried out, and an average pressure value is obtained; and a pressure and medium quantity relation model is established based on the ideal gas state equation, the refrigerant dissipation amount is calculated by combining the initial pressure value and the initial refrigerant mass in the refrigerant pipe obtained during initial filling and the calculated average pressure value, and then the refrigerant dissipation amount is pushed to an enterprise carbon management platform. According to the invention, the sensor layout and algorithm are optimized, refrigerant dissipation is accurately monitored, and carbon emission accounting is realized.

The invention belongs to the field of marine seismic exploration, and particularly relates to a non-ideal gas gun wavelet simulation method based on a unified bubble theory, which comprises the following steps: acquiring sea environment parameters; designing air gun working parameters and an air gun array; calculating the bubble radius, the bubble volume, the bubble pressure, the bubble heat loss rate, the gas release rate, the bubble volume change rate and the bubble temperature change rate at each moment according to the sea area environment parameters, the air gun working parameters and the air gun array; and calculating a pressure signal generated at any point in the seawater by bubble oscillation at each moment. According to the method, a non-ideal gas thermodynamic state equation is introduced on the basis of a traditional bubble dynamic model, and an evolution mechanism of the whole process of generation, expansion, contraction and the like of bubbles is considered in a unified manner on the basis of a unified bubble theory, so that sound wave wavelet signals generated by an air gun in an actual working environment are simulated more accurately; and the accuracy and adaptability of neutron wave modeling and inversion in seismic exploration are improved.

The invention provides an energy storage container pressure building and energy storage stage volume linear variable process modeling and simulation method. The method comprises the steps that a pressure-time mathematical model in a container in the energy storage process of a hydraulic compressed air system is established; initial pressure building and energy storage are divided into four sub-steps, liquid is alternately pumped into two acting containers, pressurized gas is pushed to enter an energy storage container, and multiple times of inflation are completed in a circulating mode; based on 12 thermodynamic assumptions (such as temperature uniformity, ideal gas state, quasi-steady state process and the like), deriving functions of pressure and gas volume changing along with time; and a pressure change curve is obtained through simulation calculation. According to the method, the dynamic characteristics of the energy storage process can be accurately described, the change relation between physical quantities is reflected, a theoretical basis is provided for system working condition analysis, parameter matching and optimization design, meanwhile, an ideal mathematical model is established by simplifying coupling factors, and a target is provided for calculation of the maximum energy storage capacity of the system.

The application provides a dynamic measurement method and system based on parallel differential pressure analysis, and relates to the technical field of gas-liquid mass transfer measurement. The method adopts a measurement unit and a control unit in parallel, a first closed container of the measurement unit containing liquid and gas, and the initial volume of the gas phase in a second closed container of the control unit being the same as the volume of the gas in the first closed container. After the pressure of the two containers is synchronously and suddenly increased to the initial pressure P0 by synchronous pressure excitation, the system is closed, and the pressure decay curves P1(t) and P2(t) in the two containers are synchronously collected. After differential processing, the influence of system leakage is eliminated, and the net pressure decay curve ΔP(t) is obtained. Based on the ideal gas state equation, the change amount of the dissolved gas mass with time is inversed, and the dissolution kinetics data are obtained. The application can dynamically and accurately measure the gas dissolution process, effectively eliminates the leakage interference, and provides key dissolution kinetics data for gas-liquid mass transfer engineering.

The invention provides an energy storage container pressure building and energy storage stage constant power isothermal process modeling and simulation method, which comprises the following steps of: firstly, building a dynamic mathematical model of an energy storage process of a hydraulic compressed air system, and circularly executing an initial pressure building and energy storage stage by dividing the initial pressure building and energy storage stage into four sub-steps; the compressed gas enters the energy storage container, and meanwhile liquid backflow is completed. Modeling is based on six assumed conditions including an isothermal process, an ideal gas state equation and the like, and a function relation between pressure and gas volume changing along with time is deduced. A dynamic curve of the pressure changing along with time can be obtained through simulation calculation. The method can accurately describe the dynamic characteristics of each physical quantity in the energy storage process, provides a theoretical basis for system working condition analysis, parameter matching and optimization design, simplifies complex coupling factors, and establishes a maximum energy storage capacity mathematical model under ideal conditions.

The invention discloses a method for measuring the gas content in a die casting, and belongs to the technical field of material detection. The method comprises the following steps: loading a sample into the closed desorption cavity; vacuumizing and pre-degassing the cavity by using an oil-free high-vacuum acquisition module formed by connecting a molecular pump and a dry-type screw pump in series; stepwise heating is carried out on the sample through program temperature control; the released gas is guided into a differential pressure sensing metering unit through a low-thermal-conductivity aluminum oxide ceramic isolation tube; the unit comprises a reference cavity and a measuring cavity which are arranged in the same constant temperature device, and the gas inflow rate is dynamically represented by measuring the pressure difference between the two cavities; and based on the ideal gas state equation and a calculation model containing cavity thermal expansion compensation, calculating the amount of the gas substance in unit time in real time. The problems of poor precision and repeatability caused by oil pollution, thermal interference and discontinuous metering are solved, and continuous, dynamic and high-repeatability automatic measurement of the gas content in the die casting is realized.

The invention provides a modeling and simulation method for a pressure linear isothermal process in a pressure building and energy storage stage of an energy storage container. The modeling and simulation method comprises the following steps: establishing a pressure-time mathematical model in the container in an energy storage process of a hydraulic compressed air system; an initial pressure building and energy storage stage is divided into four sub-steps, and multi-cycle compression and transfer of gas are achieved by alternately using two acting containers; based on six idealized assumptions (including an isothermal process, an ideal gas state equation and the like), a thermodynamic law is combined to derive functions of pressure and gas volume changing along with time; and finally, a pressure-time change curve is obtained through simulation calculation. According to the method, the dynamic characteristics of the energy storage process can be accurately described, the dynamic relation between physical quantities can be revealed, a theoretical basis is provided for system working condition analysis, parameter matching and optimization design, meanwhile, a maximum energy storage capacity mathematical model under ideal conditions is established by simplifying coupling factors, and the method has important engineering application value.

The application belongs to the field of marine seismic exploration, and particularly relates to a non-ideal gas air gun wavelet simulation method based on a unified bubble theory, comprising: obtaining sea area environment parameters; designing air gun working parameters and an air gun array; according to the sea area environment parameters, the air gun working parameters and the air gun array, calculating the bubble radius, bubble volume, bubble pressure, bubble heat loss rate, gas release rate, bubble volume change rate and bubble temperature change rate at each moment; and calculating the pressure signal generated by bubble oscillation at any point in seawater at each moment. The application introduces a non-ideal gas thermodynamic state equation on the basis of a traditional bubble dynamics model, and considers the evolution mechanism of the whole process of bubble generation, expansion, contraction and the like based on the unified bubble theory, so that the sound wave wavelet signal generated by the air gun under the actual working environment is more accurately simulated, and the accuracy and adaptability of wavelet modeling and inversion in seismic exploration are improved.

The present invention discloses a safety early warning system, which relates to the field of early warning and control technology, including an acquisition and processing module, an analysis and prediction module and an early warning and control module; the acquisition and processing module measures temperature and pressure in the current cycle, combines the temperature and pressure of the historical cycle, and processes them into a standard data tensor; the analysis and prediction module establishes a matching degree matrix through dynamic time regularization, introduces physical regularity constraints in principal component analysis based on the ideal gas equation, extracts and generates a coupling feature sequence, splices it with the standard data tensor, and then inputs it into a prediction model, outputs the prediction data tensor and fits to generate a trend function of temperature and pressure; the early warning and control module dynamically determines the dangerous moment and dynamically determines the adjustable time, performs model predictive control based on the equipment control model, defines the control target function and solves the optimal control problem within a finite time, obtains the optimal parameter adjustment vector and executes control, and realizes accurate prediction and control considering the temperature, pressure coupling relationship and adjustable time.

The application discloses a continuous equipment temperature distribution optimization control method and system, and belongs to the technical field of temperature control, and specifically comprises the following steps: real-time monitoring of equipment production process parameters and transmission to a control center; the control center uses a compensation algorithm based on an ideal gas state equation to correct the parameters, extracts furnace temperature data from the corrected parameters, and uses PID operation to calculate a control signal according to the deviation of the furnace temperature data from a preset furnace temperature target value, adjusts the opening degree of a coal gas actuator to obtain a corrected coal gas flow value; then, according to the value and a preset air-fuel ratio, the required combustion-supporting air flow is calculated, and the combustion-supporting air actuator is adjusted to stabilize the heat supply in the furnace; when the furnace temperature is stable, an online temperature measurement thermal imager is used to collect the temperatures of five points on the pipe body, the average value is calculated and compared with the process requirement temperature, and then the left and right temperature adjustment zones are adjusted; the method can effectively improve the stability of equipment production and product quality.

The invention discloses a real-time monitoring and digital twinning method for a superplastic forming process, which relates to the field of superplastic forming, and is characterized in that the volume of gas in a thin-walled part in the superplastic forming process is calculated through theoretical analysis and integration of an ideal gas state equation, and a calculation result is output to a computer. A finite element simulation database is constructed, data calling is carried out, the superplastic deformation process of the thin-wall part can be displayed in real time, and superplastic forming digital twinning and real-time monitoring are achieved. The problem that the high temperature in the superplastic forming die cannot be monitored in a closed environment is solved. According to the invention, the ideal gas state equation is associated with the gas temperature, volume and pressure intensity, and the volume change caused by the change of the temperature and the pressure intensity is calculated through integration through the ideal gas state equation. The superplastic forming condition of the thin-wall part can be monitored in real time by calculating the volume of the gas in the plate in the superplastic forming process.

This invention discloses a PINN air shock wave capture method based on a Mach cone spatial causal bimatrix, belonging to the fields of aerodynamics, high-speed compressible air fluid simulation, and physical information neural networks. This method is designed for supersonic or transonic airflow fields. The physical information neural network outputs air density, velocity vector, and pressure, and obtains the total energy E and the physically permissible state through positive mapping and the ideal gas equation of state. Local air states and differentiable interface fluxes are constructed on the adjacent interfaces of sampling points, forming local conserved residuals of mass, momentum, and energy. Furthermore, a Mach cone spatial causal bimatrix is ​​constructed based on the local Mach number M, Mach cone half-angle, characteristic wave velocity sign, interface normal vector, and relative positions of adjacent points. The forward flux weight matrix is ​​applied to the residual contribution, and the backpropagation weight matrix is ​​applied to the gradient backpropagation, thereby suppressing the non-physical backpropagation of downstream errors to the upstream air state. This method takes the Mach cone spatial causal dual matrix as its core innovation, and the local control volume and differentiable interface flux are only used as auxiliary carriers to realize spatial causal constraints. It can reduce the risks of shock wave over-smoothing, position drift, local non-conservation and negative density pressure in air shock wave capture.

The application discloses a kind of stirling generator performance prediction method.This method is established by force balance equation and volume equation to the gas distribution piston, power piston, compression cavity and expansion cavity inside stirling generator respectively, combined with ideal gas equation, mass conservation equation and energy conservation equation, constructs the heat-dynamics coupling model of stirling generator including kinetic parameters and thermodynamic parameters;According to the input kinetic parameters, the running frequency, displacement amplitude of gas distribution piston and power piston and the phase difference of two pistons are calculated;Further solve the thermodynamic model, obtain the change of temperature, pressure, mass and mass flow of working medium;Then the results are substituted into motor model, obtain effective voltage, effective current and effective electric power;Through heat-dynamics coupling solution and combined with motor model, the whole process of heat-work-electricity conversion is solved and calculated, so as to realize the heat-dynamics-electricity parameter prediction of stirling generator, provide theoretical guidance for whole machine fault diagnosis and optimization design.

The application discloses a tunnel pressure fluctuation simulation method and device, equipment and a storage medium, and relates to the technical field of pressure simulation. The method comprises the following steps: obtaining a to-be-simulated pressure curve according to train outside pressure data of a train during train driving in a tunnel; determining flow rate time sequence data corresponding to the to-be-simulated pressure curve according to a pressure-flow rate relationship; the pressure-flow rate relationship is determined according to an ideal gas state equation and a mass-flow rate relationship; and controlling the gas flow rate of a numerical simulation model according to the flow rate time sequence data to simulate a tunnel pressure wave and obtain a simulated pressure curve. As can be seen from the above, the train driving in the tunnel is no longer simulated, but the pressure wave generated by the train extruding air in the tunnel is directly simulated; and the flow rate time sequence data is generated according to the pressure-flow rate relationship, so that the gas flow rate of the numerical simulation model is controlled according to the flow rate time sequence data to simulate the tunnel pressure wave, obtain the simulated pressure curve, and realize efficient pressure fluctuation reproduction.

The invention discloses an electrical control system for chemical production, relates to the field of electrical control, and realizes accurate management and control of the risk of migration of hydrogen to a chlorine side through multi-module cooperation. Integrating the zero current confirmation position, the pressure difference between the anode chamber and the cathode chamber and the hydrogen molar flow through a signal triggering module to generate a signal triggering position; when the washing purification module is triggered, a volume flow set value is calculated based on an ideal gas state equation, and a chlorine pipeline diverter valve is adjusted through a controller, so that the actual purification flow is matched with the set value to purify hydrogen-containing chlorine; when the gas release module is triggered, a chlorine side release valve is opened, the molar weight of gas needing to be released is calculated to serve as a target threshold value, after it is monitored that the actual release amount reaches the target threshold value, the valve is closed, and the pressure difference is updated; and the reset permission module generates a reset permission bit in combination with the update pressure difference and the consistency residual error, and starts reset to enable the system to return to a monitoring state when a condition is met. The system improves the safety and stability of chemical production.

The invention discloses a method for measuring the micro-leakage rate of target gas in an airtight container. The method comprises the steps that the target gas with the first pressure P1 is injected into the airtight container (10); placing the airtight container in an airtight cylinder (20); the airtight cylinder body is vacuumized, and high-purity gas with the second pressure P2 different from the target gas is injected; putting the airtight cylinder body into an isolation box (30), vacuumizing and standing for a plurality of days; the airtight cylinder body is taken out, and the concentration Cp of target gas in the airtight cylinder body is detected; and calculating the micro-leakage rate Q of the target gas in the airtight container based on the concentration Cp, wherein P2 is the pressure of the high-purity gas filled in the airtight cylinder body, Vg is the volume in the airtight cylinder body, Vc is the volume of the airtight container, Cp is the concentration of the target gas, t is the standing time, R is the ideal gas state parameter, and T is the absolute temperature of the airtight cylinder body.

The invention provides an intelligent pneumoperitoneum system with dynamic smoke removal and constant pressure functions and a using method, the intelligent pneumoperitoneum system comprises a suction and pneumoperitoneum all-in-one machine and a double-cavity aspirator head, the suction and pneumoperitoneum all-in-one machine comprises a shell and a containing space located in the shell, and a control module, a gas supply channel and a gas recovery and purification channel are arranged in the shell; the double-cavity aspirator head is connected with the gas supply passage and the gas recovery and purification passage; the system collects smoke concentration and pressure signals in the abdominal cavity in real time through the smoke concentration detection module and the outlet pressure gauge which are integrated in the double-cavity aspirator head and feeds back the smoke concentration and pressure signals to the control module. The control module constructs a closed-loop control algorithm based on an ideal gas state equation, the suction power of the suction module and the gas inlet rate of the pressure regulating module are dynamically and cooperatively regulated, and rapid removal of smoke in an operation and dynamic stability of pneumoperitoneum pressure are achieved. Two-stage waste gas filtration is integrated, it is ensured that exhausted gas is harmless, and the integrated guarantee of clear surgical view, coherent operation and patient safety is achieved.

The application discloses a kind of quality flow test methods of automobile safety air bag gas generator based on acceleration sensor, utilize rigid container, piston, acceleration sensor, refrigeration type infrared thermal imager, pressure sensor and data recording device;The linear motion process of piston is measured by acceleration sensor, and the volume of gas generated by gas generator is converted;Combining the measured gas pressure, temperature, the gas density is solved by ideal gas state equation;Gas volume and density are solved by gas mass flow and its dynamic change.By the application, the mass flow of mixed gas generated after ignition of air bag gas generator and the mass flow of single gas component can be measured, and a gas mass flow test method is provided for the research and production of actual air bag gas generator.

To provide a method for estimating a density of overheated steam, capable of easily grasping a density of overheated steam in a predetermined pressure state at a target predetermined temperature.SOLUTION: In a virtual density calculation step S11, a virtual density ρntp, which is a density of virtual overheated steam in a standard state, is calculated using an ideal gas equation of state, based on conditions of a temperature Tntp and a pressure Pntp in the standard state and a molecular weight of water M, assuming that the overheated steam is ideal gas and exists in the standard state. In a density estimation step S12, the virtual density ρntp calculated in the virtual density calculation step S11 is used to calculate a density ρest of overheated steam at a predetermined temperature Tpd and pressure Ppd based on Boyle's law, thereby estimating the density ρest of overheated steam at the predetermined temperature Tpd and pressure Ppd.SELECTED DRAWING: Figure 1

The invention discloses a high-precision high-temperature centrifugal pump performance index prediction method and device and electronic equipment, and the method comprises the steps: constructing a density coupling function of medium density, temperature and pressure according to an ideal gas state equation and a Tammann equation; embedding the density coupling function into a FLUENT solver through a user-defined function UDF, and performing real-time dynamic correction on the medium physical property of the calculation unit in an unsteady numerical simulation process to obtain a corrected physical property parameter; based on the corrected physical property parameters, FLUENT is adopted to conduct unsteady numerical simulation on the whole flow field of the high-temperature centrifugal pump to be predicted, and input shaft power, pressure and speed of an internal flow field and transient flow field data are obtained; and calculating lift and efficiency based on the input shaft power, pressure, speed and fluid inlet and outlet water heads. And accurate prediction of the pump performance indexes of the pump can be realized.

The invention discloses a product vacuum extraction method based on volume change, and relates to the technical field of vacuum extraction. The product vacuum extraction method based on the volume change comprises the following steps that the internal space of a product and the internal space of a vacuum extraction assembly form a closed space; calculating based on an ideal gas state equation PV = nRT, and designing a preset distance X that a piston needs to move; the piston is moved until the moving distance reaches X, so that the total volume of the extraction cavity and the interior of the product is increased, and the pressure in the product reaches the target vacuum pressure; and a sealed space is formed in the product. By moving the piston, the volume of the interior of the extraction cavity can be changed, namely the volume of the sealed space is changed, the number of original air molecules is not changed, the dispersed space is larger, the less mutual collision is, and therefore the pressure can be gradually reduced until the air pressure in the sealed space reaches the target vacuum pressure; according to the product vacuum extraction method, the precision that the internal pressure of the product reaches the target vacuum pressure is improved.

The present application belongs to the field of engine nozzle technology and relates to a design method, device, equipment, and medium for a hypervelocity non-ideal gas nozzle. The method comprises: obtaining design parameters, designing the inviscid profile and contraction section of the hypervelocity non-ideal gas nozzle, and obtaining the flow field of the hypervelocity non-ideal gas nozzle; using computational fluid dynamics methods, performing computational fluid dynamics simulation on the flow field and calculating the boundary layer thickness of the hypervelocity non-ideal gas nozzle; based on the boundary layer thickness, redesigning the inviscid profile and contraction section of the hypervelocity non-ideal gas nozzle, and correcting the boundary layer thickness to obtain an updated flow field; using computational fluid dynamics methods, performing computational fluid dynamics simulation on the updated flow field to obtain an updated flow field simulation result; and outputting the current hypervelocity non-ideal gas nozzle when it is determined that the updated flow field simulation result meets preset requirements. The present application can accurately design a hypervelocity non-ideal gas nozzle.

The invention belongs to the field of stratum elastic parameter analysis, and particularly relates to a shale pore compressibility coefficient measuring method. According to the determination method, alkane gas is used for replacing methane to serve as a saturated medium, the response of 1H in a magnetic field after shale cores are saturated with alkane is detected through nuclear magnetic resonance, and the pore space volumes of the shale under different confining pressures are quantitatively represented through a nuclear magnetic resonance T2 atlas and an ideal gas state equation. The saturation degree of the new saturated medium on the rock core is more sufficient, and the influence of shale micro-nano pores can be fully reflected; in the core saturation process, water swelling does not occur, and the influence of the pipeline blank volume does not need to be considered, so that the shale pore compressibility can be measured more accurately.