59 results about "Peak pressure" patented technology

The invention discloses a time-phased intelligent pressure regulation management method and system for secondary water supply, and belongs to the technical field of water supply management, and the method specifically comprises the steps: dividing a day into a water consumption peak period and a water consumption low period based on historical water consumption flow data, and determining the starting and ending time nodes of each time period; through hydraulic calculation and actual water supply pressure monitoring, a pressure control point at the tail end of the water supply system is locked, and water supply pressure data of the point are collected in real time; in the water consumption peak period, a peak pressurization control strategy is executed; in the water consumption low-peak period, analysis is conducted according to historical water supply pressure data of a tail end pressure control point, and a low-peak period pressure safety threshold value is set; a pressure instruction is sent to a control system according to the threshold value, and water supply equipment is controlled to output pressure according to the threshold value; the water supply pressure of a tail end pressure control point is monitored in real time, and when the pressure is lower than a low-peak-period pressure safety threshold value, pre-alarm is triggered, and pressure changes are continuously recorded; and if the pre-alarm state is not finished continuously, switching to a peak-period peak pressurization control strategy.

The invention discloses an intelligent hydraulic system of a roller press and a control method. The method comprises the steps that roll gap and pressure signals are collected in real time, and the average roll gap, the roll gap difference and the change rate are calculated; calculating an optimal system total pressure setting reference value in real time through a preset pressure-roll gap-material characteristic coupling model based on the target peak pressure, the current average roll gap and the material characteristic parameters; judging the working condition according to the roll gap difference and the change rate: under the stable working condition, taking the reference value as a double-side pressure set value; under the abnormal working condition, differential adjustment is carried out on double-side pressure set values on the basis of the abnormal working condition; and finally, the pressure set value is output to the hydraulic executing mechanism, and the state of the energy accumulator set is synchronously adjusted. The system correspondingly comprises a signal sensing unit, a hydraulic execution unit, an adjustable rigidity energy storage unit and an intelligent control unit. Constant-effect, stable and self-adaptive operation of the roller press under variable working conditions is achieved, and the grinding efficiency, the equipment stability and the intelligent level are remarkably improved.

The application discloses a kind of multi-stage linkage explosion venting test methods combined with powdery combustion inhibitor, it is related to explosion-proof engineering and safety detection technical field;The method is by constructing with explosion venting device, ignition system, powdery inhibitor delivery system and pressure and optical sensor test cabin, uses PLC to realize ignition, pre-delivery, pressure relief trigger, synchronous inhibition and afterflame inhibition and so on multi-stage linkage control;And through pressure, temperature and flame sensor real-time acquisition of multi-dimensional data of explosion process;By before ignition, ignition instant and in the process of pressure relief with different doses of powdery inhibitor, the explosion suppression performance under different linkage strategies can be systematically evaluated;The application can simultaneously obtain peak pressure, pressure rise rate, flame propagation speed and re-burning conditions and other multi-parameters, realize the quantitative evaluation of the explosion suppression efficiency of powdery combustion inhibitor under multi-stage linkage explosion venting conditions, with the advantages of good data integrity, strong repeatability and suitable for standardization explosion-proof test method construction.

The utility model belongs to the technical field of hydraulic oil cylinders, and particularly relates to an anti-explosion hydraulic oil cylinder which comprises a cylinder body. A cylinder seat and a piston are arranged in the cylinder body; an oil inlet / outlet is formed in the cylinder body; a main oil way and an auxiliary oil way are arranged in the cylinder base. A buffer seat is further arranged on the outer side of the oil inlet / outlet; the buffer seat is connected with the auxiliary oil way through a branch; and an opening and closing mechanism is arranged in the branch. According to the design, peak pressure and temperature generated by hydraulic oil in the cylinder body can be effectively relieved. In other words, when the piston works aiming at an object with the limit weight and moves to the maximum stroke, the hydraulic oil is in the state with the highest oil pressure and the highest oil temperature, the high oil pressure can push the opening and closing mechanism to be opened during oil outlet, and part of the hydraulic oil enters the buffer seat through the branch; the other part of hydraulic oil normally returns to the oil inlet / outlet through the main oil path; and hydraulic oil entering the buffer seat cannot immediately return to the oil inlet / outlet, so that the oil outlet pressure and temperature are greatly relieved.

The invention provides an air bag pressure linkage adjusting method and system based on airway peak pressure feedback, relates to the technical field of medical equipment control, and aims to solve the problems of control algorithm lag, lack of linkage mechanism, poor clinical practicability, insufficient safety redundancy and the like in the prior art. According to the method, on the basis of airway peak pressure values of a plurality of continuous breathing cycles, an air bag pressure target value is increased in a stepped mode one by one in the breathing cycles, and stable state judgment is synchronously conducted till the airway peak pressure is stable; in the stable maintaining stage, the airway peak pressure is continuously monitored, and if the rise exceeds a preset fluctuation threshold value, the current locking target value is taken as the reference to be increased step by step again according to the preset step length; and if the reduction exceeds the preset fluctuation threshold value, the target value is reset as the initial airway peak pressure, and step adjustment is performed again until the airway peak pressure is stabilized again. The problems existing in the prior art are solved, and dynamic cooperative adjustment of the airway peak pressure and the airbag pressure is achieved.

The application discloses a kind of detection methods based on engine cold test machine's cylinder bore scratch, it is related to engine detection field, comprising: acquisition measured engine under constant speed condition Torque data, extract the maximum, minimum and average of the torque of each cylinder;When torque data is out of limit, determine target cylinder, and calculate the difference between its maximum and minimum, obtain single cylinder torque span value;If the span value exceeds the determination limit, then trigger exhaust back pressure test link, acquisition target cylinder single cylinder exhaust peak pressure;If the peak pressure is lower than the peak pressure of normal cylinder, and difference reaches abnormal drop threshold, then determine that there is cylinder bore scratch.The present application effectively amplifies weak fault signal by combining torque span feature and exhaust back pressure feature, without disassembly, cylinder bore scratch and pure mechanical bearing defect can be accurately distinguished, and the sensitivity and accuracy of online detection of mass production line are improved.

The application provides a roll gap control method of a double-roller thin strip process and a double-roller thin strip casting device. In the preparation process, relative movement between two rollers is controlled, or relative movement between the two rollers and control of the roll system in the form of overall movement are controlled to move on the double-roller thin strip casting machine, so that the roll gap only produces floating which can play a role in stabilizing the process and / or improving the quality of the blank. Compared with the traditional roll gap two-way floating method, the technical solution of the application does not cause two-way fluctuation of the roll body clamping force, and does not produce fluctuation of the thickness of the blank. The shear thinning behavior of the semi-solid material can be inhibited, so that the peak pressure of the molten pool is weakened, which is beneficial to real-time control, can prevent various process stability problems such as liquid leakage of the side sealing plate, damage of the side sealing plate, strip jamming and strip breaking, and can also prevent various blank quality problems such as cracks and wrinkles.

The invention discloses a water conservancy pipeline device for a water conservancy project, relates to the technical field of water conservancy projects, and aims at solving the technical problems that when an air bag expands every time, stress distribution is not uniform, aging of the bag body can be accelerated, and the service life is greatly shortened. The performance of the rubber liner air bag type water hammer eliminator is improved through the multi-dimensional design; the rubber liner air bag body adopts a center thickened gradient structure and is matched with the flow guide design of the air guide cover to guide water hammer shock waves to a central area, so that edge stress concentration is reduced; extension feelers at two ends of the air bag and guide sheet pressure heads form dynamic press fit to strengthen stress dispersion at two ends; the thermoelectric driving expansion head opens the air bag in advance, and the fluid impact angle is optimized; the stable expansion ring balances the edge expansion stress through the current effect; the air guide cover forms annular flow guide, energy dissipation time is prolonged, and water hammer peak pressure is reduced. The design effectively solves the problem of uneven stress distribution of the air bag, improves the water hammer protection efficiency, prolongs the service life of the air bag, and guarantees the safe operation of the water conservancy pipeline.

An interface bonding failure test method, system, storage medium and program product, relate to the field of testing or analyzing materials by means of determining chemical or physical properties of materials, in the method, the interface bonding state between the pole piece coating and the current collector is evaluated by performing a single loading and unloading cycle. In the loading stage, a first resistance value is measured when the pressure reaches a preset target detection pressure, and then the pressure is continuously increased to a preset peak pressure (the pressure is greater than the target detection pressure but less than the yield strength of the current collector). In the unloading stage, a second resistance value is measured when the pressure decreases back to the preset target detection pressure. By comparing the difference between the two resistance values with a preset hysteresis threshold, the interface bonding state is determined: if the difference is greater than the threshold, it is determined that there is interface bonding failure. The present application is used to reduce the difficulty of identifying overpressure risk and defining the best roll pressure process window.

The invention provides a calibration method of an internal pressure-resistant tester, belongs to the field of calibration of internal pressure-resistant testers, and can solve the problem that a pressure index and a time index cannot be accurately detected when the internal pressure-resistant tester is calibrated. The calibration method comprises the following steps: connecting the high-frequency digital pressure gauge with the internal pressure resistance tester through the interface connecting device; the memory of the high-frequency digital pressure gauge is reset, and the detection recording function is restarted; starting the internal pressure resistance tester to carry out pressure detection, and continuously detecting for three times under the same detection condition; pressurizing is stopped, the recording function of the high-frequency digital pressure gauge is stopped, and data recorded by the high-frequency digital pressure gauge is exported; and analyzing the exported data, and judging whether the pressure index and the time index meet requirements or not. The method can be applied to calibration of the glass bottle / PET bottle internal pressure resistance tester, key indexes such as peak pressure, pressure increasing rate, dwell pressure and dwell time which are difficult to measure by a conventional method of the glass bottle / PET bottle internal pressure resistance tester are accurately verified, the index detection effect of the glass bottle / PET bottle internal pressure resistance tester is ensured, and safety risks such as bottle explosion are effectively prevented.

The invention relates to the technical field of hydraulic control, in particular to a control method of hydraulic pumps, a hydraulic control system and an operation machine, the control method is applied to the hydraulic control system, the hydraulic control system comprises a plurality of hydraulic pumps, a hydraulic accessory and a main valve, and the main valve is used for converging hydraulic oil output by the hydraulic pumps and enabling the hydraulic oil to flow into the hydraulic accessory. The control method comprises the steps that the required pressure of the hydraulic accessory and the initial peak pressure of an oil inlet way input into the hydraulic accessory are obtained; and under the condition that the difference value between the initial peak pressure and the required pressure is not within the first preset pressure range, the output flow ratio of the multiple hydraulic pumps is adjusted according to a preset adjustment strategy till the difference value between the peak pressure after flow adjustment and the required pressure is within the first preset pressure range, the target flow corresponding to each hydraulic pump is recorded; and each hydraulic pump is controlled to work at the corresponding target flow. By adopting the control method of the hydraulic pump, the pressure loss of the hydraulic control system can be reduced, and the energy consumption of the system is reduced.

The invention relates to the technical field of closestool control, in particular to an intelligent closestool with an intelligent displacement adjusting function and a control system, which are used for extracting key features based on dynamic waveform data and calculating a pipeline pneumatic rigidity coefficient representing the current physical state of a pipeline in combination with a known test fluid volume. Then, the coefficient and the waveform characteristics are intelligently compared with a preset pollution discharge working condition matrix covering multiple typical fault modes, and different internal causes such as rigid blockage, air resistance and overhigh negative pressure can be accurately distinguished. Finally, a driving signal is generated to precisely regulate and control the pulse rhythm, the peak pressure and the duration time of the flushing water flow. The process realizes treatment according to indications, not only can effectively solve various hidden faults with minimum water consumption and energy consumption, but also can preventively maintain the water seal and avoid return overflow, and realizes remarkable resource saving and system protection while improving the reliability.

A press arrangement for pressing a web of fibrous material includes at least two presses which are arranged one behind the other in a direction of travel of the web of fibrous material, the at least two presses including a first press and a second press following the first press, the first press including a first press nip, the second press including a second press nip which is an extended press nip, the second press being configured for being operated at a linear load of at least 500 kN / m, the second press being configured such that a quotient of an average pressure and a peak pressure in the second press nip is less than 0.5, the second press being configured for applying the peak pressure of at least 12 MPa onto the web of fibrous material.

The application relates to an intelligent brace adaptive pressure control method and device based on a subcutaneous pressure prediction model, wherein the method comprises the following steps: collecting surface pressure distribution data between a brace and a preset key area of skin in real time; extracting a pressure peak value, a pressure gradient, a pressure duration and a pressure change rate, and fusing the collected physiological parameters of a user to construct a multi-modal feature vector; inputting the multi-modal feature vector into a pre-trained subcutaneous pressure prediction model to predict a subcutaneous pressure experience value of the user; and adjusting the inflation amount of an air bag inside the body of the intelligent brace if the subcutaneous pressure experience value exceeds a preset safety pressure threshold. The application can predict the subcutaneous pressure experience value by collecting surface pressure data in real time and combining physiological parameters, can give an early warning before actual subcutaneous tissue damage occurs, and can cope with pressure changes caused by user activities and posture changes by dynamically adjusting the inflation amount of the air bag.

The invention relates to the technical field of mine filling, and discloses a high-flux slurry continuous pumping system for underground goaf governance, which comprises a pumping driving unit, a pipe network sensing unit and a central control unit, and is characterized in that sine disturbance signals are superposed at a pumping reference frequency through the central control unit, and pressure disturbance waves carrying phase characteristics are constructed; extracting a phase deviation parameter of the pipe network response waveform, and identifying that the pipeline is in a metastable state deposition stage when the change rate of the phase deviation parameter exceeds a threshold value; outputting a flutter signal to induce interface softening of the sediment, and connecting and outputting an asymmetric pressure pulse of which the rising edge slope is greater than the falling edge slope so as to peel the sediment; according to the method, the abnormal flow resistance is recognized in the deposition stage before dominant fluctuation of the outlet pressure occurs, the instantaneous peak pressure intensity in the blockage clearing process is reduced through a softening and stripping mechanism, and the structural safety of a pipe network under the high-throughput conveying working condition is maintained.

The utility model provides a diaphragm fixing device for generating explosive waves. The diaphragm fixing device is composed of a movable section, a high-pressure diaphragm, a middle section, a low-pressure diaphragm, a fixed section, a hydraulic cylinder and a guide rod. Cylinder bodies of the four hydraulic cylinders installed in parallel are fixedly connected with the fixed section, and cylinder rods are fixedly connected with the movable section. The high-pressure diaphragm is clamped and fixed with the middle section through the movable section, and the low-pressure diaphragm is clamped and fixed with the fixed section through the middle section; three guide rods mounted in parallel are fixedly connected with the fixed section and penetrate through the middle section and the movable section; the diaphragms are fixed in a movable mode, the difficulty in the diaphragm mounting and dismounting process is reduced, the diaphragm mounting and dismounting efficiency is improved, a double-diaphragm structure is adopted, the pressure difference between the two sides of the diaphragms is reduced by dividing the pressure bearing cavity, the peak pressure and the positive pressure time in the explosion wave test process are prolonged, and the explosion wave test efficiency is improved. And the application range of the explosion wave test is expanded.

The invention provides a real-time optimization method for the size of an oil nozzle in the flowback stage after shale gas horizontal well fracturing. The method comprises the following steps that firstly, production dynamic data in the flowback stage of a shale gas well is recorded; 2, obtaining continuous and complete pressure decreasing data based on the pressure data before the peak pressure is reversely deduced; thirdly, according to the shale gas well flow-back stage production dynamic data and the continuous and complete pressure decline curve, flow-back stage dynamic characteristic parameters are calculated; and 4, optimizing the size of the oil nozzle in the flow-back stage in real time based on the dynamic characteristic parameters in the flow-back stage. Dynamic changes of various key indexes under different oil nozzle systems are calculated in real time by combining production dynamic data recorded at the shale gas well flowback stage site according to time intervals, the real-time optimization method for the size of the oil nozzle in the shale gas horizontal well after-fracturing flowback stage is established for the first time, real-time optimization of the oil nozzle in the shale gas well flowback stage is achieved, and real-time optimization of the oil nozzle in the shale gas well flowback stage is achieved. The shale gas development effect is improved.

Method for a power machine (10) comprising the following: in response to the fact that a predicted peak cylinder pressure for a planned main fuel injection into a cylinder (30) occurs later than at a threshold time, dividing the planned main fuel injection into at least a first and a second injection, wherein the first injection is advanced relative to the time of the planned main fuel injection; and setting a time and duration for both the first and second injections based on a peak pressure target of the cylinder (30), wherein the power engine (10) is a turbocharged power engine comprising an inlet compressor driven by an exhaust gas turbine, and wherein the duration of the second injection is further set based on an inlet temperature of the turbine and wherein the duration is shortened if the turbine inlet temperature increases above a threshold temperature.

The invention discloses a leakage rate measuring device and method for a rotor engine end face sealing device. The leakage rate measuring device comprises a pressure stabilizing air source unit, a rotating mechanical unit, an air tightness testing unit and an oil way unit. The air tightness testing unit is used for providing a pressure stabilizing air source with consistent peak pressure in the working process of the rotor machine under the actual working condition; the oil way unit is used for spraying lubricating oil into the rotor cavity; the rotary mechanical unit simulates the relative movement of the rotor engine end face and the end face sealing piece; the measurement of a rotor cavity in the air tightness test unit is equivalent to rotor end face leakage, and the force of the rotor cavity acting on a rotating flat plate can be adjusted by adjusting a one-way manual lifting platform. The acting force is equivalent to the elastic force of a spring of the end face sealing device, and the gas leakage amount is obtained by measuring the pressure drop of the surge tank or through a gas flow meter during the gas tightness test. In the sealing performance test of the sealing oil film, the oil injection quantity to the rotor cavity is continuously changed, and an incidence relation curve between the lubricating oil injection quantity and the sealing leakage quantity of the oil film can be dynamically established.

Device comprising: a filter circuit (144) configured to filter vibration data within a predetermined combustion period of the machine, wherein the vibration data represent a vibration of an internal combustion engine (110), the vibration data comprising voltage signals; a PCP determination circuit (146) which is functionally and communicatively connected to the filter circuit (144) and is configured to determine a cylinder peak pressure (PCP) of a combustion cycle of the internal combustion engine (110) on the basis of the filtered vibration data, wherein the PCP corresponds to a maximum of absolute values ​​of the voltage signals or a difference between the maximum and a minimum of the absolute values ​​of the voltage signals; an LPP determination circuit (148) which is functionally and communicatively connected to the filter circuit (144) and configured to determine a location of the cylinder peak pressure (LPP) of the combustion cycle of the internal combustion engine (110) based on the filtered vibration data, wherein the PCP and the LPP represent a functional property of the combustion cycle; and an ignition timing circuit which is functionally and communicatively connected to the PCP determination circuit and the LPP determination circuit, wherein the ignition timing circuit is configured to modify an ignition timing of the internal combustion engine on the basis of the determined PCP and the determined LPP.

The utility model belongs to the technical field of shoe soles, and particularly relates to an air cushion shoe sole with a flowing air chamber, which comprises a midsole and an outsole, a plurality of matching holes are arranged at the bottom of the midsole, a plurality of U-shaped grooves are arranged among the matching holes, and anti-skidding bumps and air cushion bumps are arranged at the bottom of the outsole. The insole and the outsole are matched to form an air chamber, the matching holes are hemispherical, and the air cushion protruding blocks are higher than the anti-skid protruding blocks. Automatic adjustment of air pressure between the air chambers is achieved through the communicating grooves, overlarge local pressure intensity is avoided, foot impact peak pressure is reduced, and joint loads are relieved.

A control method for an injection molding machine for forming an injection molded article by injecting a molten resin in a cylinder into a mold, in which an injection molded article evaluated as a qualified product in advance is used as a reference product, and in a primary injection molding process of the reference product, the injection molded article is subjected to injection molding in the mold. A peak pressure in a mold, and a pressure reduction time from an injection start time to a time at which the pressure in the mold drops to zero, or a pressure integral value from the injection start time to a time at which the pressure in the mold drops to zero, are acquired. And adjusting the temperature of the charging barrel so that the peak pressure in the mold becomes the peak pressure in the mold of the reference product, and adjusting the temperature in the mold so that the pressure reduction time or the pressure integral value becomes the pressure reduction time or the pressure integral value of the reference product.

The invention relates to the technical field of medical instruments, in particular to a medicine coating capsule which comprises a pressurizing cylinder, a driving rod used for driving the pressurizing cylinder to stretch out and draw back, a pressure gauge installed on the pressurizing cylinder, a connecting mechanism arranged on one side of the pressurizing cylinder, a pressure hose used for connecting the pressurizing cylinder with the connecting mechanism, and a sheathing canal installed on one side of the connecting mechanism. A flow limiting component is arranged in the connecting mechanism and comprises a flow limiting roller and buffering components symmetrically arranged at the two ends of the flow limiting roller, and through the synergistic effect of the flow limiting roller and the buffering components, the instantaneous impact force of normal saline is converted into rotation kinetic energy of the flow limiting roller, so that the flow limiting roller rotates, and the flow limiting roller rotates. The elastic component is used for absorbing energy, and when the pressure exceeds a safety threshold value, the elastic component counteracts on the flow limiting roller to limit rotation of the flow limiting roller, so that peak pressure is automatically reduced, vascular rupture or bleeding caused by abrupt pressure change when the medicine balloon expands or contracts is avoided, and the operation safety is remarkably improved.

The invention relates to the technical field of cushion collar design, and particularly provides a design method of a labyrinth cushion collar, a cushion structure, a hydraulic oil cylinder and a hoist, the design method comprises the following steps: firstly, determining the length, the inner diameter and the outer diameter of the cushion collar according to the size and energy conservation of the hydraulic oil cylinder; secondly, deriving a throttling area curve of the outer surface of the cushion collar according to a force balance equation and a flow equation of a hydraulic oil cylinder piston so as to determine the tapping position of a damping hole in the cushion collar; then the number and the hole diameter of damping holes are determined according to the expected buffer pressure curve and acceleration curve; according to an energy dissipation mechanism and the mathematical model of the cushion collar, the flow resistance series and the flow channel structure of the cushion collar are determined; according to the model, the buffer speed curve and the buffer pressure curve of the buffer sleeve are quickly obtained from the peak pressure and the maximum initial speed, and according to test verification, the method can quickly and accurately design the buffer device meeting the requirement of high-speed heavy-load operation of the quick hydraulic hoist, and the problem that the complex flow channel buffer device is difficult to design and verify is solved.

The invention discloses a multi-mode shock wave controllable loading system and a working method thereof. The multi-mode shock wave controllable loading system comprises high-pressure sub-air chambers and a transmitting tube, wherein the high-pressure sub-air chambers are annularly distributed around a high-pressure main air chamber, the volumes of the high-pressure sub-air chambers are in gradient distribution, the transmitting tube is arranged on one side of the high-pressure air chamber, and a transmitting film is arranged between the transmitting tube and the high-pressure main air chamber; the high-pressure sub-gas chambers are connected with the high-pressure main gas chamber through electromagnetic valves and are used for sequentially or synchronously triggering the selected electromagnetic valves according to a set time sequence when high-pressure gas in the high-pressure main gas chamber reaches a set pressure threshold value, so that the gas with set pressure in the high-pressure sub-gas chambers is released to the transmitting tube; and multi-peak shock wave waveforms or superposed single-peak shock wave waveforms with different peak pressures are formed. Annular array type high-pressure sub-air chambers in volume gradient distribution are designed, and by means of the pressure of the high-pressure sub-air chambers and the cooperative time sequence of a multi-channel high-speed electromagnetic valve, multi-peak shock wave waveforms or superposed single-peak shock wave waveforms with different peak pressures are generated, and high-precision continuous adjustment of shock wave waveform parameters is achieved.

The invention discloses a full-automatic pressurized water recording system based on the Internet of Things, belongs to the technical field of the Internet of Things, and aims to solve the problem of pressure fluctuation caused by response lag and operation errors of a manual adjustment mode in traditional pressurized water operation. Comprising a construction parameter input module used for receiving construction parameters input by a user; the data acquisition module is used for acquiring real-time injection rate data and pipeline pressure data; the data processing module is used for calculating accumulated flow based on the real-time injection rate data and calculating gauge pressure and peak pressure based on the pipeline pressure data; the report generation and display module is used for generating a pressurized water record report according to the accumulated flow, the gauge pressure and the peak pressure and displaying a pressure and flow curve in real time; the self-adaptive PID control module is used for dynamically adjusting the rotating speed of the plunger pump so as to maintain the pipeline pressure within a target pressure range; and the safety protection module is used for outputting a shutdown instruction to stop operation of the plunger pump when it is detected that the pipeline pressure exceeds the safety pressure limit value.

The application relates to the technical field of gears, and provides a crescent plate-gear gap variable internal meshing gear pump capable of reducing flow pulsation, which comprises a pump body, an external gear, an internal gear and a crescent plate, the external gear and the internal gear are arranged in the pump body, the external gear and the internal gear are offset meshed, the crescent plate is arranged between the tooth top of the external gear and a tooth top circular arc surface of the internal gear, and the crescent plate is gap-fitted with the external gear and the internal gear respectively. The variable gap in the pump operation process is realized through the crescent plate radius design, the flow unevenness caused by flow pulsation, the pump internal peak pressure caused by flow backflow and the cavitation damage caused by cavitation effect are reduced under the condition that the flow change of the pump is small.

The invention discloses a shock wave simulation method for a shield segment explosion-proof test. Precise control over peak pressure fluctuation and pulse width errors is achieved by combining a high-precision mass flowmeter and electromagnetic parameter regulation and control on the basis of a quantitative relation model constructed based on the fluid dynamics theory, meanwhile, an electromagnetic pre-compression and chemical detonation composite driving mode is adopted, shock waves with the rise time shortened and the peak pressure reaching 300 MPa or above are generated, and the shock waves can be applied to the field of hydraulic engineering. The steep front edge and high-frequency oscillation of real explosion are reproduced, the waveform limitation of single air pressure driving is broken through, a multi-field coupling monitoring system achieves full-time-history data capture of duct piece strain, displacement, temperature and the like through a high-frequency sensor and a high-speed camera system, weak parts are accurately recognized, meanwhile, the 1500-DEG C high-temperature simulation capacity is achieved, and the system is suitable for being used in the field of high-temperature simulation. The critical failure pressure is accurately determined in combination with a stepped pressure test, various extreme working condition requirements are met, nanosecond synchronization and safety redundancy design is achieved through an intelligent control system, the experiment efficiency is improved, and a high-fidelity and repeatable test platform is provided for research on the anti-knock performance of the shield segment.

The invention relates to an intelligent brace self-adaptive pressure control method and device based on a subcutaneous pressure prediction model. The method comprises the steps that surface pressure distribution data between a brace and a skin preset key area are collected in real time; extracting a pressure peak value, a pressure gradient, a pressure duration time and a pressure change rate, and fusing the pressure peak value, the pressure gradient, the pressure duration time and the pressure change rate with the collected physiological parameters of the user to construct a multi-modal feature vector; inputting the multi-modal feature vector into a pre-trained subcutaneous pressure prediction model, and predicting a subcutaneous pressure experience value of the user; if the subcutaneous pressure experience value exceeds the preset safety pressure threshold value, the inflation volume of an air bag in the intelligent brace body is adjusted. According to the method, the subcutaneous pressure experience value is predicted by collecting the surface pressure data in real time and combining the physiological parameters, early warning can be conducted before actual subcutaneous tissue damage occurs, and pressure changes caused by user activities and posture changes are dealt with by dynamically adjusting the inflation volume of the air bag.

The invention discloses a near-field detonation pressure testing device based on liquefied air phase change rock breaking and a using method, and the near-field detonation pressure testing device based on liquefied air phase change rock breaking comprises a testing cylinder, a liquefied air energy storage module, a pressure measuring module and a triggering module. The using method is based on the liquefied air phase change rock breaking near-field detonation pressure testing device. According to the method, an underwater explosion pressure wave exponential attenuation characteristic is utilized, explosion peak pressure of different near-field distances is measured, a pressure wave attenuation formula is solved, a theoretical value of explosion center peak detonation pressure is obtained through calculation, and the near-field detonation pressure testing capability and precision are remarkably improved; the problem that the test result is difficult to convert into the detonation center detonation pressure due to the gas compression and complex phase change process in the traditional liquefied air energy storage tube detonation pressure test is effectively solved.