65 results about "Rate equation" patented technology

The invention relates to a method for analyzing the residual life of a storage tank through ANSYS software. The method mainly comprises the following steps that (1) a computer supporting ANSYS is used, collected storage tank data are input to the computer in the form of a database or a text, a finite element model of the corroded storage tank is established through the ANSYS software, and corresponding boundary conditions and an external load are applied to the finite element model according to the actual stress condition of the storage tank; (2) regression processing is conducted on experimental data points through a fatigue crack propagation law Paris formula, and a corrosion fatigue rate equation under the corresponding conditions is obtained; (3) the critical invalid wall thickness when the storage tank loses efficacy is determined according to a predicted value of the corrosion rate; (4) according to the critical invalid wall thickness when the storage tank loses efficacy due to corrosion, a storage tank residual life prediction model is established, and the approximate analysis method is used for calculating the residual life of the storage tank under the condition of uniform corrosion.

The invention discloses an estimation method of the service life of a Hall thruster, which relates to a method for estimating the service life of the Hall thruster. The invention solves the problem that the current full service life test to the Hall thruster has long time consumption and great cost consumption. Ionic bombardment is carried out to an easy sputtering ceramic tube, and within the time t, the bombardment thickness of the surface of the ceramic tube is h, wherein, the angle sputtering coefficient of the easy sputtering ceramic tube Y' (Theta) is equal to n1 multiplied by Y' (Theta), the energy sputtering coefficient S(E) is equal to n2 multiplied by S(E), and the tube surface density N is equal to n3 multiplied by N, wherein, Y' (Theta), S(E) and N are respectively the angle sputtering coefficient, the energy sputtering coefficient and the tube surface density of the ceramic tube of the Hall thruster passage; the service life of the Hall thruster with the passage thickness of h can be deduced according to the radial corrosion rate equation and the equation of the corroded thickness of the wall surface of the Hall thruster, that is, t is equal to (n1 multiplied by n2 divided by n3) multiplied by t. The method can carry out effective estimation and evaluation of the full service life of the Hall thruster within a short time, thus greatly reducing experimental time, lowering cost, and having the advantage of being direct and reliable, and the reliability of the method is higher than the service life prediction carried out to the thruster by adopting numerical calculation.

The invention provides a liquid static pressure guide rail oil film thickness control system and method based on oil temperature compensation. According to the method, a flow rate equation between guide rails is built; the flow rate equation is subjected to linearization; a guide rail stress equation is built; then, the linearized flow rate equation and the guide rail stress equation are subjected to Laplace transformation, so that an oil film thickness response load mechanism is obtained. For the oil film thickness control, the set oil film thickness is compared with the actual oil film thickness detected by a sensor, a difference value signal is subjected to control algorithm calculation, then, through signal conversion and power amplification, a simulation signal is obtained; the simulation signal is used for controlling an alternating servo motor and a proportional overflow valve, and the alternating current servo motor drives a variable pump, so that the oil flow rate of oil liquid outputted by the variable pump adapts to the flow rate required between movable and fixed guide rails, meanwhile, when the oil temperature changes, the pressure of the proportional overflow valve is controlled by a computer, and the change of the static pressure guide rail oil liquid pressure due to temperature change is compensated.

An electronically controlled hydraulic brake system is configured to obtain an attainment brake hydraulic pressure which can be achieved when a motor drive current command value is applied to a pressure increasing pump motor, to set a virtual initial pressure of the brake hydraulic pressure, to obtain a linear compensation executed attainment brake hydraulic pressure by linearly compensating the attainment brake hydraulic pressure using the actual brake hydraulic pressure, to calculate an ideal flow rate of the pressure increasing pump from a hydrodynamic flow rate equation, to obtain the linear compensation executed attainment brake hydraulic pressure by executing an inverse calculation of the flow rate equation from the ideal flow rate and the actual brake hydraulic pressure, and to obtain a linear compensation executed motor drive current command value by executing an inverse calculation of the calculation for obtaining the linear compensation executed attainment brake hydraulic pressure.

The invention provides a method for synchronously optimizing the ammonia injection quantity and the ammonia covering rate of a diesel engine Urea-SCR system. The method comprises the following steps that 1, a system tri-state nonlinear model is set up; 1-1, a system tri-state model is set up based on a main chemical reaction and rate equation; 1-2, NOx and NH3 concentration changes are taken as the quasi-stable state, only ammonia covering rate dynamic performance is taken as the unique state, and a one-state reduced-order model is set up; 2, a genetic algorithm is adopted in Matlab so that the error of the predicted values of NOx and NH3 concentrations in tail gas of an outlet of a catalyzer and actual measurement data can be minimum, and model parameters are obtained through recognition;3, the recognized model parameters are used for the optimization process of an NSGA-II algorithm, the best optimal solution is selected according to the limit value requirement, and the optimized urea feed rate and ammonia covering rate, the maximum NOx conversion efficiency and the ammonia storage quantity are obtained; and 4, simulation is carried out, and an engine full work condition optimization MAP is set up.

A method of determining the yaw rate ({circumflex over (ω)}_t) of a target vehicle in a horizontal plane by a host vehicle equipped with a radar system, said radar system including a radar sensor unit adapted to receive signals emitted from said host vehicle by said target, comprising: emitting a radar signal at a single time-point instance and determining from a plurality (m) of point radar detections measurements captured from said target vehicle by said radar sensor unit in said single radar measurement instance, the values for each point detection of range, azimuth and range rate; [r_i, θ_i, {dot over (r)}_i]; determining the values of the longitudinal and lateral components of the range rate equation of the target (c_t, s_t) from the results ({dot over (r)}_i, θ_i,) and the sensor unit or host vehicle longitudinal velocity and v_s is the sensor unit or host vehicle lateral velocity; determining the orientation angle of the target (γ_t,scs); determining the target center (x_t and y_t) from the results (r_i, θ_i); determining a line l_PH perpendicular to the orientation of the target and passing through the center of the target (x_t,c,scs, y_t,c,scs); determining a line l_CA passing through the center of rotation of said target and the position of radar sensor unit of said vehicle; determining the intersection point of the lines l_CA and l_PH being the position of the center of rotation [{circumflex over (x)}_t,COR, ŷ_t,COR] of the target; h) estimating and yaw rate {circumflex over (ω)}_t from the position of the center of rotation found in step f) and components of range rate equation of the target (c_t or s_t) of step b).

The invention discloses an optical fiber raster sensor patch shaped like a Chinese character 'wang'. The whole patch is of a left-right symmetrical structure shaped like the Chinese character 'wang', and the patch is of an integrally formed structure. The patch comprises a stress temperature transverse edge, a single temperature transverse edge, a pasting edge and two connection portions. The stress temperature transverse edge is connected with the single temperature transverse edge through one of the connection portions, and the single temperature transverse edge is connected with the pasting edge trough the other connection portion. According to the patch, an optical fiber raster of a second strip-shaped hole can directly measure the temperature of the structure, the stress of the structure can be obtained by subtracting the result of the optical fiber raster of the second strip-shaped hole from the result of the optical fiber raster of a first strip-shaped hole, chirping of the optical fiber raster can be prevented, the size of all parts of the patch can be designed according to the measurement requirements of different occasions in combination with an average strain transfer rate equation, and the patch is made to be compact in size and suitable for pasting.

The invention relates to an equivalent circuit model establishing method of a Ge/Si SACM structure avalanche photodiode and belongs to the technical field of semiconductor photodiodes. The method is based on Ge/Si heterojunction features. A Ge/Si SACM-APD device is subjected to theoretical analysis from the physical mechanism in the device. An APD equivalent circuit model is established from four parts of an APD rate equation, noise current, dark current and stray parameters. The method comprises the steps that 1. a physical model is divided into a plurality of parts, and a carrier transportation equation is established according to each structure layer; 2. a sub circuit module corresponding to each part is established; and 3. the sub circuit modules are connected with each other, and the equivalent circuit model is established. According to the method, the silicon-based APD device can be simulated and designed conveniently, and good application prospect is achieved.

The invention provides a method for evaluating the degree of parallel SVG (H-bridge cascade) higher harmonic circulating current, belongs to the technical field of power quality analysis and control, and aims to provide a circulating current access and static equivalent model according to the harmonic circulating current problem generated after parallel connection of SVG with a cascade H-bridge cascade structure and provide a method for evaluating the degree of parallel SVG (H-bridge cascade) higher harmonic circulating current based on indirect detection technology. The method comprises the following steps: constructing a model; analyzing the circulating current rate of two 2-cascade parallel SVG; simplifying calculation; calculating an actual circulating current rate equation; fitting each set of correction factor discrete values by utilizing a least square method in frequency bands; further pushing out a circulating current general formula; and calculating the criterion condition of the actual circulating current degree. The method can be used for indirectly and quantitatively analyzing the parallel SVG circulating current phenomenon by a simple linear mode, thereby laying a technical foundation for future detection analysis and inhibition work of higher harmonic circulating current among SVG.

The invention discloses a bistatic measurement method for mobile radiation source centre frequency. The method comprises the following steps of: supposing a measured target to move uniformly; synchronously measuring the frequency of a mobile target radiation signal in real time by using two monitoring station receivers; respectively obtaining a ratio of tangential velocities between adjacent nodes according to Doppler frequency excursion change rate equations; approximately expressing the ratio of the tangential velocities between the adjacent nodes by the ratio of frequency differences between the adjacent nodes according to the definition of Doppler change rate; after substituting the ratio relationship of the tangential velocities into a velocity identical relational expression between the adjacent nodes, respectively obtaining a function equation about wavelength-velocity by using the two measuring stations; and simultaneously solving for eliminating unknown target velocity to obtain an analytical formula of the target signal centre wavelength. The method can realize the measurement of the radiation source signal centre frequency of the unknown movement velocity only on the basis of the real-time frequency measurement technology. Moreover, the method can realize the detection of the frequency of the mobile ration source by adopting a short baseline, and is suitable to be used in various carriers such as vehicles, ships and warships, aircrafts and the like.

The invention belongs to the technical field of life prediction, and relates to a method for predicting crack initiation life of a high temperature alloy containing inclusion powder. The method comprises the steps of defining a damage variable field D(xi, N) describing the crack initiation process around inclusions; defining a characterization parameter; defining a cyclic characteristic parameterR; defining a damage variable field rate equation; predicting the crack initiation life. The invention provides the method for predicting the crack initiation life of the high temperature alloy containing the inclusion powder, and the method can predict the service life of powder high temperature alloy parts, establish a fatigue failure performance criterion for the powder high temperature alloy parts, and further provide a basis for safety assessment during process of aeroengine component design.

A method of controlling a dynamic physical system comprising a plurality of variable quantities. A model of the system comprising a plurality of variables representing the variable quantities, and a plurality of respective rate equations that describe the rate of change of the variables, is obtained. A control term in at least one rate equation from the plurality of rate equations is identified. A rate control function is derived from, for at least one of the variables in the rate equation, the proportion of the variable to the growth rate of the rate equation, and the rate control function is applied to the control term to provide a stabilised control term. The dynamic physical system is then controlled by modifying at least one of the quantities represented by the variables in the control term, so that the control term derived from the modified quantities is substantially the same as the stabilised control term.

A method for increasing production in a reservoir, comprising performing a swabbing test at a depth in a pipe, wherein the pipe is located in a wellbore and wherein a portion of the wellbore is located inside the reservoir, periodically measuring, during the swabbing test, pressure in the bottom portion of the pipe using the pressure gauge to obtain a plurality of pressure measurements, wherein the pressure gauge is affixed to an inner wall of a bottom portion of the pipe, and determining a plurality of flow rates of fluid flowing from the reservoir through perforations in the wellbore into the pipe using a flow rate equation and the plurality of pressure measurements.

Method for measuring the come-and-go loss in the cavity of LD pumping solid laser. The procedures are: first determining the relationship between the laser power and the pumping power measured from the experiment; which experiment result is then substituted in the rate equation to proceed numerical equating to determine the loss in the cavity; in the rate equation, considered are the laser oscillation and other transition steps which affecting the running of a laser, and considering the pumping light and laser being all Gaussian distribution. This invention method is particularly suitable for measuring the come-and-go loss in low gain microchip solid laser cavity.

A method for obtaining the binding kinetic rate constants using fiber optic particle plasmon resonance (FOPPR) sensor, suitable for a test solution with two or more concentrations, which employs the following major steps: providing one FOPPR sensor instrument system, obtaining optical time-resolved signal intensities starting at the initial time to the steady state of the two or more regions, substituting the measured signal intensity values into the formula which is derived by using the pseudo-first order rate equation model. In addition, this method measures the temporal signal intensity evolution under static conditions as the samples are quickly loaded. As a result, unlike the conventional device where the sample is continuously infused, the method is able to measure the association and dissociation rate constants of which the upper bounds are not limited by the sample flow rate.

The invention discloses a modeling method for an in-furnace ash deposition model based on direct simulation of Monte Carlo, and belongs to the field of in-furnace ash deposition predication of thermal power plants. The method comprises the following steps that 1, a computational fluid dynamics method is used for calculating a flow field near an ash deposition sampling point; 2, flow field conditions obtained through calculation are imported into a particle motion equation; 3, a direct simulation Monte Carlo method is adopted for calculating collisions among flying ash particles; 4, wall heat flux is provided through a sampling gun, then a flying ash adherence rate equation is solved, and the deposition process of the flying ash particles on a sampling face is calculated. The calculation result indicates that the constructed in-furnace ash deposition model can accurately predict the deposition rate of the flying ash particles in a furnace, detailed ash deposition inner layer flying ash particle size distribution is given, and dynamic prediction of the in-furnace ash deposition process is successfully achieved.

The invention discloses a wind field reconstruction method based on compressive sensing.A calculation model is a wind field, the two sides of the wind field are affected by the boundary, and a boundary layer will be generated.The X direction is a horizontal direction, the y direction is the direction where wind passes the wind field, the wind speed direction is perpendicular to an inlet, wind enters the wind field in the y direction, after the inlet wind speed changes, influences on the field are calculated, speed fields generated before and after the inlet wind speed changes are compared, a field with peak value areas will be obtained at a certain moment when disturbance is pushed forwards, most points of the field are in the net added-value state, a computational area performs computation through theories such as the Bell operation, a mass conservation equation, a momentum conservation equation and a turbulent kinetic energy and turbulent kinetic energy dissipation rate equation, and sparse treatment is performed on a matrix by means of a proper wavelet basis.The method can be used for fast predicting the wind field, and data on lots of grids are reconstructed through little calculation.Operation time is shorter compared with that of a traditional prediction method.

The invention belongs to the field of oil and gas well building safety and particularly relates to a real-time early warning method for the casing abrasion risk. The real-time early warning method ischaracterized in that firstly, the maximum lateral force between a drill rod joint and a casing is selected through calculation, the abrasion time is determined through the drilling rate equation, andthe abrasion area and depth of the casing are obtained; then the residual internal pressure strength and the residual collapsing strength of the casing are obtained, the residual internal pressure resistance safety factor and the residual collapsing resistance safety factor of the casing are calculated, and according to the obtained residual internal pressure resistance safety factor and residualcollapsing resistance safety factor of the casing, the risk grade is divided; and finally, according to the risk grade, the casing abrasion situation is determined, and real-time early warning is conducted. The real-time early warning method has the advantages that the abrasion depth of the casing at the maximum abrasion risk position can be calculated according to the well track, the abrasion quantities of the casings in current drilled and to-be-drilled wells can be pre-evaluated, and thus casing protection measures are advantageously taken in the later period.

In order to solve the technical problems that the existing method for testing the velocity field parameters of a test flow field of a hypersonic aircraft needs to broadcast tracer particles to the flow field, so that a tracer particle broadcasting system needs to be additionally designed, and the tracer particles are difficult to ensure to be efficiently mixed with the test flow field of the hypersonic aircraft, so that the following performance and the distribution uniformity of the tracer particles are poor, the invention provides a method for testing the velocity field parameters of the test flow field of the hypersonic aircraft. The method provided by the invention is improved in that: based on a Kelvin-Helmholtz critical nucleation radius equation, a nucleation rate equation and a Dobbins liquid growth model, water vapor in an incoming air flow is condensed in a test flow field to form condensed droplets with the particle size of 1-10 micrometers, and the condensed droplets are used as tracer particles for velocity field measurement. The method does not need to scatter special tracer particles into the flow field, so that a corresponding tracer particle scattering system doesnot need to be additionally designed, thereby reducing the test cost and avoiding the problem of scattering special tracer particles into high-temperature and high-pressure pipelines.

The invention discloses a nondestructive grading method for lamb carcass output. The method, which is implemented on the basis of a near-infrared side meat thickness prediction model, includes the following steps: (1) acquiring the near-infrared spectrograms of the side meat thickness-measured parts of lamb carcasses to be graded; (2) preprocessing and introducing the acquired near-infrared spectra into the near-infrared side meat thickness prediction model, so that side meat thickness values are worked out; (3) combining the side meat thicknesses, a carcass meat rate equation of the near-infrared side meat thickness prediction model and an output-grading method to carry out the nondestructive grading of the carcasses. A near-infrared side meat thickness prediction model construction method includes the following steps: (1) measuring the side meat thickness values of the different lamb carcasses; (2) acquiring the near-infrared spectrograms of the side meat thickness-measured parts of the different lamb carcasses; (3) preprocessing and then correlating the acquired near-infrared spectra with the measured side meat thickness values to construct a mathematical model. The method does not need to injure the lamb carcasses, analysis is rapid and simple, and the method provides quick initial grading preparation for mutton-processing enterprises in China.