430 results about "Balance equation" patented technology

The invention relates to a method and system for establishing a multilayer oil pool inter-well connectivity model. The multilayer oil pool inter-well connectivity model capable of simulating oil and water dynamic states is established oriented to the limitation that by means of a current connectivity model, only the dynamic change of production liquid can be predicted, the dynamic states of the oil phase and the water phase cannot be calculated respectively, and connectivity analysis cannot be carried out layer by layer. According to the model, an oil pool system is layered and scattered into a series of inter-well communication units, matter balance equation calculation is carried out with the inter-well communication units as simulating objects, pressure solving and inter-well flow calculation are achieved, an inter-well saturation degree tracking calculating method is established with the combination of the lead edge boosting theory, and the output dynamic states of oil and water of all layers at well points are obtained; a model parameter inversion method is established in a fitting mode through dynamic states based on a random disturbance approximation method, a projection gradient method and the like. Layered inter-well flow distribution coefficients, single well longitudinal production liquid and production oil splitting coefficients and other information can be obtained in real time, the oil pool plane, the longitudinal oil and water flow relation and the production measure change can be more accurately reflected to guide the practical production of an oil field.

A Software Engine that summarizes the financial state of a business in a single hierarchical tree data structure. The root node of the tree is the balance equation of accounting, its leaf nodes are the ledger accounts of the company, and its internal nodes represent all of the sums required in preparing the balance sheet, the income statement, and the retained earnings statement. Each non-leaf node obtains its financial balance from its child nodes. Since the Income Summary and Retained Earnings are non-leaf nodes, they do not have to exist as separate ledger accounts and their respective child nodes do not need to have their balances closed and transferred to them—all accounts have a permanent (non-temporary) balance. The difference between two trees produces the income and earnings retention of the business.

The invention discloses a method and a system used for determining well control dynamic reserves of a shale gas well. The method comprises the steps of obtaining an initial formation pressure of a shale gas reservoir, and calculating a well bottom flow pressure through structure data and production data of the gas well; establishing a first interpolation table based on a conversion relationship between a pressure and a pseudo-pressure to establish a corresponding relationship between the pressure p and the pseudo-pressure m(p); establishing a second interpolation table based on given basic parameters and Za(p) defined by a matter balance equation of the shale gas reservoir to establish a corresponding relationship between the pressure p and a ratio of the pressure p to Za(p); and based on the initial formation pressure, the well bottom flow pressure and the production data, determining the well control dynamic reserves of the shale gas well by adopting the first interpolation table, the second interpolation table and a productivity equation. According to the method and the system, a shut-in pressure is not needed to recover an evaluated average formation pressure in calculation; and a calculation result is suitable for various applications such as reasonable shale gas well production allocation, reasonable development technology policy making, development scheme optimization and the like.

The invention provides a vertical landing track design method for an unmanned aerial vehicle, which belongs to the field of flight control and comprises the following steps of: 1, building a balance equation of the unmanned aerial vehicle landing stability state according to the kinematics relationship of the unmanned aerial vehicle; 2, adopting a non-linear plan method for designing the verticallanding track of the unmanned aerial vehicle in a glissade stage; 3, designing the height track in an index form in a leveling stage and solving the non-linear equation to obtain the vertical landingtrack of the unmanned aerial vehicle according to the designed track angle trimming value and the elevation instructions in the leveling stage; and 4, integrating the landing tracks in the glissade stage and the leveling stage to obtain the vertical landing track of the whole unmanned aerial vehicle. The method has the advantages that the safety margin of the incidence angle and the operation margin of an elevator are improved, the precise and safe landing of the unmanned aerial vehicle is convenient to guide, the method is applicable to the landing control algorithm considering all of the height, the pitch angle and the descending speed, in addition, the landing performance is fully analyzed, and mathematic software is adopted for effective design to avoid the traditional experience trial and error.

The invention provides a ship intelligent obstacle avoidance method based on an artificial potential field. The method comprises a step of collecting ship information, inland waterway information andobstacle information in real time, a step of establishing an inland waterway coordinate system based on the collected information and establishing a waterway boundary repulsion potential field model and an obstacle repulsion potential field model based on an artificial potential field method, a step of establishing a balance equation according to composite field effect formed by superposing a waterway boundary repulsion potential field and an obstacle repulsion potential field borne by a ship during the processing of navigation, carrying out solution to obtain position points which the ship isabout to pass in intelligent obstacle avoidance, and fitting the position points to obtain an obstacle avoidance route, and a step of controlling the heading and speed of the ship according to the obstacle avoidance route. According to the method and the system, a practical support is further provided for the realization of the ship intelligent obstacle avoidance, and the probability of collisionwith an obstacle is greatly reduced.

The invention discloses a dynamic control method of a linear steering engine electric loading system, comprising the following steps: modeling a servo loading motor, constructing a torque balance equation, and constructing a linear steering engine mechanism model; building a ball screw pair motion model; analyzing the transfer function of the electric loading system, designing a three-closed-loop control method based on a current inner loop, a position outer loop and a force outer loop, and applying complex vector PI control in the current inner loop to enable the current of the servo loading motor to track instruction signals quickly and accurately; and finally, making feed-forward compensation for angular velocity, and verifying the control method. The method takes an electric loading system driven by a permanent magnet synchronous motor as a specific object, and considers the impact of the characteristics of the linear steering engine and the coupling degree between the linear steering engine and the electric loading system. The active force of active displacement of the linear steering engine is inhibited, and the loading precision of the linear loading system is improved. Moreover, a verification method is put forward, which makes a linear load simulator better evaluated.

The invention provides a coaxial rigid rotor coupling pneumatic elastic response analysis method, and belongs to a helicopter kinetic analysis technology. The method is characterized in that according to the operation and control characteristics of a coaxial rigid rotor helicopter, a balance equation optimization solution method is built, and an optimization solution is found according to the given target and constraint conditions. According to the characteristic of complicated coaxial rigid rotor flow field environment, a rotor flow field is calculated by using a computational fluid dynamic method based on an Euler/N-S equation; and then, the coupling pneumatic elastic response is calculated by using a computational fluid dynamic/computational structural dynamic loose coupling analysis method. The coaxial rigid rotor coupling pneumatic elastic analysis method has the advantage that when the analysis method is used, balance operation and control parameters, blade response, rotor loads and the like of the coaxial rigid rotor helicopter can be calculated. The method has good analysis precision and engineering applicability; the relying of the development process on the test can be reduced; and the design period and the development cost can be greatly reduced.

The invention discloses a method for calculating a non-steady state yield of a volume fractured horizontal well of a shale gas reservoir. The method comprises the following steps of dividing the reservoir into a volume fractured region and a non-transformed matrix region, and collecting basic parameters of the volume fractured region, the non-transformed matrix region and the horizontal well, wherein the volume fractured region is Darcy flow, and the non-transformed matrix region is Knudson flow; according to a mass conservation law, establishing a steady-state yield formula of the volume fractured horizontal well of the shale gas reservoir; based on a pressure propagation formula, the steady-state yield formula and a matter balance equation, calculating the non-steady state yield of the volume fractured horizontal well of the shale gas reservoir by applying a continuous quasi-steady method; and repeating the previous step, and performing calculation to obtain the non-steady state yield of the volume fractured horizontal well of the shale gas reservoir. The method fully considers a process that a pressure is propagated to a boundary gradually in a production process of the volume fractured horizontal well of the shale gas reservoir, different seepage laws of shale gas in a volume transformation region and the non-transformed matrix region, and adsorption and desorption effects of the shale gas, so that actual conditions are better met.

The invention relates to a lower-bound limit analysis method of bearing capacity considering rock translation and rotation effects at the same time, and belongs to the technical field of rock slope stability analysis. According to the method, a rigid block unit is scattered as a geometry system of a rigid rock and a structural plane, the normal force, shearing force and bending moment of the structural plane are used as unknown quantities, a static permission stress field satisfying an equilibrium equation considering the translation and rotation effects of the rigid block unit, structural plane shear yield conditions, structural plane tensile yield conditions, structural plane rotational yield conditions and static boundary conditions is constructed, an overload coefficient is used as a target function, and a lower-bound linear mathematic programming model is built; the linear mathematic programming model is solved by means of an interior point algorithm, a strength reserve coefficient is solved by means of an iterative method at the same time, and the lower-bound solution and corresponding yield area of the overload coefficient or the strength reserve coefficient of the jointed rock slope are acquired. The method has the advantages that the concept is clear and the computational accuracy is high, and the method can be applicable to bearing capacity analysis of translational or rotational failure of the jointed rock slope.

The invention discloses a method used for determining shale-gas multistage-fracturing horizontal-well interior-and exterior-zone dynamic reserves. The method includes: establishing gas-well binomial productivity equation through gas testing materials, and calculating actual flowing bottomhole pressure (FBHP) through production data and gas-well structure parameters; respectively establishing matter balance equation of a fracturing transformation zone and a non-fracturing transformation zone for a multistage-fracturing horizontal well in considering of adsorption gas desorption and abnormal high pressure influence; respectively setting the dynamic reserves of the fracturing transformation zone and the non-fracturing transformation zone, adjusting the dynamic reserves by combining with the matter balance equation of the fracturing transformation zone and the non-fracturing transformation zone, interporosity flow equation between the fracturing transformation zone and the non-fracturing transformation zone and the binomial productivity equation, and determining the fracturing horizontal-well interior-and exterior-zone dynamic reserves. With the method, testing of average formation pressure by well shutdown is not needed during use, influence of adsorption gas desorption and abnormal high pressure as well as fracturing recombination zones can be considered, and the dynamic reserves of the fracturing transformation zone and the exterior non-fracturing transformation zone can be respectively determined.

The invention discloses an influence coefficient dynamic balance method on rotating machine with multiple plane, multiple-points and multiple revolving speed shafting. The influence coefficient dynamic balance method on rotating machine with multiple plane, multiple-points and multiple revolving speed shafting comprises the steps that 1, designating a shafting balancing revolving speed point, balancing planes and numbers of measured points; 2, an initial deflection value of a spindle and an initial vibration value are measured under a slow revolving speed of 300rpm; 3, a vibration response of the measured points on a bearing after trial mass is conducted on a plurality of balancing planes on the shafting; 4, the minimum value of the residual vibration amplitude epsilon of all vibration measured points after the rotor is balanced is set as a goal, a vibration response vector equilibrium equation is established, and a size and angel of a balance weight Q on the unit shafting are obtained; 5, the vibration value of all vibration measured points are read, the above steps 2, 3, and 4 can be repeated once the value is unsatisfied. The influence coefficient dynamic balance method on rotating machine with multiple plane, multiple-points and multiple revolving speed shafting has a overall consideration on vibration with multiple plane, multiple-points and multiple revolving speed shafting, and a seesaw phenomenon in the traditional dynamic balance process is effectively avoided.

The invention relates to an asymptotic variational method-based method for simulating and optimizing a composite material laminated plate, which belongs to the field of analysis of material mechanics. The method specifically comprises the following steps of: constructing a three-dimensional plate energy equation represented by a one-dimensional generalized strain and warping function on the basisof a rotation tensor decomposition concept; strictly splitting the original three-dimensional problem analysis into nonlinear two-dimensional plate analysis and cross-section analysis along a thickness direction on the basis of an asymptotic variational method; asymptotically correcting an approximate energy functional of a reduced-order model to a second order by using the inherent small parameter of the plate and converting the approximate energy functional into the form of Reissner model for practical application through an equilibrium equation; accurately reconstructing a three-dimensional stress/strain/displacement field by using an obtained global response asymptotic correction warping function; and optimizing the composite material laminated plate by using an optimization strategy of bending and torsion rigidity coefficients obtained by maximization cross-section analysis. The method has high practicability and high generality, and the resolving speed and efficiency of this type of problems can be remarkably increased.

Objects of the present invention is to improve the control accuracy of the SOC of the battery in consideration of the electric power losses of a plurality of motor generators and, in accordance therewith, to secure the protection performance of the battery and to increase the energy recovery efficiency according to the regeneration. In a drive control device of a hybrid vehicle including a motor torque instruction value calculating means, an electric power loss predicting means, an electric power upper limit/lower limit value calculating means, and a target electric power calculating means are arranged, and the motor torque instruction value calculating means calculates torque instruction values of a plurality of motor generators using a torque balance equation including target engine torque required at a target engine operating point and an electric power balance equation including target electric power.

The invention discloses a method for predicting the well yield of sealed, unsaturated oil reservoirs through elastic driving water-flooding extraction. The method includes: measuring the initial volume coefficient Boi of crude oil and the volume coefficient Bo of the crude oil under different pressure conditions, measuring the initial oil saturation Soi and the initial water saturation Swc of the rock core, generally measuring the in-place oil compression coefficient Co, the formation water compression coefficient Cw and the rock compression coefficient Cp, obtaining the rock effective compression coefficient Ceff according to the above parameters; measuring the oil geological reserves N and the reservoir pressure under a certain injection condition according to a matter balance equation, and finally measuring the yield of an oil well according to a plane radial flow Darcy equation, wherein the yield includes oil yield and water yield. The method supplements the correspondence between injected water and oil reservoir pressure change under the water-flooding extraction condition, accordingly can predict the daily oil yield and the daily water yield under the water-flooding extraction condition, and provides reference value for oil field production cost.

The invention discloses a load simulation method for a cataplane landing gear, and belongs to the field of strength design of the cataplane landing gear. The load simulation method mainly comprises the following steps: analyzing stress on the whole cataplane, a nose gear and a main landing gear of a cataplane, so as to establish a corresponding mechanic equilibrium equation; establishing a nose gear simulation analysis model, a main landing gear simulation analysis model and a whole cataplane dynamic simulation analysis model according to the nose gear mechanic equilibrium equation; finally, correcting the whole cataplane dynamic simulation analysis model according to testing gravity center data and a front main landing gear load curve during practical catapult launching of the cataplane. The corrected model is the model capable of being used for catapult launching load simulation of the cataplane, problems in load design and analysis of the landing gear during catapult launching of the cataplane are solved, and the flight test verification of a carrier-based aircraft in an aircraft carrier platform and a land-based training ground is guaranteed.

Aiming at the deficiencies of energy flow models, load cut-down models and reliability assessment indexes of the existing power-gas interconnection system reliability assessment, the invention discloses a power to gas (P2G) device-considered power-gas interconnection system reliability modeling method and an assessment method thereof. The method comprises the following steps of in an energy flow model, importing a wind power plant abandoned air volume, and consumed electric power and injected air volume in a P2G device model into an electric power system active balance model; adding a heat load cut-down amount and an abandoned air volume variable in a target function of an optimization model in the load cut-down model; and in a reliability assessment index, establishing a device-level index, for system reliability index contribution, of a P2G device.

The invention discloses a calculation method of a tilt corridor of a tilt four-rotor aircraft with periodic variable pitch at constant rotational speed, which comprises the following steps: establishing flight mechanics models of various parts of the aircraft, converting all forces and moments into a body shaft system, and establishing a six-degree-of-freedom balance equation; determining the tiltcontrol mode; solving the upper and lower boundaries of the pitch angle by taking the lift characteristics of the wing as the limiting factor; obtaining the control variables and attitude angles under different state conditions by optimal trimming; finding the corresponding wing lift characteristic limit minimum speed boundary and wing lift characteristic limit high speed boundary; obtaining theavailable power limiting high-speed boundary by solving the required power at different state points. The invention is based on a flight mechanics model, takes into account the parameters of each aspect of the aircraft design, and reflects the specific attributes of each feasible flight point. The invention is also applicable to the tilt corridor calculation of tilt four-rotor aircraft under different control modes.

The invention discloses a yawing motion control method of a four-wheel distribution type drive coach, and relates to the technical field of vehicle control. A layered control method is adopted, the upper layer is a motion tracking layer, steering response of a steady state of the vehicle is calculated by adopting a non-linear vehicle model and the reference understeer degree, meanwhile, a road attachment condition limiting value is adopted for constraint, and steady-state lateral force response and tire self-aligning torque response are calculated with a magic tire formula according to slip angle response at the steady state and vertical load change; needed additional yawing moment is calculated with a yawing motion balance equation; a lower layer is an actuator control layer, and generalized control force is reasonably distributed to four drive motors with an optimization algorithm through combination with the current driving condition; finally, offline distribution calculation results of different vehicle parameters needed on different upper layers are stored and looked up offline, four driving wheels are subjected to torque distribution according to road attachment conditions, yawing motion of the vehicle is controlled, and driving stability is guaranteed.

A fracture-vug type carbonate reservoir water breakthrough early warning method of the present invention relates to an oil well water breakthrough early warning method, and aims to determine the water invasion time timely, optimize a working system, prolong an oil well water-free oil production period, and improve the oil well recovery efficiency. The method of the present invention comprises the following the steps of S01 obtaining the oil pressure drop under different accumulative liquid volumes according to a matter balance equation, and drawing a relational graph of the oil well pressure drop and the accumulative liquid volume; S02 for the non-water breakthrough reservoir, if a oil well pressure drop and accumulative liquid volume curve deviates, explaining three possible phenomena: (1) the crude oil is degassed in a shaft or stratum; (2) a new reservoir is exploited; (3) the edge-bottom water begins to invade; S03 excluding the two situations that the crude oil is degassed in the shaft or stratum and the new reservoir is exploited to determine that the reservoir edge-bottom water begins to invade; S04 determining the water invasion time according to the relational graph of the oil well pressure drop and the accumulative liquid volume, and carrying out the water breakthrough early warning.

The invention provides a fracture-cavern type carbonate condensate gas well development index analyzing method and device. The method includes the steps of obtaining a standard parameter in a single well, calculating the dynamic reserve volume of the single well according to the standard parameter, determining the natural gas yield and natural gas accumulated yield of all production time points according to the preset natural gas yield segmented decreasing rule, determining the two-phase deviation coefficient and gas-oil ratio data according to PVT experimental data, establishing a matter balance equation, substituting the natural gas accumulated yield and the two-phase deviation coefficient into the equation, calculating stratum pressure theoretical values of all the production time points, conducting correction to generate a stratum pressure correction value according to actually-measured static pressure data, predicting the corresponding condensate oil yield according to the stratum pressure correction value and the gas-oil ratio data, calculating the condensate oil accumulated yield according to the matter balance equation with abandoned stratum pressure as a restraint, and calculating the condensate oil production degree and the natural gas production degree through the combination of the dynamic reserve volume of the single well.