9 results about "Darcy" patented technology

The present application relates to oil and gas field development technology, disclose a kind of heavy oil reservoir hot water drive limit well spacing determination method. Including the following steps: S1, the starting pressure gradient corresponding to different temperature is obtained by percolation experiment test;S2, according to the starting pressure gradient corresponding to different temperature, determine the inflection point temperature of starting pressure gradient curve;S3, based on the inflection point temperature of pressure gradient curve, the percolation area between injection well and production well is divided;S4, based on the percolation area divided, the percolation resistance R of darcy percolation area between injection well and production well is calculated d ;S5, based on R d The pressure drop ΔP of darcy percolation area between injection well and production well is calculated d ;S6, based on ΔP d The length l of non-darcy percolation area between injection well and production well is calculated nd ;S7, based on l nd Determine the limit well spacing L of heavy oil reservoir hot water drive. The determination method can guide the formulation of heavy oil reservoir hot water drive development plan, improve development effect.

The present application relates to the technical field of seepage mechanics, and particularly relates to a conical sealing surface leakage rate calculation method based on Darcy's law, comprising the following steps: a W-M function is used to simulate the random topography of the workpiece surface at a microscale, and a normalization method is used to generate surface point cloud data meeting roughness requirements; according to the surface point cloud data, a contact mechanics model is used to solve the change law between the contact state and the external load, and according to the Hertz contact theory, the contact between the rough surfaces is reconstructed as the contact between a rigid plane and a flexible rough surface; the surface is discretized into a three-dimensional grid model, the effective porosity is screened and calculated by using the connected domain discrimination method; a micro-leakage rate calculation method for the conical sealing surface in the flared pipe joint is obtained based on the effective porosity and the seepage mechanics theory algorithm; the leakage rate of the conical sealing interface is calculated, and the sealing performance of the interface is quantitatively evaluated. The present application improves the comprehensiveness and accuracy of the sealing performance evaluation.

The application discloses a metamaterial flow uniformity maintaining device, a preparation process and application. The metamaterial flow uniformity maintaining device comprises a transition part, a first maintaining part and a second maintaining part. The transition part is in an arc shape, and the radius satisfies R1 < r < R2. The transition part, the first maintaining part and the second maintaining part are all made of a metamaterial. In the embodiments of the application, a two-dimensional or three-dimensional flow uniformity maintaining device conforming to a condition formula for maintaining the flow uniformity in a variable channel obtained according to the Darcy law and corresponding boundary conditions is constructed. The device has sufficient theoretical basis and high reliability. The flow uniformity maintaining device can maintain the flow uniformity of fluid after the fluid passes through a contraction or expansion pipeline, reduces the pressure drop and resistance of the fluid in the flow process, and further guarantees the stability and uniformity of the fluid in the variable channel flow.

This invention provides a method for predicting the production capacity of electrically heated cold-drive heavy oil reservoirs using wellbore coupling, belonging to the field of oil and gas field development engineering technology. The method includes acquiring basic reservoir parameters and electrical heating parameters; solving for the reservoir temperature distribution at the current time step based on energy conservation; dividing isothermal zones into different temperature zones based on temperature; tracking the cold-drive front position using the Buckley-Leverett method to determine the friction saturation and production end saturation, and calculating the heavy oil production; combining the injection well pressure and friction saturation, solving for the injection-production pressure difference based on Darcy's law to obtain the bottomhole flowing pressure of the production well; inputting the bottomhole flowing pressure and temperature into the wellbore pressure drop model to calculate the wellbore pressure profile and temperature profile; iteratively updating until the end of the production cycle, and outputting the production capacity prediction result. This invention solves the problems of inaccurate predictions caused by existing models' single scenario, neglect of thermal-fluid coupling, and lack of wellbore coupling, and can accurately predict the production capacity of electrically heated assisted cold-drive heavy oil reservoirs.

This invention provides a method and system for calculating inter-well formation pressure after a shale gas platform is put into production. The method includes: calculating the recovery degree R based on EUR and the current cumulative gas production Gp; and calculating the average formation pressure P under the original conditions. i Gas deviation factor Z under original conditions i EUR and Gp are used to calculate P1; a ~R diagram is plotted and a binomial fit is performed to obtain the deviation coefficient σ; P'2 is the measured formation pressure, P'1 is the formation static pressure, Z'1 is the gas deviation factor corresponding to P'1, and Z'2 is the gas deviation factor corresponding to P'2; P2 is calculated based on σ and P1; in the later stage of production, shale gas wells reach the boundary control flow stage, utilizing the formation pressure p at the gas supply boundary. e The Darcy steady-state flow formula for radial flow in a fracturing plane describes the formation pressure p(r) at any distance from the well in the reservoir. The system described above can implement this method. This invention can calculate the formation pressure drop after production commences.

The application discloses a rock specific surface evaluation method based on gas well dynamic data, and comprises the following steps: S1, collecting and arranging gas well static data and gas well dynamic data; S2, using a Blasingame modern production harmonic decline graph board curve to extract a part meeting the Darcy seepage law, and recording a time period as [t0, t1]; S3, calculating an equivalent gas discharge radius and a gas well skin coefficient; selecting a subinterval [t'0, t'1], using an exponential decline model to carry out fitting, and calculating a decline rate; S4, establishing a rock specific surface model, and obtaining the rock specific surface by using the rock specific surface model. The application establishes a quantitative model of the rock specific surface, effectively avoids the limitation of a laboratory overburden condition; meanwhile, by means of well logging interpretation results and seepage mechanics theory, the rock specific surface calculation scale is expanded from a core scale to a large scale of a well logging interpretation series detection radius and a well control range, the rock specific surface model can reduce core analysis experiments, can reduce gas reservoir development cost from the economic aspect, and can improve gas reservoir development benefit.

This invention discloses a method for calculating the production rate of fractured wells in heterogeneous tight oil reservoirs considering the initiation pressure gradient. First, based on the closed boundary point source function, a multi-scale seepage model of matrix seepage in heterogeneous tight oil reservoirs is established using Green's formula and Newman integral. Then, according to the skin principle, a negative skin coefficient is introduced to describe the influence of the fracture network stimulation zone on seepage, resulting in a flow characterization model of the fracture network stimulation zone. Next, the main fracture flow equation is established, and the pressure drop equation of a single discrete fracture unit is described using Darcy's law. The pressure drop characterization model from any discrete unit to the horizontal wellbore is calculated using the pressure drop superposition principle, resulting in the main fracture flow characterization model. Finally, a production rate calculation model for fractured wells in heterogeneous tight oil reservoirs is coupled and established. The steady-state production processes of fracture micro-segments within each small time interval are superimposed, and a heterogeneity coefficient is established based on the skin principle, resulting in a production rate calculation model for fractured wells in heterogeneous tight oil reservoirs under variable production conditions. This method enables rapid and effective, precise prediction of production rates.

The application relates to the technical field of water conservancy and hydropower engineering, and discloses a dam foundation covering layer nonlinear seepage fine calculation method and system, which aims to solve the problem of poor accuracy and fineness of the existing method, and mainly comprises the following steps: constructing a seepage wall geometric model containing defects based on field drilling data and dividing the grid; based on the physical property parameters of the covering layer soil, the Darcy seepage coefficient and the Forchheimer seepage coefficient under the Darcy-Forchheimer model are calculated by using the Ergun formula; boundary conditions, fluid parameters and solution control parameters are configured, and the nonlinear seepage characteristic parameters of the covering layer soil and the seepage wall defects are specified to construct a fine analysis model; the seepage field numerical calculation is carried out based on the RANS equation and the Darcy-Forchheimer model by using a finite volume method solver; and the calculation results are extracted to obtain the nonlinear seepage field distribution containing the covering layer soil and the seepage wall defects. The application improves the accuracy and fineness of the dam foundation seepage calculation containing the seepage wall, and is suitable for two-dimensional seepage analysis or three-dimensional seepage analysis.

The present application relates to solid waste incineration working condition adjustment technical field, especially, it relates to a kind of solid waste incineration working condition intelligent sensing and self-adapting adjustment method, realize the direct quantitative sensing of combustion state in furnace, based on Darcy law calculation layer equivalent permeability, based on Stefan-Boltzmann law calculation local effective heat release flux, can reflect the air permeability and combustion intensity of layer in real time, fundamentally solve the problem of traditional parameter lag.Equivalent heat-pneumatic impedance factor is proposed as comprehensive working condition evaluation index, the coupling relationship of heat release and gas flow is uniformly represented, a scientific quantitative basis is provided for control decision, and the control precision is significantly improved.A double-layer control architecture of adaptive fuzzy neural network combined model predictive control is constructed, the former realizes the multivariate coordinated regulation of primary air, secondary air, feeding and speed of grate, and the latter realizes the precise predictive control of auxiliary burner, and the working condition stability and adjustment speed are greatly improved by the cooperation of the two.