Abstract: A method for simulating compositional and/or multiphase transfers between the porous matrix and the fractures of a fractured multilayer porous medium, which are respectively saturated by a distinct liquid phase and gas phase. The method comprises constructing a geologic model representative of the networks of natural fractures of the medium and converting this geologic model into an equivalent double porosity model. Diffusion of the gas phase between the fractures and the matrix is modelled considering that a gas-liquid front exhibiting a quasi-static equilibrium at the interfaces is established from an initial time and progresses at a velocity controlled by the diffusion transfers within each phase. The transfers involve the difference between the concentration within the phase and the concentration of equilibrium between the two phases, as well as a variable exchange distance expressed as a function of the matrix saturation.

Abstract: The present invention is directed to a method for allocating revenue or taxes to individual fluid streams commingled during an oil and gas production process, the method includes commingling fluid streams to produce a commingled fluid stream; (2) utilizing a process simulation model to predict a phase change of each fluid stream in the commingled fluid stream, wherein the process simulation model predicts the phase change of all the individual fluid streams in the commingled fluid stream the phase change of each individual fluid stream in isolation of the commingled fluid stream, the phase change of all the individual fluid streams in the commingled fluid stream absent a single fluid stream; and (3) determining the difference in phases between the calculated phase change of all the in individual fluid streams in the commingled fluid stream and calculated phase change of all the individual fluid streams in the commingled fluid stream absent a single fluid stream.

Abstract: The disclosure is directed to a computer-implemented method of representing fluid flow in a physical fluid reservoir. The method includes generating a mesh representation of the physical fluid reservoir having a plurality of mesh elements. Each of the plurality of mesh elements is representative of a regional portion of the fluid reservoir. The method further includes generating a matrix-based representation of fluid flow comprising matrix elements associated with a mesh element and selectively weighting the matrix elements based on fluid flow direction in the regional portion of the fluid reservoir represented by the mesh element associated with the matrix element.

Abstract: A method for forecasting performance for and characterizing the properties of a multilayer low permeability gas reservoir. The method includes a coupled well/reservoir predictive model that accounts for pressure drop between layers, allowing accurate, rigorous, and rapid forecasting of reservoir performance. The method provides estimates of individual layer properties such as in-situ permeability, skin factor, fracture half-length, fracture conductivity, drainage area, etc. by simultaneously history matching production data and production log data using the coupled well/reservoir predictive model.

Abstract: A method for creating a stratigraphic model is provided. A core is obtained from a wellbore and a detailed graphic core description is created. Wireline data, including a borehole image, is obtained for a cored interval corresponding to the core and processed into an interpretable borehole image. The core description is compared with the interpretable borehole image to create a catalogue of geologic image facies. The borehole image from the entire interval of interest is compared to the catalogue to create a preliminary pseudocore description. The interpretable borehole image is interactively examined and compared with the preliminary pseudocore description to create a master pseudocore interpretation. A second master pseudocore is developed for a second wellbore. A stratigraphic model, and subsequently a reservoir model, may then be created by correlating between the master pseudocores of the first and second wellbores.

Abstract: A method for updating a geological reservoir model by integration of dynamic data having application, for example, to petroleum reservoir development. An initial map (y) of petrophysical properties is constructed by means of a geostatistical simulator and of static data. Then an initial set of gradual pilot points (PPi) and at least one complementary set of gradual pilot points (PPc) are constructed. A combined set of gradual pilot points (PP(t)) is then constructed by combining these sets of gradual pilot points according to the gradual deformation method wherein at least one deformation parameter is a characteristic parameter of said pilot points (position and/or value). The initial map (y) is then modified, the deformation parameters are modified according to the dynamic data and the procedure is repeated until a stop criterion is reached and the geological reservoir model is updated by associating the map thus optimized with the grid of the model.

Abstract: A Gas Reservoir Evaluation and Assessment Tool utilizes an Analytical Engine to produce predictions of pressure values and other production data at any point in space and at any point in time in a reservoir. A computer system, such as a workstation, stores a Gas Reservoir Evaluation and Assessment software which includes the Analytical Engine and responds to input data (which includes a reservoir description and fluid properties) by generating an output record which represents a prediction of the pressure values and other data at ‘any point in space’ and at ‘any point in time’ in a reservoir.

Abstract: A method is provided for evaluating the performance of a plurality of oil wells which were established to produce from a common reservoir beneath the earth's surface. The method comprises inputting information about the reservoir into a computer and establishing a time interval and time steps within that time interval over which performance of the wells will be evaluated. The total oil which is accessible clearing each time step in each time interval is determining, and then individual recovery factor for each time step is determined. A composite recovery factor is determined using the individual recovery factors, and the composite recovery factors are normalized to the best well in the field.

Abstract: A method of determining fluid phase distribution comprises receiving a plurality of oriented probe data; grouping the oriented probe data based on a depth interval; processing the grouped probe data; and generating fluid phase distribution information based on the processed result.

Abstract: A method with application for evaluation or production of a reservoir for determining multiphase flow parameters of a porous medium such as a rock, from the interpretation of displacement experiments. From an injection experiment on a rock sample, the saturation profiles are measured in different sections of the sample. The experimental data are then subjected to a preliminary interpretation by means of a numerical simulation code allowing production of simulated pressure profiles. These profiles are then combined with the measured saturation profiles so as to evaluate the local properties of the sample in terms of capillary pressure. These properties are then re-injected into the simulator as input data so as to finely interpret the flow parameters while respecting the evolutions of the differential pressure, of the displaced fluid production and of the saturation profiles.

Abstract: The invention is a method for simulating one or more characteristics of a multi-component, hydrocarbon-bearing formation into which a displacement fluid having at least one component is injected to displace formation hydrocarbons. The first step of the method is to equate at least part of the formation to a multiplicity of gridcells. Each gridcell is then divided into two regions, a first region representing a portion of each gridcell swept by the displacement fluid and a second region representing a portion of each gridcell essentially unswept by the displacement fluid. The distribution of components in each region is assumed to be essentially uniform. A model is constructed that is representative of fluid properties within each region, fluid flow between gridcells using principles of percolation theory, and component transport between the regions. The model is then used in a simulator to simulate one or more characteristics of the formation.

Abstract: A method for simulating water-hammer waves in a borehole is used to estimate formation parameters such as porosity and permeability, and to design completion strings. The simulation method uses a model that has a plurality of layers, at least one of the layers includes radial layering. Determined formation properties from analysis of the waterhammer are used in development operations.

Abstract: Fluid diversion measurement systems and methods are described. One system includes a section of tubular having a main flow passage and a fluid diversion port, the section of tubular adapted to be either moving or stationary during a fluid diversion operation, at least two sensors in the section of tubular, at least one sensor located upstream of the fluid diversion port and at least one sensor located downstream of the fluid diversion port, each sensor adapted to measure a parameter of a fluid diverted into a wellbore through the fluid diversion port; and means for using the measured parameters in realtime to monitor, control, or both monitor and control diversion of the fluid. This abstract allows a searcher or other reader to quickly ascertain the subject matter of the disclosure. It will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: A method and system for providing hydraulic modelers with the ability to accurately produce a surface representation of flow data that incorporates transitional elements in the underlying gravity hydraulic network is provided. The method includes triangulating surface techniques and smooth surface techniques that employ functions that enforce rules that preserve monotonicity as well as to preserve Q=0 when TW=HW. The value of Q can be calculated as well as the partial derivatives in the TW and HW directions for a point of interest. A smooth surface interpolation of the data, which maintains the above-noted conditions, and allows the quick evaluation of flow for any point in the data set, is provided.

Abstract: A method and system for development of a naturally fractured formation may include generating a fracture model from a fracture treatment of a well in the naturally fractured formation. The fracture model may account for natural fractures in the naturally fractured formation. The fracture model may include the fracture volume of the fracture generated by the fracture treatment. Well spacing and fracture stimulation design for one or more wells in the naturally fractured formation may be determined based on the fracture model.

Abstract: A method to determine water saturation of laminated sand-shale formations based on measurements of formation and shale resistivity anisotropy, the fraction of shale, and the porosity.

Abstract: A selectively reduced bi-cubic interpolation on quadrilateral grids for level set re-distancing improves finite-difference-based ink-jet simulation. The “bi-cubic” nature of the interpolation helps the scheme conserve droplet mass. The “selectively reduced” logic prevents the higher-order simulation algorithm from introducing new instability factors.

Abstract: A consistent back pressure formulation is introduced into ink-jet simulation models and algorithms to solve an instability problem that occurs as the head of an ink droplet reaches the end of the solution domain during simulation. The consistent back pressure formulation is obtained in a way that is consistent with the idea of interface smearing. Formulas for calculating the pressure boundary condition on quadrilateral grids are disclosed. An ink-jet simulation example is given to demonstrate the improved models and algorithms.

Abstract: Apparatus and method for monitoring a prostate in a human body in which a fluid flows and which is characterized by a change in the prostate with time in space for the purpose of diagnosing a prostate condition, particularly cancer. A preselected place in the prostate is monitored to collect data at two or more time points correlated to a prostate event. The data is indicative of a prostate parameter that varies with time as a function of at least two variables related to prostate wash-in and wash-out behavior. A calibration map is made on a calculated basis with each pixel or voxel representative of a color hue indicative of wash-out behavior and a color intensity indicative of wash-in behavior. When a satisfactory map is obtained, the collected data is processed on the basis of the map to obtain an image of the preselected place with each spatial unit thereof correlated with a color hue and a color intensity. Software and a data processing system are provided to develop the calibration map.

Abstract: Disclosed herein are systems and methods of hydrocarbon detection based on wavelet energy absorption analysis. One disclosed hydrocarbon detection method embodiment includes: a) obtaining seismic trace data for a region of interest; and b) processing the seismic trace data to determine at least one wavelet energy absorption factor as a function of position within the region of interest. Another disclosed hydrocarbon detection method embodiment includes: a) receiving from a user an indication of a region of interest in a seismic data set; and b) generating a display of wavelet energy absorption anomalies within the region of interest. One of the disclosed system embodiments includes a memory and a processor. In this system embodiment, the memory stores hydrocarbon detection software that, when executed by the processor, configures the processor to determine at least one wavelet energy absorption factor from seismic trace data.

Abstract: There is a method of determining properties relating to an underbalanced well, comprising inducing pressure variations in a fluid within a well, measuring the pressure variations, and calculating pore pressure of at least one fluid-producing formation. The pressure variations cause a change in flow rate from formations along a length of borehole, and as such a change in the production flow rate of the well. The variations in pressure are used to calculate the pore pressure. Variations in annular bottomhole pressure are induced by altering the flow rate of drilling fluid, or the density of drilling fluid or by acoustic pulsing downhole. The pore pressure, permeability and porosity of the formations is derived as a real time profile along the length of the borehole.

Abstract: Systems for implementing methods for generating platform location sets comprising selecting a set of platform locations; determining additional platform locations to add to the set of platform locations; validating the additional platform locations, and determining an optimum location for each platform location in the set of platform locations.

Abstract: A method of determining fluid flow in a volume containing two or more fluid components, including determining a pressure field for the volume. One or more streamlines are determined from the pressure field, and the fluid composition is solved for the fluid composition along the, or each, streamline. The pressure may also be solved along the, or each, streamline. The step of solving along the, or each, streamline may be performed using a finite difference technique.

Abstract: Methods for finite-difference-based inkjet simulation enable more precise control of ink droplet size and shape. A discrete transformation (mapping) is constructed so that a quadrilateral grid in physical space is transferred to the uniform square grid in a computational space. Since the grid in the computational space is square, numerical finite difference differentiation can be easily done. Governing partial differential equations, including a viscosity term, a surface tension term, and a level set convection equation for two-phase flows, are derived on the quadrilateral grid and then transformed to the computational space for application on the uniform square grid. A stable and powerful numerical algorithm is developed to solve the derived and transformed equations to enable finite-difference-based ink-jet simulation.

Abstract: A system, method, and software for optimizing the commingling of well fluids from a plurality of producing subsea wells. The mixing temperature and water content in each header of a collection manifold are calculated for each subsea well and header combinations, responsive to data from sensors at the collection manifold. Combinations with conditions outside operational limits are then discarded. Remaining combinations are ranked based on predetermined optimization criteria. The ranked combinations are provided for the operator for optimizing flow properties and well fluid production. The calculations can restart with new, real-time sensed values from the subsea collection manifold.

Abstract: An evaluation system models water usage within a region. The evaluation system provides a graphical representation of various water system components. Each water system component has a model describing its water balance and parameters for customizing the model for an instance of the water system component. The evaluation system receives indications of water system components within the region along with connections between the water system components. The evaluation system receives values for parameters of the water system components. The evaluation system then calculates the water demand of the region by calculating the water balance of each water system component within the region based on the models for each water system component and the connections between the water system components. The evaluation system provides a cost-effective solution to manage water usage within the region.

Abstract: Methods and systems for reservoir targeting, the systems implementing methods comprising filtering a plurality of values in a three-dimensional model to eliminate values which are below a threshold to create a filtered three-dimensional model; developing a first matrix from the filtered three-dimensional model representing a two-dimensional model of the reservoir, wherein the first matrix includes a plurality of cell center locations, cell areas, and the plurality of values; developing a second matrix from the first matrix using a distance-weighted sum of the plurality of values; and selecting target locations from the second matrix based on the distance-weighted sum of the plurality of values.

Abstract: A method for providing production optimization of reservoir completions having a plurality of completed intervals via available production analysis and production logging data provides a quantitative analysis procedure for reservoir and fracture properties of a commingled reservoir system, that includes the steps of measuring pressure for specific zones in a reservoir; selecting a pressure traverse model; computing midzone pressures using the traverse model; comparing the computed midzone pressures with the measured pressures; and modeling the bottomhole pressure of the reservoir based on the traverse model.

Abstract: A modelling method having application to petroleum production, soil cleaning, etc. for optimizing faster and more realistically the displacement conditions, in a porous medium wettable by a first fluid (water for example), of a mixture of fluids including this wetting fluid, another, non-wetting fluid (oil for example) and a gas.

Abstract: A grid convergence solution computation system computes a computed value (Ahigh) Of high-order accuracy, using a single grid, computes a computed value (Alow) of low-order accuracy, using the same single grid, and computes a grid convergence solution based on the relation between the computed value (Ahigh) of high-order accuracy and the computed value (Alow) of low-order accuracy on an assumption that the relation between the computed value (Ahigh) of high-order accuracy, the computed value (Alow) of low-order accuracy, and the grid convergence solution (Aconv) is substantially constant regardless of fineness or coarseness of the grid. The grid convergence solution computation system computes a highly accurate grid convergence solution (Aconv) by using small computational complexity.

Abstract: A Gas Reservoir Evaluation and Assessment Tool utilizes an Analytical Engine to produce predictions of pressure values and other production data at any point in space and at any point in time in a reservoir. A computer system, such as a workstation, stores a Gas Reservoir Evaluation and Assessment software which includes the Analytical Engine and responds to input data (which includes a reservoir description and fluid properties) by generating an output record which represents a prediction of the pressure values and other data at ‘any point in space’ and at ‘any point in time’ in a reservoir.

Abstract: The internal properties of a water-lain sediment body can be determined from the shape of the deposit. One method comprises solving equations relating the shape of a sediment body to the flow field that produced the body and using the flow field to solve for the sediment body properties in at least one point within the body. The flow field properties include flow velocity, suspended sediment volume fractions, deposition time, and flow height. The properties of the water-lain sediments include, in addition to the flow properties associated with deposition of the sediments, the thickness of the sediment body, the size of the body, the shape of the body, and the grain size distribution at points within the body.

Abstract: A method of measuring a water effect on an underground non-water well includes the steps of assembling a history of water cut (WC) measurements for the well over an extended period of time, determining a water cut rate of change (R) for the well based upon the history of water cut measurements, wherein the water cut rate of change is defined as follows: ? ( WC ) ? ( t ) = R , and identifying whether an anomaly exists based on the determined R.

Abstract: A method for determining formation pressure at a depth region of formations surrounding a borehole, including: keeping track of the time since cessation of drilling at the depth region; deriving formation permeability at the depth region; causing wellbore pressure to vary periodically in time and determining, at the depth region, the periodic and non-periodic component of pressure measured in the formations; determining, using the time, the periodic component and the permeability, the formation pressure diffusivity and transmissibility and an estimate of the size of the pressure build-up zone around the wellbore at the depth region; determining, using the time, the formation pressure diffusivity and transmissibility, and the non-periodic component, the leak-off rate of the mudcake at the depth region; determining, using the leak-off rate, the pressure gradient at the depth region; and extrapolating, using the pressure gradient and the size of the build-up zone, to determine the formation pressure.

Abstract: The present invention provides a method of combining various types of data and software in order to arrive at a composite graphical representation of a construction site, including surface and subsurface features. A 2-D or 3-D graph of subsurface contoured surfaces is created. A 3-D wire-frame model of surface and subsurface features is created. Aerial photographs of the site can be incorporated and the aerial photographs contoured surfaces and wire-frame model are to produce a complete Visual Reduction Modeling Language (VRML) model of both surface and subsurface features. The VRML model allows the user to identify and visualize a relationship between sub-surface features and above ground features.

Abstract: Process for the location of the position of the interface (5) between two fluids (f1, f2) each contained in a zone (7-1, 7-2) of a reservoir (4) in which: a) a reference transient flow condition that produces a reference pressure difference (?Pref(t)), is initiated in a reservoir (4) that comprises at least one pressure sensor (8) located within one of the zones (Z1), b) later an effective transient flow condition that produces a pressure wave which propagates within the reservoir (4) producing an effective pressure difference (?Pu1?(t)) is initiated, c) the pressure differences (?Pref(t)), (?Pu1(t)) are compared, d) a point in time (?1) that represents the instant when the pressure wave reaches the interface (5) between the two fluids (f1, f2) is determined, the distance (L1) between the interface (5) and the pressure sensor (8) is calculated. The operations b) to d) are repeated in order to monitor movement of the boundary. Application in the petroleum industry.

Abstract: Disclosed is a system and method for directing data representing well operations (drilling and producing) through the Internet or similar wide area network. The instant invention comprises a system and method of installing sensors at the well to provide technical information to remotely-located Internet users who provide services to the well owner. The service providers may be observers, who may then advise the well owners and operators as to actions to take to increase or optimize well performance. Service providers may also be data storage companies, who clean and store the data from the well. Service providers may then be paid from a portion of the well revenues or a portion of the incrementally-increased revenues.

Abstract: The present invention discloses a method for finding and analyzing underground magnetic anomalies. The method includes measuring magnetic signatures of the magnetic anomalies, interpreting the magnetic signatures to determine that the magnetic signatures are magnetic signatures of an underground fluid source, and determining at least one characteristic of the underground fluid source from the magnetic signatures.

Abstract: A gas flow meter having a gas flow detection circuit for detecting a current flowing through a resistor installed in a gas passage and a voltage generated across the resistor and outputting a voltage signal representing a gas flow passing through the gas passage; a noise reduction circuit for reducing external noise; and a digital adjusting circuit for digitally adjusting a signal representing the detected gas flow and outputting the adjusted signal; wherein a voltage signal based on the signal adjusted by the digital adjusting circuit is output.

Abstract: A modification to the Coates-Timur relationship to produce a more coherent relationship applicable to carbonate formations is disclosed. In this method, permeability may be determined using porosity and the ratio of bound fluid volume to (1—bound fluid volume). This method also allows for improved estimation of irreducible water saturation of a carbonate formation using the ratio of kc and (e?f+kc). Likewise, the bound fluid volume of a carbonate formation may be determined using the ratio of ?kc and (e?f+kc). In these relationships, e, x, and f are constants according to the following relationships e=xc, f=bc+1, x is between 1 and 100 mD (preferably 10 mD).

Abstract: A method for chemical analysis of fluids utilized in hydrocarbon exploration and production in which microfluidic systems designed to react to specific characteristics of a fluid are introduced into fluid samples or during operations. The microfluidic systems are then recovered and subjected to analysis to permit one to measure the desired characteristics.

Abstract: A method for modelling flows in a fractured medium crossed by a network of fluid conducting objects of definite geometry but not homogenizable on the scale of each grid cell of the model (large fractures, sub-seismic faults for example, very permeable sedimentary layers, etc.) which has an application in the evaluation of hydrocarbon reservoirs is disclosed. The method allows simulation fluid of flows in a fractured porous geologic medium of known structure that is discretized with a grid and modelled by considering that each elementary volume of the fractured geologic medium is an equivalent fracture medium and matrix medium on the scale of each cell between which fluid exchanges are determined. The method determines exchanges between the matrix medium and the fracture medium, and modeles the transmissivities of the various cells crossed by each conducting object, so that the resulting transmissivity corresponds to the direct transmissivity along each conducting object.

Abstract: The properties of a water-lain sedimentary deposit may be predicted at any location from a contour of constant deposit thickness. One embodiment of the method comprises (a) determining an outline of constant deposit thickness in a measured deposit, (b) determining the fluid flow properties at the inlet of the measured deposit, (c) determining a property of the deposit at any point inside the deposit from modeling the fluid flow. The properties of the deposit at any point may include the thickness of the sediment body, the size of the body, the shape of the body, and the grain size distribution at each point within the body, and any combination thereof.

Abstract: A method and apparatus for designing, monitoring or evaluating the growth of a subterranean hydraulic fracturing procedure is disclosed. The method uses techniques of analysis that are both accurate and efficient in reducing computing resources needed to process data. A computer generated method of estimation is used to determine the dimensions and shape of the hydraulic fracture. The estimate facilitates subsequent changes in fracturing parameter selection and design to maximize well performance and production. A rigorous method of evaluation is disclosed for a multi-layered or laminated petroleum reservoir. Material balance of hydraulically pumped fluids and proppant is maintained. In addition, the energy balance between the hydraulic fracture tip and the surrounding reservoir host rock is conserved.

Abstract: A method is disclosed for modelling fluid flows in a fractured multilayer porous medium by accounting for the real geometry of the fracture network and the local exchanges between the porous matrix and the fractures at each node of the network, thus allowing simulation of the interactions between the pressure and flow rate variations in a well running across the medium. The method essentially comprises discretizing the fractured medium by means of a mesh pattern, with fracture meshes centered on nodes at the various intersections of the fractures with each node being associated with a matrix volume, and determination of the flows between each fracture mesh and the associated matrix volume in a pseudosteady state. The method can be applied in hydrocarbon production well testing.

Abstract: The present invention relates to obtaining the analytical closed form solution to mean and variance in heat flow by solving the stochastic heat conduction equation incorporating randomness in the thermal conductivity. The method of the present invention has a wide range of applications in quantifying the thermal State of the crust and in obtaining closed form expressions for subsurface heat flow structure along with its error bounds. The exact formulae used in the invention can be used to better evaluate the thermal state for related oil and natural gas applications and also in tectonic studies and in studies related to the crystallization of minerals.

Abstract: A method is provided for scaling up permeabilities associated with a fine-scale grid of cells representative of a porous medium to permeabilities associated with an unstructured coarse-scale grid of cells representative of the porous medium. An areally unstructured, Voronoi, computational grid is generated using the coarse-scale grid as the genesis of the computational grid. The computational grid is then populated with permeabilities associated with the fine-scale grid. Flow equations are developed for the computational grid, the flow equations are solved, and inter-node fluxes and pressure gradients are then computed for the computational grid. These inter-node fluxes and pressure gradients are used to calculate inter-node average fluxes and average pressure gradients associated with the coarse-scale grid. The inter-node average fluxes and average pressure gradients associated with the coarse grid are then used to calculate upscaled permeabilities associated with the coarse-scale grid.

Abstract: The present invention provides a down hole spectrometer for determination of dew point pressure to determine an associated optimal pumping rate during sampling to avoid precipitation of asphaltenes in a formation sample. A sample is captured at formation pressure in a controlled volume. The pressure in the controlled volume is reduced. Initially the formation fluid sample appears dark and allows less light energy to pass through a sample under test. The sample under test, however, becomes lighter and allows more light energy to pass through the sample as the pressure is reduced and the formation fluid sample becomes thinner or less dense under the reduced pressure. At the dew point pressure, however, the sample begins to darken and allows less light energy to pass through it as apshaltenes begin to precipitate out of the sample. Thus, the dew point is that pressure at which peak light energy passes through the sample.

Abstract: A multi-scale finite-volume (MSFV) method to solve elliptic problems with a plurality of spatial scales arising from single or multi-phase flows in porous media is provided. Two sets of locally computed basis functions are employed. A first set of basis functions captures the small-scale heterogeneity of the underlying permeability field, and it is computed to construct the effective coarse-scale transmissibilities. A second set of basis functions is required to construct a conservative fine-scale velocity field. The method efficiently captures the effects of small scales on a coarse grid, is conservative, and treats tensor permeabilities correctly. The underlying idea is to construct transmissibilities that capture the local properties of a differential operator. This leads to a multi-point discretization scheme for a finite-volume solution algorithm. Transmissibilities for the MSFV method are preferably constructed only once as a preprocessing step and can be computed locally.

Abstract: The present invention is intended to achieve measurement of electrode impedance that is not easily affected by fluid noise, and to accurately detect adhesion and discriminate the type of fluid.