2. Simulación de Reservorios
SIMULADOR VERSUS MODELO DE RESERVORIO
•
Un modelo es un conjunto de datos que describen un reservorio
•
•
•
Profundidad, dimensiones, porosidad, espesor, permeabilidad
Densidad de fluidos, viscosidad, solubilidad gas, factores de volumen
Presión de reservorio, presión capilar, permeabilidades relativas
• Un simulador es un programa que calcula la distribución de
presión y saturación de un reservorio, como función de tiempo.
Seferino Yesquen
3. Simulación de Reservorios:
Introducción
Simulación de reservorios.- Uso de modelos matemáticos
para simular el comportamiento de un reservorio real
Simulador
INPUT
Ec. de continuidad ( E B M ).
Ec. de flujo de fluidos ( Darcy ).
Ec. de estado. ρ = f (p)
OUTPUT
Calidad de un estudio de simulación = f ( datos ingreso, modelo,
simulador )
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4. Discretización de Variables
Resolución de Ecuaciones de flujo ( EDP ) mediante diferencias finitas
Es necesario DISCRETIZAR las variables espacio y tiempo.
Discretización Espacio : División del reservorio en pequeñas distancias;
∆ x ∆ y ∆ z
∆ y
Sw
Sw
∆ x
Distancia
Distancia
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5. Discretización de Variables
Resolución de Ecuaciones de flujo ( EDP ) mediante diferencias finitas
Es necesario DISCRETIZAR las variables espacio y tiempo.
Discretización Tiempo : División. de historia de producción en intervalos de tiempo
Sw
Sw
∆ t
Tiempo
Tiempo
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7. Discretización de las ecuaciones de flujo
Primero la coordenada en X deberá ser dividido en un numero discreto de bloques.
Considerando un sistema poroso horizontal en una dimensión, se tiene un sistema
de N grid blocks, cada uno de longitud ∆x:
1
i-1
i
i+1
N
∆x
Esto es llamado un grid de block centrado, y las propiedades
promedios de reservorio se refieren al punto medio del bloque.
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8. Aproximación por Serie de Taylor
Aplicando las series de Taylor a las funciones de presión
podemos obtener una aproximación de las derivadas en
una ecuación de flujo lineal.
h
h2
h3
f ( x + h) = f ( x) + f ' ( x) +
f ' ' ( x) +
f ' ' ' ( x ) + ...
1!
2!
3!
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9. MODELADO
Método de Modelaje con diferencias finitas
Se resuelven las ecuaciones par cada celda (grid block) por métodos numéricos
para obtener los cambios de PRESION y SATURACION con el TIEMPO
La ecuación de Difusividad (1 Fase, flujo 1D)
La exactitud de los
datos de entrada
Impacta la exactitud
de los cálculos del
simulador
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10. Etapas de un Estudio Simulación
Comparar y Ajustar
1.Definición del Problema
y Objetivos
2.Caracterización De
Reservorios
3.Selección del Modelo
4.Construcción del Modelo
Modelado Geológico
Caracterización de fluidos
Scale up
Procesos
Funcionalidad
Dimensionamiento
GRID, grillado
Capas, layering
Propiedades de celdas
5.VALIDACION
MODELO
Resultados
Conclusiones
LECCIONES APRENDIDAS
Inicialización
Equilibrar sistema
AJUSTE HISTORIA
Calibrar
Evaluar
6.Predicciones
DOCUMENTACION
Diseñar planes
Sensibilidades
Análisis Económicos
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11. PRE Planning estudio de Simulación
Consideraciones
1. Objetivos del estudio
2. Valoración de las incertidumbres
3. Requerimientos y disponibilidad de datos
4. Metodología de modelado
5. Limitaciones de los procedimientos propuestos
6. Recursos:
7. Presupuesto del Proyecto
8. Tiempo disponible
9. Hardware, software
10.GENTE !!!
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12. Incertidumbre de estudio de Simulación
Fuentes de Incertidumbre en Simulación
Cantidad y Calidad
de Datos
Matemáticas del
Simulador
Geología
Escalamiento
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13. Incertidumbre de estudio de Simulación
Fuentes de Incertidumbre en Simulación
• Los resultados deberán estar
asociados a una “banda de
incertidumbre”
• Algunas veces se les pide a los
modelos, pronósticos que van mas
allá de la exactitud de los datos de
campo
• Esto se puede agravar por la falta de
buen juicio y control de ingeniería y
geología.
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14. Etapa 1: Definir Objetivos y Prioridades
CLARIDAD DEL PROPOSITO
Ejemplos de Metas de Estudios en Campos Nuevos
• Definir limites internos y externos del reservorio.
• Definir net pay, volumen & reservas
• Determinar numero optimo de locaciones y configuración de
pozos
• Optimizar el timing y tamaño de las facilidades de producción
• Estimar el potencial de recuperación.
• Anticipar la producción futura de fluidos y cambio operacionales.
• Determinar los caudales críticos para conning de agua gas.
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15. Etapa 1: Definir Objetivos y Prioridades
Ejemplos de Metas de Estudios en Campos Maduros
Monitorear el movimiento de los contactos de fluidos
Evaluar y seguir la productividad de los pozos
Evaluar el comportamiento histórico. Determinar tendencias y
anomalías.
Determinar la fuente de la producción de agua y gas. Identificar
pozos potenciales para workover.
Monitorear barrido del reservorio. Localizar petróleo by paseado.
Perforación infill
Estimar beneficios de procesos de recuperación secundaria y EOR:
Determinar conectividad entre reservorios múltiples.
Cuantificar migración a través de los limites del contrato.
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16. Etapa 2: Caracterización del reservorio
Transformación de Datos
Datos
Sísmica
Datos
Registros
Datos
Cores
Datos
Presión & Q
Datos
Fluidos
Datos
Roca-Fluido
INTERPRETACION
Descripción
Geológica
Caracterización
Fluidos
Modelo
Petro físico
Caracterización
Reservorios
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17. Etapa 2: Caracterización del reservorio
Caracterización Geológica
• La descripción Geológica
deberá identificar los
factores claves que
afectan el flujo de fluidos
en el reservorio.
• Que rol cumplen las
fallas, pinch-out, cambio
de facies, fracturas.
Seferino Yesquen
18. Etapa 2: Caracterización del reservorio
Caracterización de los fluidos
La caracterización de los fluidos define
las propiedades físicas de las mezclas de
los fluidos en el reservorio y como
pueden variar con cambios de P, T y V.
• Clasificar el tipo de fluido
• Determinar las propiedades de los
fluidos.
• Describir los mecanismos de
producción del reservorio.
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19. Etapa 2: Caracterización del reservorio
Modelo Petrofisico
El modelo Petro físico define donde están
localizados los volúmenes de petróleo,
gas y agua, así como es el
comportamiento de estos fluidos en la
presencia de diferentes tipos de rocas.
• Mojabilidad de la roca
• Presión Capilar
• Permeabilidades relativas
• End points, Swc, Sor
• Contactos de fluidos
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20. SELECCIÓN DEL MODELO
Aspectos del Modelo
1. Proceso
2. Funcionalidad
3. Alcance
4. Dimensionalidad
5. Metodología
Petroleo Negro
Determinar
Determinar
Condensado
Proceso
Proceso
Miscible
Composicional
Termal
Energía
Determinar
Determinar
Funcionalidad
Seguimiento Funcionalidad
frentes
Determinar
Determinar
Porción
Alcance
Alcance
del campo
0-D
1-D
Real
Determinar
Determinar
Dimensionalidad
Dimensionalidad
Energía &
Seguimiento frentes
Todo
el campo
2-D
3-D
Determinar
Determinar
Metodología
Metodología
Conceptual
Determinar
Determinar
Grid y factibilidad
Grid y factibilidad
Especificaciones Finales del Modelo
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21. SELECCIÓN DEL MODELO
Determine el Proceso
1. Petróleo Negro
2. Condensado
3. Miscible
4. Composicional
5. Térmico
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22. SELECCIÓN DEL MODELO
Determine La Dimensionalidad
1. Use modelos 1D para flujos
lineales o radiales en una
dirección.
2. Use modelos 2D para flujos en
dos direcciones: Cross sections
3. Modelos 3D para flujo en tres
direcciones: Comportamiento de
arreglos, segmentos o campo
entero.
Seferino Yesquen
23. SELECCIÓN DEL MODELO
Determine La Metodología
Modelo Conceptual
Modelo Real
Propiedades de mayor incertidumbre
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24. CONSTRUCCION DEL MODELO
Convirtiendo el Modelo de la Tierra en un
Modelo de Simulación.
1. Control de Calidad de errores y
problemas del modelo geológico.
2. Scalar el modelo
3. Hacer un Output del modelo en
formato del simulador
4. Hacer un output de la información
de las fallas en el simulador.
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25. VALIDACION DEL MODELO
1
Desarrolle un plan de validación
2
Inicializar el modelo de simulación
3
Equilibrar el modelo
4
AJUSTAR LA HISTORIA
5
Calibrar el Modelo
6
Evaluar resultados
Seferino Yesquen
26. Datos Requeridos
L
K
A
T=KA/L
• A fin de realizar balance de materia en cada grid
block, el simulador necesita saber:
La presión y saturación inicial de cada grid block
La transmisibilidad para el flujo en las direcciones X, Y Z
La producción o inyección de cada grid block
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27. Volumen de Roca
Volumen de roca y
profundidad de los puntos
medios
DX
Dx
Dy
DY
Dz
DZ
• Se define la profundidad y dimensiones de cada celda
• El volumen total o de roca puede ser calculado
Volumen de roca = DX*DY*DZ
• El punto medio de la celda puede ser calculado
Punto medio = Prof. Tope + DZ/2
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28. Volumen Poral
VOLUMEN PORAL
DX
Dx
Dy
DY
Dz
DZ
• Valores de porosidad, relacion Net-to-gross y espesor neto
son asignados a cada celda de los mapas.
• EL volumen poral es calculado :
VOLUMEN PORAL: DX*DY*DZ*NTG*PORO
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29. Permeabilidad
L
PERMEABILIDAD
K
A
T=KA/L
• La permeabilidad para cada celda es especificada ya sea de
mapas o de correlaciones
• La transmisibilidad para cada cara de flujo puede ser calculada.
Transmisibilidad = K A / L
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30. Parámetros de Equilibración
Cell Mid-Point
Pi
h
Datum
OWC
• El nivel de referencia, presión a este nivel, y los contactos de fluidos
son especificados
• De estos datos, la presión de petróleo, agua y gas son tabuladas como
función de la profundidad.
• Estas tablas usan las gradientes de los fluidos tomadas de los datos
PVT
• Las presiones de cada celda son calculadas de la tabla para el punto
medio de cada celda
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31. Saturaciones Iniciales: So, Sw, Sg
Fuera de la zona de transicion
Gas
Gas Oil Transition Zone
Oil
Water Oil Transition Zone
• Para celdas que no caen dentro de la zona de transición, las saturación
inicial de agua y gas son determinadas de los endpoints de las curvas de
permeabilidades relativas.
• La saturación de petróleo es siempre determinada de 1-Sw-Sg
Seferino Yesquen
32. Saturaciones Iniciales, So, Sw, Sg
En la zona de transición
Cell Mid-Point
h
Oil Water Contact
• En las zonas de transición, los valores iniciales de Sw y Sg son
determinados de una tabla de presión capilar versus Sw ó Sg.
• Las presiones capilares son calculadas como la diferencia entre
las presiones de las fases.
Pcow = Pw - Po =
h
Pcog = Pg - Po =
h
Seferino Yesquen
35. VALIDACION DEL MODELO
Para VALIDAR adecuadamente el Modelo de Reservorios
debemos mantener en la mente siempre :
• El ajuste de Historia no deberá nunca ser logrado a expensas
de modificar parámetros que son físicamente y/o
geológicamente errados.
• Aun cuando un modelo este completamente validado los
resultados de la simulación tendrán todavía algún grado de
incertidumbre.
Seferino Yesquen
36. Que es ajuste de Historia?
Watercut
historical
model
Oil rate
historical
model
Barrels
Cumulative oil
Watercut
Barrels per day
• Proceso por el cual un modelo de simulación de
reservorios es alterado de alguna forma para igualar la
historia conocida de producción
Seferino Yesquen
37. Por que ajustar la Historia ?
Generalmente se asume que si un modelo de simulación
es ajustado , entonces podrá predecir mas exactamente el
comportamiento futuro y representara adecuadamente
los cambios de saturación y presión.
Barrow Island Field -- Windalia Sand
Predictive cases, for different total field injection rates
20,000
18,000
16,000
12,000
10,000
8,000
6,000
5000 BOPD economic limit
4,000
2,000
History BOPD
Oil rate -- for 100M BWIPD
Oil rate -- for 200M BWIPD
Dec-25
Dec-23
Dec-21
Dec-19
Dec-17
Dec-15
Dec-13
Dec-11
Dec-09
Dec-07
Dec-05
Dec-03
Dec-01
Dec-99
Dec-97
0
Dec-95
Barrels oil per day
14,000
Oil rate -- base case
Oil rate -- for 150M BWIPD
Oil rate -- 200M BWID, delay until 2007
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38. Que ajustamos en el proceso de Ajuste de Historia?
Datos de producción
Petróleo , agua y gas
componentes de los fluidos
Segregación de producción
Datos de presión
RFT, SFT, BHP, THP
monitoreo continuo
Otros datos
Distribución de saturación (pozos, de 4D ), …
Los datos son de por si inciertos y algunos registros
son inexactos.
Seferino Yesquen
39. Que parámetros son cambiados para
lograr un ajuste de historia?
•
•
•
•
•
•
•
Permeabilidad (distribución espacial)
Porosidad (volumen poral)
Distribución Inicial de fluidos
PVT, Kr´s, Pc, Cr,…
Fallas (transmisibilidad, ubicación)
Pozos (completaciones, IP’s, ubicaciones)
Otros ????
Algunas variables criticas frecuentemente no son
conocidas a priori
Seferino Yesquen
40. Ajuste de Historia - Importancia
• Parte final de la historia … Mayor atención !!!
Seferino Yesquen
41. PREDICCIONES
Hacer PREDICCIONES
Consideraciones Importantes para hacer predicciones
• Los casos de predicciones nunca deben exceder las capacidades
del modelo de simulación.
• Las predicciones necesitan ser consistentes con las practicas de
campo.
• Cas siempre la simulación trae consigo una solución no única con
incertidumbres inherentes de:
•Falta de validación. Ej Reservorios con datos escasos de
geología e ingeniería.
•Incertidumbres inherentes a la caracterización de reservorios
y / o escalamiento a las dimensiones del modelo.
Seferino Yesquen
42. PREDICCIONES – Agregando Valor
Imaginarse el FUTURO !!
Casos
Reservas
Inversión
VAN
Caso Base
RB
-
VANB
Caso 1:
Base + WO´s
R1
I1
VAN1
Caso 2:
Caso 1 + Perforación
R2
I2
VAN2
Caso 3:
Caso 2 + RS, EOR
R3
I3
VAN3
Seferino Yesquen
Notas del editor
Simulators and Models
Through the years, many engineers have referred to simulators and models as though they were the same, which is not true, and can cause confusion. A simulator is a program, generally written in fortran, that is typically leased from one of the major vendors, such as GEOQUEST RESERVOIR TECHNOLOGIES. A model is a set of data used to describe a reservoir, its fluids, wells, etc.
During this course we will be building a model using data provided by the instructor. ECLIPSE 100 is the simulator (or program) we will be using to do this work.
Matrices
In order to solve the mass balance equation for each grid cell, all cells have to be solved at the same time. The reason for this is that in order to determine the flow of fluids into and out of a cell, you need to know what is going on in the surrounding cells. In other words, there has to be consistency between cells. To solve several equations at the same time, it is convenient to use matrices.
Data Requirements
In order to perform a mass balance on each cell, the simulator needs to be able to determine the initial mass of oil, water and gas that exists in each grid block and also be able to determine how much fluid flows in or out of each block.
The initial mass of each fluid is determined from the dimensions, net thickness and porosity of each block, the initial saturation of each fluid within the block, and the fluid density. The fluid densities are determined from PVT data required for each fluid present in the reservoir. The initial saturations are determine from the depth of each block relative to the fluid contacts, relative permeability endpoints, and capillary pressure data.
The flow of fluids in a simulator can be described in general as:
q = T
Here you have a flow rate equal to a transmissibility*mobility*driving force.
The driving force in our case is the potential drop either between two cells or a cell and the well. The initial pressure of each block is determined from the initial pressure at datum, the depth of each block, and initial reservoir fluid gradients. The gradients are determined from the PVT data specified for each fluid initially present in the reservoir.
Bulk Volume and Midpoint Depth
The dimensions and top depth of each grid cell are required by the simulator. The Areal dimension of each cell is taken from the simulation grid. The vertical dimension of each cell is actually the gross thickness assigned from gross thickness maps. The top depth of each grid cell can be assigned from structure maps for each model layer, however, where applicable, most simulators will allow the user to specify the top depth of the reservoir for the first model layer and the simulator will determine the depth of each grid block from the top of the reservoir and gross thickness values.
From these data, the simulator is able to determine the bulk volume of each cell and the midpoint depth of each cell. The cell is actually represented vertically by this mid-cell depth to determine the initial pressure of the block and the angle and distance of flow from one cell to another. Therefore, if this value is incorrect, its effect with regard to these calculations needs to be considered.
Pore Volumes
The porosity and net thickness or net to gross are specified by the user for each grid cell. These values are taken from maps created for each model layer and are used to determine the initial pore volume and, subsequently, initial volumes of oil, water, and gas in each cell. As a result, the net thickness includes all sand that contains fluid expected to add pressure support, regardless of the type of fluid that initially exists in the sand.
It is actually the pore volume that is needed by the simulator. After the pore volume for each cell has been determined, the porosity becomes unimportant.
The net thickness or net to gross values will also be used to determine the net sand thickness used in flow calculations from one cell to another.
Permeability and Transmissibilities
A transmissibility must be calculated for each flow face in order to determine the flow of fluids between cells. By default, most simulators use what is referred to as a five point finite difference scheme. The five points refer to a cell and the four cells surrounding it, in the horizontal plane. In other words, there is no diagonal flow considered by the simulator. Some simulators have what is referred to as a nine point finite difference scheme which, in its most rigorous form, does consider diagonal flow in the horizontal plane. In a five point finite difference scheme, flow is allowed between a cell, the four cells surrounding it in the horizontal plane, and the cells above and below it. Therefore, transmissibilities are required for each of the six faces of flow, for each cell.
Similarly, a transmissibility for fluid flow between each cell and the well must be determined to calculate flow in and out of each well. These transmissibilities are calculated in general as:
Values for permeability are assigned either from maps or specified using a correlation. In most cases the permeability in the x and y direction are specified to be the same, though most simulators will allow directional permeabilities. The permeability in the vertical direction is usually specified as the horizontal permeability times some factor. These values are used together with the net thickness and perforated thickness to calculate transmissibilities.
There are a variety of transmissibility calculations. These are discussed in Chapter 6 along with different formats for specifying this data.
It is actually the transmissibility that is important for each flow face, for each cell. Once all transmissibilities are determined, the permeability becomes unimportant.
Equilibration Parameters
For most problems, the reservoir is initialized assuming that the reservoir is in equilibrium. Many problems can arise from poor initialization of pressures and saturations. It is therefore important that the initial pressures, saturations, and capillary pressures are consistent with each other.
Initial Pressures
The initial pressure for each grid cell is determined from the midpoint depth of the block, a datum depth, the initial pressure at datum, and the initial fluid gradients present in the reservoir. We have already seen how the midpoint depth of each block is determined. The initial pressure at datum is specified to the simulator along with the initial oil-water and gas-oil contacts. These parameters are generally referred to as Equilibration or Initialization parameters. The simulator uses this data to determine the initial pressure, for each phase, for each cell.
In ECLIPSE, tables of oil pressure, water pressure, and gas pressure are created as a function of depth. The range of depths is determined from the midpoint depths of each cell and the fluid contacts specified by the user. The pressure at each depth is calculated using the pressure at datum and the appropriate fluid gradients determined from the PVT data. The initial pressure for each cell is then determined from a table look-up process
Initial Oil, Water, and Gas Saturations
The initial oil, water, and gas saturations are used to determine the initial volume of fluids in each cell. To rigorously determine these volumes we need to recognize that part of a cell may be in the transition zone and the cell may be cut by a fluid contact.
For those volumes of the cell that do not lie in the transition zone, the initial water and gas saturation are determined from the relative permeability endpoints. This is usually true for all simulators. The lowest water saturation value found in the table is usually assigned to those volumes above the oil-water contact. For volumes below the oil-water contact, in some simulators, the value of water saturation is automatically set to a value of 1.0, however, in ECLIPSE, the value is set to the highest water saturation found in the relative permeability table. Similarly for gas, the values of gas saturation for any volume below the gas-oil contact is set to the lowest value found in the relative permeability table. This value is usually 0.0. The value of gas saturation above the gas-oil contact is set to the highest values found in the table, usually 1-Swc. For those volumes of a cell that are in a transition zone, the saturation is determined from the capillary pressure table. The resulting water and gas saturations are then a pore volume average of the volumes in the transition zone and outside the transition zone. The oil saturation is always calculated as 1-Sw-Sg.
Initialization Runs
It is important for the user to check the initial volumes of oil, water, and gas calculated by the simulator. This is a first step, basic check of the reservoir data. In particular, the initial oil volume should be checked and compared to other estimates of the initial oil in place.
Capillary Pressures
In the simulator, capillary pressures are determined for each grid cell from the phase pressures. The oil-water capillary pressure is calculated as a difference between the oil and water phase pressures. Similarly, the gas-oil capillary pressure is a difference between the oil and gas phase pressures.
Capillary pressures are used to determine the initial fluid saturations for each cell, in the transition zone. A table of water saturation versus capillary pressure is specified by the user, to the simulator. The simulator knows the capillary pressure for each cell and simply determines the water saturation from the table.
Capillary pressure measurements taken in the laboratory are usually not used to specify the initial water saturation distribution in the reservoir. Instead, initial values of water saturation are derived from logs and specified to the simulator. This data is referred to as Pseudo Capillary Pressure data.
Permeability and Transmissibilities
A transmissibility must be calculated for each flow face in order to determine the flow of fluids between cells. By default, most simulators use what is referred to as a five point finite difference scheme. The five points refer to a cell and the four cells surrounding it, in the horizontal plane. In other words, there is no diagonal flow considered by the simulator. Some simulators have what is referred to as a nine point finite difference scheme which, in its most rigorous form, does consider diagonal flow in the horizontal plane. In a five point finite difference scheme, flow is allowed between a cell, the four cells surrounding it in the horizontal plane, and the cells above and below it. Therefore, transmissibilities are required for each of the six faces of flow, for each cell.
Similarly, a transmissibility for fluid flow between each cell and the well must be determined to calculate flow in and out of each well. These transmissibilities are calculated in general as:
Values for permeability are assigned either from maps or specified using a correlation. In most cases the permeability in the x and y direction are specified to be the same, though most simulators will allow directional permeabilities. The permeability in the vertical direction is usually specified as the horizontal permeability times some factor. These values are used together with the net thickness and perforated thickness to calculate transmissibilities.
There are a variety of transmissibility calculations. These are discussed in Chapter 6 along with different formats for specifying this data.
It is actually the transmissibility that is important for each flow face, for each cell. Once all transmissibilities are determined, the permeability becomes unimportant.
Permeability and Transmissibilities
A transmissibility must be calculated for each flow face in order to determine the flow of fluids between cells. By default, most simulators use what is referred to as a five point finite difference scheme. The five points refer to a cell and the four cells surrounding it, in the horizontal plane. In other words, there is no diagonal flow considered by the simulator. Some simulators have what is referred to as a nine point finite difference scheme which, in its most rigorous form, does consider diagonal flow in the horizontal plane. In a five point finite difference scheme, flow is allowed between a cell, the four cells surrounding it in the horizontal plane, and the cells above and below it. Therefore, transmissibilities are required for each of the six faces of flow, for each cell.
Similarly, a transmissibility for fluid flow between each cell and the well must be determined to calculate flow in and out of each well. These transmissibilities are calculated in general as:
Values for permeability are assigned either from maps or specified using a correlation. In most cases the permeability in the x and y direction are specified to be the same, though most simulators will allow directional permeabilities. The permeability in the vertical direction is usually specified as the horizontal permeability times some factor. These values are used together with the net thickness and perforated thickness to calculate transmissibilities.
There are a variety of transmissibility calculations. These are discussed in Chapter 6 along with different formats for specifying this data.
It is actually the transmissibility that is important for each flow face, for each cell. Once all transmissibilities are determined, the permeability becomes unimportant.
Simulators and Models
Through the years, many engineers have referred to simulators and models as though they were the same, which is not true, and can cause confusion. A simulator is a program, generally written in fortran, that is typically leased from one of the major vendors, such as GEOQUEST RESERVOIR TECHNOLOGIES. A model is a set of data used to describe a reservoir, its fluids, wells, etc.
During this course we will be building a model using data provided by the instructor. ECLIPSE 100 is the simulator (or program) we will be using to do this work.