Class ProductionProfile

java.lang.Object
neqsim.process.util.fielddevelopment.ProductionProfile
All Implemented Interfaces:
Serializable
public class ProductionProfile extends Object implements Serializable
Models production decline curves and plateau rates for field development planning.

This class provides comprehensive production forecasting capabilities including:

  • Standard decline curve models (exponential, hyperbolic, harmonic)
  • Plateau rate handling with automatic transition to decline
  • Integration with facility bottleneck analysis
  • Cumulative production tracking
  • Economic limit enforcement

Decline Curve Theory

The class implements Arps decline curve equations:

  • Exponential (b=0): q(t) = q_i * exp(-D*t)
  • Hyperbolic (0<b<1): q(t) = q_i / (1 + b*D*t)^(1/b)
  • Harmonic (b=1): q(t) = q_i / (1 + D*t)
where:
  • q_i = initial production rate
  • D = nominal decline rate (typically per year)
  • b = hyperbolic exponent
  • t = time

Facility Constraint Integration

When a ProcessSystem is provided, the production forecast respects facility constraints by using ProductionOptimizer to determine the maximum sustainable rate at each time step. This enables realistic forecasts where:

  • Plateau rate is limited by the tightest facility bottleneck
  • Bottleneck equipment shifts as production declines
  • Facility utilization is tracked throughout field life

Example Usage

// Basic decline curve calculation
DeclineParameters params = new DeclineParameters(10000.0, // initial rate: 10,000 Sm3/day
    0.15, // decline rate: 15% per year
    DeclineType.EXPONENTIAL, "Sm3/day");

double rateAfter2Years = ProductionProfile.calculateRate(params, 2.0);

// Full forecast with facility constraints
ProductionProfile profile = new ProductionProfile(facilityProcess);
ProductionForecast forecast = profile.forecast(feedStream, params, 8000.0, // plateau rate
    3.0, // plateau duration (years)
    500.0, // economic limit
    20.0, // forecast horizon (years)
    30.0); // time step (days)

System.out.println("Total recovery: " + forecast.getTotalRecovery());
System.out.println(forecast.toMarkdownTable());
Version:
1.0
Author:
ESOL
See Also:

  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      Serialization version UID.
      See Also:

    • DAYS_PER_YEAR

      private static final double DAYS_PER_YEAR
      Days per year for time conversion.
      See Also:

    • facility

      private final ProcessSystem facility
      Process system representing the surface facility.

    • optimizer

      private transient ProductionOptimizer optimizer
      Production optimizer for bottleneck analysis.

  • Constructor Details

    • ProductionProfile

      public ProductionProfile()
      Creates a ProductionProfile without facility constraints.

      Use this constructor for simple decline curve calculations that don't need to consider facility bottlenecks.

    • ProductionProfile

      public ProductionProfile(ProcessSystem facility)
      Creates a ProductionProfile with facility constraint analysis.

      When a ProcessSystem is provided, the forecast will use ProductionOptimizer to determine the maximum sustainable rate considering all equipment capacities.

      Parameters:
      facility - process system representing the surface facility

  • Method Details

    • forecast

      public ProductionProfile.ProductionForecast forecast(StreamInterface feedStream, ProductionProfile.DeclineParameters decline, double plateauRate, double plateauDurationYears, double economicLimit, double forecastYears, double timeStepDays)
      Generates a production forecast with plateau and decline phases.

      The forecast proceeds as follows:

      1. During plateau phase, production is maintained at the minimum of:
        • Requested plateau rate
        • Maximum facility rate (if facility is provided)
        • Reservoir deliverability from decline curve
      2. Decline phase begins when reservoir deliverability falls below plateau
      3. Forecast continues until economic limit or end of horizon
      Parameters:
      feedStream - stream to adjust for facility analysis (can be null if no facility)
      decline - decline curve parameters
      plateauRate - desired plateau production rate
      plateauDurationYears - maximum duration of plateau phase
      economicLimit - minimum economic production rate
      forecastYears - total forecast horizon in years
      timeStepDays - time step for forecast points in days
      Returns:
      complete production forecast

    • calculateRate

      public static double calculateRate(ProductionProfile.DeclineParameters params, double time)
      Calculates production rate at a given time using decline curve equations.

      This is a static utility method that can be used without instantiating the class. Time should be in the same units as the decline rate.

      Parameters:
      params - decline curve parameters
      time - time from start of decline
      Returns:
      production rate at specified time

    • calculateCumulativeProduction

      public static double calculateCumulativeProduction(ProductionProfile.DeclineParameters params, double time)
      Calculates cumulative production over a time period using analytical integration.

      Uses closed-form solutions for each decline type:

      • Exponential: Np = (qi/D) * (1 - exp(-D*t))
      • Hyperbolic: Np = (qi/(D*(1-b))) * (1 - (1+b*D*t)^(1-1/b))
      • Harmonic: Np = (qi/D) * ln(1 + D*t)
      Parameters:
      params - decline curve parameters
      time - time from start of decline
      Returns:
      cumulative production up to specified time

    • fitDecline

      public ProductionProfile.DeclineParameters fitDecline(List<Double> times, List<Double> rates, ProductionProfile.DeclineType type, String rateUnit)
      Fits decline parameters from historical production data.

      Uses least-squares regression to determine the best-fit decline parameters for the specified decline type. For exponential decline, this uses linear regression on ln(q) vs t. For hyperbolic, it uses iterative optimization.

      Parameters:
      times - list of time points
      rates - list of corresponding production rates
      type - desired decline curve type
      rateUnit - rate unit string
      Returns:
      fitted decline parameters
      Throws:
      IllegalArgumentException - if data is insufficient or invalid

    • fitExponentialDecline

      private double[] fitExponentialDecline(List<Double> times, List<Double> rates)
      Fits exponential decline using linear regression on ln(q) vs t.

    • fitHyperbolicDecline

      private double[] fitHyperbolicDecline(List<Double> times, List<Double> rates)
      Fits hyperbolic decline using grid search over b values.

    • fitHyperbolicForB

      private double[] fitHyperbolicForB(List<Double> times, List<Double> rates, double b)
      Fits hyperbolic decline for a fixed b value.

    • fitHarmonicDecline

      private double[] fitHarmonicDecline(List<Double> times, List<Double> rates)
      Fits harmonic decline using linear regression on 1/q vs t.

    • getFacilityBottleneckName

      private String getFacilityBottleneckName()
      Gets the name of the current facility bottleneck.

    • getFacility

      public ProcessSystem getFacility()
      Gets the facility process system.
      Returns:
      facility process system, or null if not configured