DrillPyze package
Module contents
An accelerated drillstring dynamics simulator and estimator for a fully coupled axial-torsional drillstring with bit-rock interaction.
Submodules
DrillPyze.drillstring module
A class describing a bottom hole assembly (BHA) and a drillstring for a typical rotary deep drilling system.
The BHA description may be loaded from a file in either xls or csv format.
- class DrillPyze.drillstring.BHA(name, filename)
Bases:
objectA class describing a bottom hole assembly with the ability to discretize the string
DrillPyze.dynamics module
A module that contains the simulation class and associated functions to enable simulation of a coupled axial-torsional drillstring model with a choice of bit-rock interaction models.
The estimation class is used to estimate the bit-rock interaction model parameters.
- class DrillPyze.dynamics.Estimator(num_instances, wellbore, bha)
Bases:
objectA class to maintain and update an ensemble based estimation technique
- increment(time, TD_SETPOINT=0, TD_ACT=0)
Increment the simulations with a certain topdrive rpm and recorded top drive torque. The simulations simulate forward at the topdrive rpm and then update their estimation assuming the topdrive torque is measured at the end of the simulation increment.
The simulation pool is then sorted by smallest error and all simulations are cloned to be equal to the best simulation.
Parameters
- timefloat
Number of seconds to step the simulations forward
- TD_SETPOINTfloat
Top drive rpm setpoint. Default is 0
- TD_ACTfloat
Top drive actual torque. Default is 0
- class DrillPyze.dynamics.Simulation(name, wellbore, bha)
Bases:
objectA class to maintain simulation state and describe a coupled axial-torsional drillstring model with a choice of bit-rock interaction models
- clone_estimator(source)
For ensemble based estimation, clone self to match best estimator
Parameters
- sourceDrillPyze.Simulation
the best estimator
- initialize_estimator(array_size, intensity)
Initialize the estimator.
Parameters
- array_sizeint
Length to preallocate for estimation
- intensityfloat
Intensity of update
- initialize_simulation(bitdepth, simulation_length=100, update_period=30, bit_constant=2000, params=None)
Initialize the simulation with the bit at a certain bitdepth
Parameters
- bitdepthfloat
Current depth of the bit
- simulation_lengthint
Length (in seconds) of the simulation. Used to preallocate arrays. Default value is 100 seconds.
- paramsdict
A dictionary of optional parameters to set up the simulation Default value is None
- parstep()
Helper function for multiprocessing
- speedhelper(dt=0.1, TD_RPM_SP=None, WOB_SP=None, bit_constant=None)
Step the simulation forward by dt seconds. Computations are vectorized in x
Parameters
- dtint
Number of seconds to advance the simulation
- TD_RPM_SPfloat
A change in the top drive set point. Default is None, meaning no change in top drive set point
- WOB_SPfloat
Current WOB setpoint
- step(dt=0.1, TD_RPM_SP=None, WOB_SP=None, bit_constant=None)
Step the simulation forward by dt seconds. Computations are vectorized in x
Parameters
- dtint
Number of seconds to advance the simulation
- TD_RPM_SPfloat
A change in the top drive set point. Default is None, meaning no change in top drive set point
- WOB_SPfloat
Current WOB setpoint
- class DrillPyze.dynamics.Simulation(name, wellbore, bha)
Bases:
objectA class to maintain simulation state and describe a coupled axial-torsional drillstring model with a choice of bit-rock interaction models
- clone_estimator(source)
For ensemble based estimation, clone self to match best estimator
Parameters
- sourceDrillPyze.Simulation
the best estimator
- initialize_estimator(array_size, intensity)
Initialize the estimator.
Parameters
- array_sizeint
Length to preallocate for estimation
- intensityfloat
Intensity of update
- initialize_simulation(bitdepth, simulation_length=100, update_period=30, bit_constant=2000, params=None)
Initialize the simulation with the bit at a certain bitdepth
Parameters
- bitdepthfloat
Current depth of the bit
- simulation_lengthint
Length (in seconds) of the simulation. Used to preallocate arrays. Default value is 100 seconds.
- paramsdict
A dictionary of optional parameters to set up the simulation Default value is None
- parstep()
Helper function for multiprocessing
- speedhelper(dt=0.1, TD_RPM_SP=None, WOB_SP=None, bit_constant=None)
Step the simulation forward by dt seconds. Computations are vectorized in x
Parameters
- dtint
Number of seconds to advance the simulation
- TD_RPM_SPfloat
A change in the top drive set point. Default is None, meaning no change in top drive set point
- WOB_SPfloat
Current WOB setpoint
- step(dt=0.1, TD_RPM_SP=None, WOB_SP=None, bit_constant=None)
Step the simulation forward by dt seconds. Computations are vectorized in x
Parameters
- dtint
Number of seconds to advance the simulation
- TD_RPM_SPfloat
A change in the top drive set point. Default is None, meaning no change in top drive set point
- WOB_SPfloat
Current WOB setpoint
- class DrillPyze.dynamics.Estimator(num_instances, wellbore, bha)
Bases:
objectA class to maintain and update an ensemble based estimation technique
- increment(time, TD_SETPOINT=0, TD_ACT=0)
Increment the simulations with a certain topdrive rpm and recorded top drive torque. The simulations simulate forward at the topdrive rpm and then update their estimation assuming the topdrive torque is measured at the end of the simulation increment.
The simulation pool is then sorted by smallest error and all simulations are cloned to be equal to the best simulation.
Parameters
- timefloat
Number of seconds to step the simulations forward
- TD_SETPOINTfloat
Top drive rpm setpoint. Default is 0
- TD_ACTfloat
Top drive actual torque. Default is 0
DrillPyze.hydraulics module
Hydraulics module for DrillPyze.
This module contains functions for calculating the flow rate, fluid velocity, Reynolds number for a pipe and the frictional pressure for a pipe and an annulus.
- DrillPyze.hydraulics.fluid_velocity(Q, Do, Di=None)
Calculate the fluid velocity in a pipe or an annulus.
Parameters
- Qfloat
Flow rate in gpm
- Dofloat
Outer diameter of the pipe in inches
- Difloat
Inner diameter of the pipe in inches. If Di is None, then the function will calculate the fluid velocity for a pipe.
- DrillPyze.hydraulics.friction_factor(NRe)
Calculate the friction factor for a pipe or an annulus.
Parameters
- NRefloat
Reynolds number for the pipe
- DrillPyze.hydraulics.frictional_pressure_drop(rho, Q, mu, L, Do, Di=None)
Calculate the frictional pressure drop in a pipe or an annulus.
Parameters
- rhofloat
Fluid density in ppg
- Qfloat
Flow rate in gpm
- mufloat
Fluid viscosity in cp
- Lfloat
Length of the pipe in ft
- Dofloat
Outer diameter of the pipe in inches
- Difloat
Inner diameter of the pipe in inches. If Di is None, then the frictional pressure drop is calculated for a pipe.
- DrillPyze.hydraulics.reynolds_number(rho, v, mu, Do, Di=None)
Calculate the Reynolds number for a pipe or an annulus.
Parameters
- rhofloat
Fluid density in lbm/ft^3
- vfloat
Fluid velocity in ft/s
- mufloat
Fluid viscosity in cp
- Dofloat
Outer diameter of the pipe in inches
- Difloat
Inner diameter of the pipe in inches. If Di is None, then the function will calculate the Reynolds number for a pipe.
DrillPyze.statics module
This module contains functions for calculating static forces and torques along the drillstring.
- DrillPyze.statics.normal_forces(well, bha, WOB=0, TOB=0, mu=0.3)
Calculate the normal forces along the drillstring.
Reference: Johancsik, Friesen and Dawson. Torque and Drag in Directional Wells – Prediction and Measurement. Journal of Petroleum Technology. 1984
Parameters
- wellDrillPyze.well.well_bore
A well_bore object initialized with a well profile. The wellpath must already be interpolated.
- bhaDrillPyze.drillstring.BHA
A BHA object initialized with a drillstring configuration. The BHA must already be discretized.
- WOBfloat
axial force at the bit (weight on bit). Default value = 0
- TOBfloat
torque at the bit. Default value = 0
- mufloat
friction coefficient. Default value = 0.3
DrillPyze.util module
A module containing functions for plotting the results of the simulation and other useful functions.
- DrillPyze.util.plot(fig, axes, sim, bha, M)
Update the plot
Parameters
- figmatplotlib.pyplot.figure
Figure to plot in
axes : tuple of axes objects sim : DrillPyze.dynamics.simulation
Simulation object
- bhaDrillPyze.drillstring.BHA
BHA object
- Mnumpy.array
Array of static friction torques
- DrillPyze.util.plot_estimates(fig, axes, sim, bha, M, data)
Update the plot
Parameters
- figmatplotlib.pyplot.figure
Figure to plot in
- axestuple of axes objects
Axes to plot in
- simDrillPyze.dynamics.simulation
Simulation object
- bhaDrillPyze.drillstring.BHA
BHA object
- Mnumpy.array
Array of static friction torques
- DrillPyze.util.plot_estimates_multiple(fig, axes, sims, bha, M, data)
Update the plot
Parameters
- figmatplotlib.pyplot.figure
Figure to plot in
- axestuple of axes objects
Axes to plot in
- simDrillPyze.dynamics.simulation
Simulation object
- bhaDrillPyze.drillstring.BHA
BHA object
- Mnumpy.array
Array of static friction torques
- DrillPyze.util.plot_map(time, depths, rpm, torque)
DrillPyze.well module
A class for a wellbore, which includes a well path, a casing setting depth and a hole size.
The well_profile library is used to interpolate along a wellbore survey.
- class DrillPyze.well.wellbore(well_survey, casing_depth, hole_size)
Bases:
objectA class for a wellbore, which includes a well path, a casing depth and a dimension. This class uses the well_profile library to interpolate along a wellbore survey.
- get_interpolated(md)
Interpolated wellpath for the depths defined.
Parameters
- mdnumpy array
Array of interpolation points
- get_trajectory()
Return the well trajectory object