API Reference

Material

Material(name, rho[, E, G_s, Poisson, ...])

Material used on shaft and disks.

Elements

ShaftElement(L, idl, odl[, idr, odr, ...])	A shaft element with 12 degrees of freedom.
DiskElement(n, m, Id, Ip[, tag, ...])	A disk element.
BearingElement(n, kxx, cxx[, mxx, kyy, kxy, ...])	A bearing element.
SealElement(n, kxx, cxx[, mxx, kyy, kxy, ...])	A seal element.
BallBearingElement(n, n_balls, d_balls, fs, ...)	A bearing element for ball bearings.
RollerBearingElement(n, n_rollers, ...[, ...])	A bearing element for roller bearings.
CylindricalBearing(n[, speed, weight, ...])	Cylindrical hydrodynamic bearing - Simplified analytical model.
FluidFilmBearing(n[, speed, frequency, ...])	Journal bearing solved by the fluid-film TEHD engine.
FixedGeometryBearing(n, **kwargs)	Fixed-geometry journal bearing described by per-pad arrays.
PlainJournal(n[, pad_axial_length, ...])	Plain (axial-groove) cylindrical journal bearing.
PartialArcBearing(n[, pad_arc, arc_center, ...])	Partial-arc journal bearing: a single fixed pad.
EllipticalBearing(n[, pad_arc, preload])	Elliptical (lemon-bore) journal bearing: two preloaded lobes.
OffsetHalvesBearing(n[, pad_arc, preload, ...])	Offset-halves journal bearing: two halves displaced at the split.
MultiLobeBearing(n[, n_lobes, pad_arc, ...])	Multi-lobe journal bearing: n_lobes preloaded arcs.
PressureDamBearing(n[, pad_arc, dam_arc, ...])	Pressure-dam journal bearing: a stepped pocket in selected pads.
TiltingPad(n[, journal_diameter, preload, ...])	Tilting-pad journal bearing.
ThrustPad(n, pad_inner_radius, ...[, ...])	Thermo-Hydro-Dynamic (THD) Tilting Pad Thrust Bearing.
SqueezeFilmDamper(n, frequency, ...[, ...])	Squeeze Film Damper (SFD) element in ROSS standard format.
LabyrinthSeal(n, shaft_diameter, ...[, ...])	Labyrinth seal - Compressible flow model with rotordynamic coefficients.
HolePatternSeal(n, shaft_diameter, ...[, ...])	Hole-pattern annular seal - Bulk flow model with dynamic coefficients.
HybridSeal(n, shaft_diameter, ...[, ...])	Hybrid seal - Compressible flow model with rotordynamic coefficients.
MagneticBearingElement(n, g0, i0, ag, nw[, ...])	Magnetic Bearing Element.
GearElement(n, m, Id, Ip, n_teeth[, ...])	A gear element.
GearElementTVMS(n, material, width, ...[, ...])	A gear element with Time-Varying Mesh Stiffness (TVMS) modeling.
Mesh(driving_gear, driven_gear[, ...])	A class representing the meshing behavior between two gears in contact, including stiffness and contact ratio calculations.
CouplingElement(m_l, m_r, Ip_l, Ip_r[, ...])	A coupling element.
Probe(node[, angle, direction, tag])	Class of a probe.
PointMass([n, m, mx, my, mz, tag, ...])	A point mass element.
MotorElement(n, power_rated, voltage_rated, ...)	Create a 3-phase induction motor element for rotordynamic analysis.

Rotor and Analysis

Rotor class and available methods for analysis (run_* methods).

Rotor(shaft_elements[, disk_elements, ...])	A rotor object.
MultiRotor(driving_rotor, driven_rotor, ...)	A class representing a multi-rotor system.
Rotor.run_modal
Rotor.run_critical_speed([speed_range, ...])	Calculate the critical speeds and damping ratios for the rotor model.
Rotor.run_freq_response([speed_range, ...])	Frequency response for a mdof system.
Rotor.run_forced_response([force, ...])	Forced response for a mdof system.
Rotor.run_unbalance_response(node, ...[, ...])	Unbalanced response for a mdof system.
Rotor.run_campbell(speed_range[, ...])	Calculate the Campbell diagram.
Rotor.run_time_response(speed, F, t[, method])	Calculate the time response.
Rotor.run_level1([n, stiffness_range, num])	Plot level 1 stability analysis.
Rotor.run_ucs([stiffness_range, ...])	Run Undamped Critical Speeds analyzes.
Rotor.run_static()	Run static analysis.
Rotor.run_misalignment(node, ...[, coupling])	Run analysis for the rotor system with misalignment given an unbalance force.
Rotor.run_rubbing(n, distance, ...[, torque])	Run analysis for the rotor system with rubbing given an unbalance force.
Rotor.run_crack(n, depth_ratio, node, ...[, ...])	Run analysis for the rotor system with crack given an unbalance force.
Rotor.run_harmonic_balance_response(speed, ...)	Compute the steady-state response of the rotor using the Harmonic Balance method.
Rotor.run_amb_sensitivity(speed, t_max, dt)	Run Active Magnetic Bearing (AMB) sensitivity analysis.
Rotor.run_amb_non_collocation(magnetic_bearing)	Run a modal sensor-actuator non-collocation analysis.
Rotor.run_clearance_analysis(speed_range, ...)	Close-clearance check of the unbalance response after API 617.
Rotor.run_mesh_convergence([rtol, ...])	Find a shaft discretization with converged natural frequencies.
Rotor.run_with_motor(t, node, ...[, ...])	Run time response with electric motor torque at the motor node.
Rotor.refine(subdivisions)	Split the shaft intervals of the rotor in equal shaft elements.
Rotor.refine_mesh([max_ld, min_ld, parts])	Subdivide the shaft elements by their length-to-diameter ratio.
Rotor.api617_unbalance(mode, ...[, num_modes])	Unbalance amount and placement for a mode as defined by API 617.

Example Rotors

Ready-to-use rotor models for tutorials, doctests, and quick experimentation.

rotor_example()	Create a rotor as example.
compressor_example()	Create a compressor as example.
rotor_example_6dof()	Create a rotor as example.
rotor_example_with_damping()	Create a rotor as example.
rotor_example_amb_simple()
rotor_example_amb_complex_controllers([ambs])	Create a rotor example with complex magnetic bearing controllers.
rotor_example_amb_general_controllers([...])	This function creates the model of a test rig rotor supported by magnetic bearings.
motor_example()	Create an example of motor element.

Results

These are classes used to store results and to provide useful methods such as plotting.

Orbit(*, node, node_pos, ru_e, rv_e)	Class used to construct orbits for a node in a mode or deflected shape.
Shape(vector, nodes, nodes_pos, ...[, normalize])	Class used to construct a mode or a deflected shape from a eigen or response vector.
CriticalSpeedResults(_wn, _wd, log_dec, ...)	Class used to store results from run_critical_speed() method.
ModalResults(speed, evalues, evectors, wn, ...)	Class used to store results and provide plots for Modal Analysis.
CampbellResults(speed_range, wd, log_dec, ...)	Class used to store results and provide plots for Campbell Diagram.
FrequencyResponseResults(freq_resp, ...)	Class used to store results and provide plots for Frequency Response.
ForcedResponseResults(rotor, forced_resp, ...)	Class used to store results and provide plots for Forced Response analysis.
StaticResults(deformation, Vx, Bm, w_shaft, ...)	Class used to store results and provide plots for Static Analysis.
SummaryResults(df_shaft, df_disks, ...)	Class used to store results and provide plots rotor summary.
MeshConvergenceResults(rotor, subdivisions, ...)	Store and plot the results of a mesh convergence analysis.
TimeResponseResults(rotor, t, yout, xout[, ...])	Class used to store results and provide plots for Time Response Analysis.
Level1Results(stiffness_range, log_dec)	Class used to store results and provide plots for Level 1 Stability Analysis.
UCSResults(stiffness_range, stiffness_log, ...)	Class used to store results and provide plots for UCS Analysis.
HarmonicBalanceResults(rotor, speed, t, Qt, ...)	Class used to store results and provide plots for Harmonic Balance Analysis.
SensitivityResults(sensitivity_data, ...)	Results from the sensitivity analysis for the rotor AMBs.
AmbNonCollocationResults(speed, ...[, ...])	Results from a lateral AMB sensor-actuator non-collocation analysis.
ClearanceResults(speed_range, ...[, ...])	Results of the API 617 close-clearance check.
MotorResponseResults(t, electric_torque, ...)	Store and plot motor time response results.
PhaseResults(t, data, data_type[, t_eval])	Store and plot phase data.

Bearing Results

Post-processing classes for thermo-hydro-dynamic bearing models.

BearingResults(frequency, pressure_fields, ...)	Abstract base class for fluid film bearing post-processing results.
FluidFilmBearingResults(frequency, ...[, ...])	Post-processing results for FluidFilmBearing.
ThrustPadResults(frequency, pressure_fields, ...)	Post-processing results for a ThrustPad bearing.
SqueezeFilmDamperResults(frequency, kxx, ...)	Post-processing results for a SqueezeFilmDamper bearing.

Faults

Fault models for misalignment, rubbing, and crack analyses.

MisalignmentFlex(rotor, n, mis_type, ...[, ...])	Model misalignment on a given flexible coupling element of a rotor system.
MisalignmentRigid(rotor, n, mis_distance[, ...])	Model misalignment on a given rigid coupling element of a rotor system.
Rubbing(rotor, n, distance, ...[, torque])	Model rubbing based on Finite Element Method on a given shaft element of a rotor system.
Crack(rotor, n, depth_ratio[, crack_model, ...])	Model a crack on a given shaft element of a rotor system.

Model Reduction

Methods for reducing the size of rotor finite element models.

ModelReduction([method])
PseudoModal([method])	Pseudo-modal method.
Guyan([method])	Guyan reduction method.

Motor Drives

Electrical sources that feed a MotorElement.

SourceAC(voltage_net, frequency_net[, ...])	Create an ideal 3-phase AC source with harmonics and voltage unbalance support.
InverterVF(voltage_dc, frequency_s, ...[, ...])	Simulate a three-phase voltage source inverter with V/f adjustment technique.
InverterFOC(voltage_dc, frequency_s, ...[, ...])	Simulate a three-phase voltage source inverter with indirect Field-Oriented Control.

Stochastic Analysis

Stochastic elements, rotor assembly, and results for uncertainty quantification.

ST_Material(name, rho[, E, G_s, Poisson, color])	Create instance of Material with random parameters.
ST_ShaftElement(L, idl, odl[, idr, odr, ...])	Random shaft element.
ST_DiskElement(n, m, Id, Ip[, tag, color, ...])	Random disk element.
ST_BearingElement(n, kxx, cxx[, mxx, kyy, ...])	Random bearing element.
ST_PointMass(n[, m, mx, my, tag, color, ...])	Random point mass element.
ST_Rotor(shaft_elements[, disk_elements, ...])	A random rotor object.
ST_CampbellResults(speed_range, wd, log_dec, ...)	Store stochastic results and provide plots for Campbell Diagram.
ST_FrequencyResponseResults(speed_range, ...)	Store stochastic results and provide plots for Frequency Response.
ST_ForcedResponseResults(forced_resp, ...)	Store stochastic results and provide plots for Forced Response.
ST_TimeResponseResults(t, yout, xout, ...)	Store stochastic results and provide plots for Time Response and Orbit Response.

Utilities

Unit conversion helpers, visualization utilities and speed ranges for sweep analyses.

Q_	alias of Quantity
get_data_from_figure(fig)	Get data from a Plotly scatter plot (XY) and convert to a pd.DataFrame.
visualize_matrix(rotor, matrix[, frequency])	Visualize global matrix.
lubricants_dict

speed_range_from_endpoints(speed_start, ...)

Make an evenly spaced speed range from its end points.