Summary for: MaterialBase < Indexable

Class summary

MaterialBase Base class for materials.

Not really used right now, see Material.

Properties

.B - given B-curve (T)

.H - given H-curve (A/m)

.Poissons_ratio Poisson’s ratio.

Fetched from this.material_properties.Poissons_ratio.

.Youngs_modulus Young’s modulus in SI units.

Fetched from this.material_properties.Youngs_modulus

.density Density in SI units.

Fetched from this.material_properties.rho

.domains - list of domains that are made of this material

.electrical conductivity in SI units.

Fetched from this.material_properties.sigma

At 20 C by default.

.elements - indices to finite elements

.intrinsic_coercivity Intrinsic coercivity.

The intrinsic coercivity, often (a bit naiively) used as a demagnetization limit. (A/m). Fetched from this.material_properties.HcJ

At 20C by default.

.intrinsic_coercivity_temperature_coefficient Temperature

coefficient for intrinsic coercivity.

Fetched from this.material_properties.intrinsic_coercivity_temperature_coefficient

.iron_loss_computation_method Iron loss computation method.

This property allows an option to toggle the iron loss computation method. Indeed, the loss_density method of the Material class calls the method with its name equal to this property.

However, subclasses may have a different loss_density method.

.is_symmetric - Is the differential reluctivity symmetric?

.MaterialBase/material_properties is a property.

.plot_args - plotting instructions for this

.relative_permeability Relative permeability.

Only used for PMs by default. Fetched from this.material_properties.mur.

.remanence_flux_density Remanence flux density in T.

Fetched from this.material_properties.Br

At 20C by default.

.remanence_temperature_coefficient Remanence flux density temp.

coeff. in 1/C.

Fetched from this.material_properties.alpha_Br

.specific_heat_capacity Specific heat capacity in SI units.

Fetched from this.material_properties.specific_heat_capacity

.stacking_factors - list of stacking factors per each element

.temperature_coefficient_of_resistivity Resistivity temp. coeff. in

SI units.

Fetched from this.material_properties.alpha_sigma

.thermal_conductivity Thermal conductivity in SI units.

Fetched from this.material_properties.thermal_conductivity

Methods

Class methods are listed below. Inherited methods are not included.

.MaterialBase Base class for materials.

Not really used right now, see Material. Documentation for MaterialBase/MaterialBase doc MaterialBase

.MaterialBase/clear_copy is a function.

obj = MaterialBase

.default copy for most properties

.MaterialBase/detach is a function.

obj = MaterialBase

.MaterialBase/differential_reluctivity is a function.

obj = MaterialBase

.electrical_conductivity_at_temperature Electrical conductivity

at given temperature.

sigma = electrical_conductivity_at_temperature(this, T) returns the electrical conductivity sigma (S/m) at the given temperature T (C)

.elementwise_density Elementwise density.

Returns a scalar by default; can be subclassed to support varying properties.

.elementwise_plane_stress_stiffness_tensor Plane-stress stiffness tensor.

Returns the elementwise stiffness tensor, for plane-stress formulation, using Voigt notation in column-major format.

Returns a single tensor by default, implying constant property across all elements.

.elementwise_stiffness_tensor Plane-strain stiffness tensor.

Returns the elementwise stiffness tensor, for plane-strain formulation, using Voigt notation in column-major format.

Returns a single tensor by default, implying constant property across all elements.

.get_B_data Compute flux density waveforms and other data.

Bdata = get_B_data(solution, args)

Bdata is an array of structs with the fields (one struct per quadrature point)

  • solution : handle to the MagneticsSolution used

  • timestamps : time-step timestamps in seconds

** volume_multiplier : model.dimensions.leff ** model.symmetrySectors

  • DETF : absolute value of mesh mapping matrix determinant at quad point

  • Bx : waveform of x-component of flux density at quad point

  • By : waveform of y-component of flux density at quad point

.parsing

.MaterialBase/init_for_problem is a function.

obj = MaterialBase

.intrinsic_coercivity_at_temperature Intrinsic coercivity at

given temperature.

HcJ = intrinsic_coercivity_at_temperature(this, T) returns the intrinsic coercivity HcJ (A/m) at the given temperature T (C).

.loss_density Iron/material loss density method.

[p_hysteresis, p_eddy, p_excess] = loss_density(this, Bdata), where

  • Bdata : flux density waveform data returned by get_B_data .

Return values:

  • Elementwise hysteresis, eddy, and exces loss densities, expressed in W/m^3.

.losses Material-level loss computation.

[Ptot, Pdata] = losses(solution) or

[Ptot, Pdata] = losses(solution, key, value, …) (see below)

return the total material (usually iron) losses Ptot for MagneticsSolution solution.

Pdata is then a struct with the following fields:

Return values: total losses (time-average) and a loss data struct with the following fields:

  • P_total : average total losses

  • P_total_time : total losses versus time (solution.ts)

  • P_hysteresis : total hysteresis losses

  • P_eddy : total eddy-current iron losses

  • P_excess : total excess losses.

  • P_rotor : total losses in rotor (in elements motor.rotel)

  • P_hysteresis_rotor : total hysteresis losses in rotor

  • P_eddy_rotor

  • p_hysteresis_elementwise : vector of elementwise hysteresis loss density (W/m^3)

  • p_eddy_elementwise

  • p_excess_elementwise

WARNING: element-wise loss densities are returned in W/m^3, as opposed to the W/kg used in previous versions.

The losses are computed by first computing the flux density waveforms with MaterialBase.get_B_data, and then passing the results to the .loss_density method of each Material in the solution, to get the elementwise loss densities. The losses are then summed and the other interesting outputs computed.

Keyword arguments:

  • plotting_on : plot results (default false). Losses are plotted with MaterialBase.plot_losses

  • remove_DC : Remove DC-component of flux density before computing losses? Options: false - no removal / ‘rotor’ - only remove from rotor elements (motor.rotel) / ‘all’ remove from all elements.

  • use_entire_solution : use entire solution range (in time-domain). Default: false: only last full electrical period is used.

  • method : This value is temporarily set as the iron_loss_computation_method property of each Material. For the plain Material class, the options are “iron_loss_density_time_domain_Steinmetz” and “iron_loss_density_frequency_domain_Bertotti”. Subclasses may ignore this. Default : [] –> don’t change the property value.

.MaterialBase/plot_BH is a function.

obj = MaterialBase

.MaterialBase.plot_losses is a function.

MaterialBase.plot_losses(solution, Pdata, varargin)

.MaterialBase/raw_reluctivity is a function.

obj = MaterialBase

.remanence_flux_density_at_temperature Remanence flux density

at given temperature.

Br = remanence_flux_density_at_temperature(this, T) returns the remanence flux density (T) at a the given temperature T (C).