mach_eval.analyzers.mechanical package

thermal_network module

class mach_eval.analyzers.mechanical.thermal_network.Material(k: float, cp: float = 0.0, mu: float = 0.0)

Bases: object

Class holding material parameters.

k: Thermal conductivity [W/m-K]

cp: cp value of fluid []

mu: Viscosity of fluid []

class mach_eval.analyzers.mechanical.thermal_network.Resistance(Material: Material, Node1: int, Node2: int)

Bases: object

Base class for thermal resisance

Material: Material object holding material properties

Node1: First node connected to resistance

Node2: Second node connected to resistance

resistance_value: Thermal resistance [K/W]

property resistance_value

class mach_eval.analyzers.mechanical.thermal_network.ThermalNetworkAnalyzer

Bases: object

Thermal Resistance Network Analyzer.

analyze(problem: ThermalNetworkProblem)

Analyze imported resistance network problem

Parameters:: problem – ThermalNetworkProblem object to be analyzed
Returns:: Temperature distribution at each node in system
Return type:: T

class mach_eval.analyzers.mechanical.thermal_network.ThermalNetworkProblem(res: List[Resistance], Q_dot: List[float], T_ref: List[List[int, float]], N_nodes: int)

Bases: object

Problem class from Thermal Resistance Network Analyzer.

res: List of Resistance objects

Q_dot: List of Thermal sources at nodal locations

T_ref: List of [ref_node,ref_temp]

N_nodes: Number of Nodes in system

class mach_eval.analyzers.mechanical.thermal_network.air_gap_conv(Material: Material, Node1: int, Node2: int, omega: float, R_r: float, R_s: float, u_z: float, A: float)

Bases: Resistance

Air gap convection thermal resistance

Material: Material object holding material properties

Node1: First node connected to resistance

Node2: Second node connected to resistance

resistance_value: Thermal resistance [K/W]

omega: rotational speed [rad/s]

R_r: Rotor outer radius [m]

R_s: Stator inner radius [m]

u_z: Axial airflow speed [m/s]

A: Cross sectional area [m^2]

h: Convection Coeff [W/m^2-K]

property h

property resistance_value

class mach_eval.analyzers.mechanical.thermal_network.conv(Material: Material, Node1: int, Node2: int, h: float, A: float)

Bases: Resistance

Air gap convection thermal resistance

Material: Material object holding material properties

Node1: First node connected to resistance

Node2: Second node connected to resistance

resistance_value: Thermal resistance [K/W]

A: Cross sectional area [m^2]

h: Convection Coeff [W/m^2-K]

property h

property resistance_value

class mach_eval.analyzers.mechanical.thermal_network.cylind_wall(Material: Material, Node1: int, Node2: int, R1: float, R2: float, H: float)

Bases: Resistance

Cylindrical wall thermal resistance.

Material: Material object holding material properties

Node1: First node connected to resistance

Node2: Second node connected to resistance

resistance_value: Thermal resistance [K/W]

R1: Radial position of node-1 [m]

R2: Radial position of node-2 [m]

H: Height of wall [m]

property resistance_value

class mach_eval.analyzers.mechanical.thermal_network.hub_conv(Material: Material, Node1: int, Node2: int, omega: float, A: float)

Bases: Resistance

Hub convection thermal resistance

Material: Material object holding material properties

Node1: First node connected to resistance

Node2: Second node connected to resistance

resistance_value: Thermal resistance [K/W]

omega: rotational speed [rad/s]

A: Cross sectional area [m^2]

h: Convection Coeff [W/m^2-K]

property h

property resistance_value

class mach_eval.analyzers.mechanical.thermal_network.plane_wall(Material: Material, Node1: int, Node2: int, L: float, A: float)

Bases: Resistance

Plane wall thermal resistance.

Material: Material object holding material properties

Node1: First node connected to resistance

Node2: Second node connected to resistance

resistance_value: Thermal resistance [K/W]

L1: Position of node-1 [m]

L2: Position of node-2 [m]

A: Cross sectional area [m^2]

property resistance_value

class mach_eval.analyzers.mechanical.thermal_network.shaft_conv(Material: Material, Node1: int, Node2: int, omega: float, R: float, A: float, u_z: float)

Bases: Resistance

Shaft convection thermal resistance

Material: Material object holding material properties

Node1: First node connected to resistance

Node2: Second node connected to resistance

resistance_value: Thermal resistance [K/W]

omega: rotational speed [rad/s]

R: Shaft outer radius [m]

u_z: Axial airflow speed [m/s]

A: Cross sectional area [m^2]

h: Convection Coeff [W/m^2-K]

Re: Reynolds number []

Pr: Prandlt number []

Nu: Nusselt number []

property Nu

property Pr

property Re

property h

property resistance_value

rotor_thermal module

class mach_eval.analyzers.mechanical.rotor_thermal.AirflowAnalyzer

Bases: object

Analyzer to calculate required airflow in SPM machine

analyze(problem: AirflowProblem)

Analyzes input problem to calculate required airflow to cool rotor

Parameters:: problem (AirflowProblem) – input problem
Returns:: dictionary with analyzer solution
Return type:: results (dict)

class mach_eval.analyzers.mechanical.rotor_thermal.AirflowProblem(r_sh: float, d_ri: float, r_ro: float, d_sl: float, r_si: float, l_st: float, l_hub: float, T_ref: float, losses: dict, omega: float, max_temp: float, mat_dict: dict)

Bases: object

Problem class for AirflowAnalyzer

mat_dict

Material Dictionary

Type:: dict

r_sh

Shaft radius [m]

Type:: float

d_ri

Back iron thickness [m]

Type:: float

r_ro

Outer rotor radius [m]

Type:: float

d_sl

Sleeve Thickness [m]

Type:: float

r_si

Stator Inner radius [m]

Type:: float

l_st

Stack length [m]

Type:: float

l_hub

hub thickness [m]

Type:: float

T_ref

Air Temperature [C]

Type:: float

losses

Loss dictionary [W]

Type:: dict

omega

Rotational Speed [rad/s]

Type:: float

max_temp

Max rotor magnet temperature [K]

Type:: float

therm_prob

Thermal problem to solve

Type:: Problem

therm_ana

Analyzer to solve problem

Type:: Analzyer

cost(u_z): Returns airflow rate as cost function

magnet_temp(u_z)

Calculate magnet temperature from airflow rate

Parameters:: u_z (float) – Axial airflow rate [m/s]
Returns:: Magnet Temperature
Return type:: T[5] (float)

class mach_eval.analyzers.mechanical.rotor_thermal.SPM_RotorThermalAnalyzer

Bases: object

Analyzer for rotor thermal problem

base_ana

Thermal Network Analyzer

Type:: tb.ThermalNetworkAnalyzer

analyze(problem: SPM_RotorThermalProblem)

Analyzes input problem for temperature distribution

Parameters:: problem (SPM_RotorThermalProblem) – input problem
Returns:: Temperature distribuiton in rotor
Return type:: T (List)

create_resistance_network(problem)

class mach_eval.analyzers.mechanical.rotor_thermal.SPM_RotorThermalProblem(mat_dict: dict, r_sh: float, d_ri: float, r_ro: float, d_sl: float, r_si: float, l_st: float, l_hub: float, T_ref: float, u_z: float, losses: dict, omega: float)

Bases: object

Problem class for rotor thermal analyzer

mat_dict

Material Dictionary

Type:: dict

r_sh

Shaft radius [m]

Type:: float

d_ri

Back iron thickness [m]

Type:: float

r_ro

Outer rotor radius [m]

Type:: float

d_sl

Sleeve Thickness [m]

Type:: float

r_si

Stator Inner radius [m]

Type:: float

l_st

Stack length [m]

Type:: float

l_hub

hub thickness [m]

Type:: float

T_ref

Air Temperature [C]

Type:: float

u_z

Axial air flow speed [m/s]

Type:: float

losses

Loss dictionary [W]

Type:: dict

omega

Rotational Speed [rad/s]

Type:: float

R_1

Shaft radius [m]

Type:: float

R_2

Back iron radius [m]

Type:: float

R_3

Outer rotor Radius [m]

Type:: float

R_4

Outer sleeve radius [m]

Type:: float

windage_loss module

class mach_eval.analyzers.mechanical.windage_loss.WindageLossAnalyzer

Bases: object

Windage loss analyzer

analyze()

Calculates total windage loss in machine.

Parameters:: problem – problem class
Returns:: Total windage loss on rotor
Return type:: windage_loss_total

class mach_eval.analyzers.mechanical.windage_loss.WindageLossProblem(Omega, R_ro, stack_length, R_st, u_z, T_air=25)

Bases: object

Problem analyzer for windage anlyzer .. attribute:: Omega

rotational speed [rad/s]

R_ro: outer rotor radius [m]

stack_length: stack length [m]

R_st: inner stator radius [m]

air_gap: airgap length [m]

u_z: axial air flow speed [m/s]

T_air: Air temperature

thermal_stator module

class mach_eval.analyzers.mechanical.thermal_stator.StatorThermalAnalyzer

Bases: object

“Stator Thermal Analyzer calculates coil temperatures

analyze(problem)

calculates coil temperature from problem class.

Parameters:: problem (StatorThermalProblem) – Problem Object
Returns:: Dict of coil and stator yoke temperature
Return type:: results

class mach_eval.analyzers.mechanical.thermal_stator.StatorThermalProblem(g_sy: float, g_th: float, w_tooth: float, l_st: float, alpha_q: float, r_si: float, r_so: float, r_sy: float, k_ins: float, w_ins: float, k_fe: float, h: float, alpha_slot: float, Q_coil: float, h_slot: float, T_ref: float)

Bases: object

Problem class utilized by the stator thermal analyzer

g_sy: Volumetric Heating of stator yoke [W/m^3]

g_th: Volumetric Heating of stator tooth [W/m^3]

w_tooth: Width of stator tooth [m]

l_st: Stack length [m]

l_tooth: Length of stator tooth [m]

alpha_q: slot span 2pi/Q [rad]

r_si: Inner stator radius [m]

r_so: Outer stator radius [m]

r_sy: Radius of inner stator yoke [m]

k_ins: Thermal conductivity of insulation paper [W/m-K]

w_ins: Thickness of Insulation paper [m]

k_fe: Thermal conductivty of stator iron [W/m-K]

h: Convection rate on exterior of stator [W/m^2-K]

alpha_slot: Angle of back of slot on stator yoke [rad]

T_coil_max: Maximum coil temperature [K]

r_si: Inner stator radius [m]

Q_coil: Resistive coil losses [W]

h_slot: Inslot convection rate [W/m^2-K]

T_ref: Refrence temperature

rotor_structural module

class mach_eval.analyzers.mechanical.rotor_structural.Material_Isotropic(Density, ElasticMod, PoissonRatio, alpha)

Bases: object

property C1

property C2

property C3

property Del

property h

property zeta_r

property zeta_t

property zeta_u

class mach_eval.analyzers.mechanical.rotor_structural.Material_Transverse_Isotropic(Density, ElasticMod_Thread, ElasticMod_Plane, PoissonRatio_tp, PoissonRatio_p, alpha_r, alpha_t)

Bases: object

property C1

property C2

property C3

property Del

property Nu_pt

property h

property zeta_r

property zeta_t

property zeta_u

class mach_eval.analyzers.mechanical.rotor_structural.RotorComponent(MaterialObject, InnerRadius, OuterRadius)

Bases: object

property Beta

set_MaxRadialStress(sigmaMax)

set_MaxTanStress(sigmaMax)

set_delta_sl(Dr)

set_th(th)

class mach_eval.analyzers.mechanical.rotor_structural.SPM_RotorSleeveAnalyzer(stress_limits: List[float, float, float, float])

Bases: object

Analyzer for designing a rotor sleeve

stress_limits: list of limits for critical stresses

analyze(problem: SPM_RotorSleeveProblem)

analyzes input problem to design optimal rotor sleeve

Parameters:: problem (SPM_RotorSleeveProblem) – input problem
Returns:: solution from design problem
Return type:: sol

cost(x)

returns sleeve thickness

Parameters:: x – tuple of sleeve thickness and undersize
Returns:: sleeve thickness
Return type:: x[0]

class mach_eval.analyzers.mechanical.rotor_structural.SPM_RotorSleeveProblem(r_sh: float, d_m: float, r_ro: float, deltaT: float, mat_dict: dict, N: float, problem_class=<class 'mach_eval.analyzers.mechanical.rotor_structural.SPM_RotorStructuralProblem'>, analyzer_class=<class 'mach_eval.analyzers.mechanical.rotor_structural.SPM_RotorStructuralAnalyzer'>)

Bases: object

rad_magnet(x): Calculate P_pm for given sleeve design

rad_sleeve(x): Calculate P_sl for given sleeve design

tan_magnet(x): Calculate sigma_t_pm_max for given sleeve design

tan_sleeve(x): Calculate sigma_t_sl_max for given sleeve design

class mach_eval.analyzers.mechanical.rotor_structural.SPM_RotorStructuralAnalyzer

Bases: object

DetermineCoeff(sh: RotorComponent, rc, pm, sl, deltaT, omega)

Deterimine coeffiecents for calculating stresses

Parameters:

sh (RotorComponent) – Shaft RotorComponent object.
rc (RotorComponent) – Rotor core RotorComponent object.
pm (RotorComponent) – Magnets RotorComponent object.
sl (RotorComponent) – Sleeve RotorComponent object.
deltaT (float) – Temperature rise in deg C.
omega (float) – rotational speed in rad/s.

Returns:

numpy array of stress coeffiecents.

Return type:

A (np.Array)

analyze(problem: SPM_RotorStructuralProblem) → Tuple[Sigma, Sigma, Sigma, Sigma]

Analyze structural problem

Parameters:: problem (SPM_RotorStructuralProblem) – problem for analyzer.
Returns:: Sigma objects
Return type:: results ([‘Sigma’,’Sigma’,’Sigma’,’Sigma’])

class mach_eval.analyzers.mechanical.rotor_structural.SPM_RotorStructuralProblem(r_sh: float, d_m: float, r_ro: float, d_sl: float, delta_sl: float, deltaT: float, N: float, mat_dict: dict)