SPM_RPM_Limit Analyzer (#271)

* Add rotor_speed_limit analyzer script * Edit rotor_speed_limit.py * Edit rotor_speed_limit.py * Edit rotor_speed_limit.py * Edit rotor_speed_limit.py * Edit rotor_speed_limit.py * Edit rotor_speed_limit.py * Edit rotor_speed_limit.py * Edit rotor_speed_limit.py * Edit rotor_speed_limit.py * Add comments * Add new methods * Rename methods and resturctured rotor_speed_limit.py * Add additional comments * modify rotor_speed_limit.py and convert stress values to class properties * edit left and right side bar padding * edit code comment * fix typo in rotor_speed_limit analyzer doc string and add rst file * add rotor speed limit analyzer to index.rst * add rotor_speed_limit example into example folder * merge new develop into local branch and make grammatical changes * add no sleeve example for SPM rotor speed limit analyzer documenation * edit SPM_rotor_speed_limit_analyzer documnetation and add no sleeve code * change name of example script * rearrange section and fix typos in .rst file * Add results class * fix rotor_speed_limit.py result class call location, edit example code * modify .rst and example script for SPM rotor speed limit analyzer to reflect the new result class * fix grammatical and spelling errors in .rst file * resolve conflicts and rearrange results section of .rst file * Fix indexing file * address .rst to follow eMach analyzer guidelines * rearrange .rst file and add analyzer inputs table * edit spm_rpm_limit * further edits to rotor speed limit --------- Co-authored-by: Anson Chan <[email protected]> Co-authored-by: Eric Severson <[email protected]>
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diff --git a/docs/source/mechanical_analyzers/SPM_rotor_speed_limit_analyzer.rst b/docs/source/mechanical_analyzers/SPM_rotor_speed_limit_analyzer.rst
@@ -0,0 +1,235 @@
+.. _rotor_speed_analyzer:
+
+
+SPM Rotor Speed Analyzer
+##############################
+
+This analyzer determines the failure speed of a surface-mounted permanent magnet (SPM) rotor design.  
+
+Model Background
+****************
+
+This analyzer utilizes the **SPM Rotor Structural Analyzer** to calculate the rotor's internal stresses over a specified range of rotational speeds. From this, the analyzer determines whether 
+the rotor will fail structurally using either maximum shear stress theory (MSST) or von Mises failure criterion based on the rotor material as follows:
+
+* von Mises is used for ductile materials, such as rotor shafts and rotor laminations
+* MSST is used for brittle materials [#]_ , such as adhesives and permanent magnets.
+
+Detailed descriptions of the **SPM Rotor Structural Analyzer** can be found on the analyzer page 
+`here <https://emach.readthedocs.io/en/latest/mechanical_analyzers/SPM_structural_analyzer.html#inputs-from-user>`_.
+
+.. [#]  Ideally, for brittle materials, Mohr–Coulomb theory should be used in determining failure. However, due to the lack of material data avaliable, MSST is used instead.
+
+Input from User
+**********************************
+
+The SPM rotor speed problem class requires the dimensions of the rotor shaft, the rotor material dictionary ``mat_dict``, the maximum evaluated speed in RPM 
+``N_max``, and the material failure dictionary ``mat_failure_dict``. For the required rotor shaft dimensions and rotor material dictionary ``mat_dict``, please refer 
+to the `Input from User  <https://emach.readthedocs.io/en/latest/mechanical_analyzers/SPM_structural_analyzer.html>`_ section in the **SPM Rotor Structural Analyzer** 
+documentation page.
+
+For the material failure strength dictionary ``mat_failure_dict``, the following key value pairs are needed. Notice that ductile materials require yield strength 
+while brittle materials require ultimate strength for failure criterion. The main table containing the necessary input variables can be seen in the inputs section of 
+the **SPM Rotor Structural Analyzer**, found `here <https://emach.readthedocs.io/en/latest/mechanical_analyzers/SPM_structural_analyzer.html#inputs-from-user>`_. The 
+additional parameters necessary for the yield and ultimate strengths can be found in the table below:
+
+.. _mat-failure-dict:
+.. csv-table:: ``mat_failure_dict`` input to SPM rotor speed limit problem
+   :file: inputs_mat_failure_dict_rotor_speed_limit.csv
+   :widths: 70, 70, 30
+   :header-rows: 1
+
+Additionally, the user must provide information to this analyzer's initializer, as indicated in the table below:
+
+.. _mat-failure-dict:
+.. csv-table:: input to SPM rotor speed limit analyzer
+   :file: inputs_rotor_speed_limit_analyzer.csv
+   :widths: 70, 70, 30
+   :header-rows: 1
+
+
+The analyzer runs through the code at incremental speed increases (``N_step``) to determine the failure speed and material. Since this analyzer only provides an estimate of RPM failure speed, the user is advised to use a coarse ``N_step`` value (such as 1000 RPM) to speed up the analysis. 
+For the ``node`` value, the user can also adjust accordingly based on their machine rotor size. In addition, the user should consider implementating a factor of safety 
+for the machine speed limit in their design.
+
+The following code demonstrates how to initialize the ``SPM_RotorSpeedLimitProblem`` class. The values used by the ``mat_dict`` are representative of typical values 
+used by this analyzer. This assumes 1045 carbon steel for the rotor shaft, M19 29-gauge laminated steel for the rotor core, N40 neodymium magnets, and carbon fiber 
+for the sleeve.
+
+.. code-block:: python
+
+   import numpy as np
+   from matplotlib import pyplot as plt
+   import eMach.mach_eval.analyzers.mechanical.rotor_speed_limit as rsl
+   ######################################################
+   # Creating the required Material Dictionary
+   ######################################################
+   mat_dict = {
+
+      # Material: M19 29-gauge laminated steel
+      'core_material_density': 7650,  # kg/m3
+      'core_youngs_modulus': 185E9,  # Pa
+      'core_poission_ratio': .3,
+      'alpha_rc' : 1.2E-5,
+
+      # Material: N40 neodymium magnets
+      'magnet_material_density'    : 7450, # kg/m3
+      'magnet_youngs_modulus'      : 160E9, # Pa
+      'magnet_poission_ratio'      :.24,
+      'alpha_pm'                   :5E-6,
+
+      # Material: Carbon Fiber
+      'sleeve_material_density'    : 1800, # kg/m3
+      'sleeve_youngs_th_direction' : 125E9,  #Pa
+      'sleeve_youngs_p_direction'  : 8.8E9,  #Pa
+      'sleeve_poission_ratio_p'    :.015,
+      'sleeve_poission_ratio_tp'   :.28,
+      'alpha_sl_t'                :-4.7E-7,
+      'alpha_sl_r'                :0.3E-6,
+
+      'sleeve_max_tan_stress': 1950E6,  # Pa
+      'sleeve_max_rad_stress': -100E6,  # Pa
+
+      # Material: 1045 carbon steel
+      'shaft_material_density': 7870,  # kg/m3
+      'shaft_youngs_modulus': 206E9,  # Pa
+      'shaft_poission_ratio': .3,  # []
+      'alpha_sh' : 1.2E-5
+   }
+
+   ######################################################
+   # Creating the required Material Yield Stength Dictionary
+   ######################################################
+
+   # Sources
+   # Steel: https://www.matweb.com/search/DataSheet.aspx?MatGUID=e9c5392fb06542ca95dcce43149106ac
+   # Magnet: https://www.matweb.com/search/DataSheet.aspx?MatGUID=b9cac0b8154f4718859da1fe3cdc3c90
+   # Sleeve: https://www.matweb.com/search/datasheet.aspx?matguid=f0231febe90f4b45857f543bb3300f27
+   # Shaft: https://www.matweb.com/search/DataSheet.aspx?MatGUID=b194a96080b6410ba81734b094a4537c
+
+   mat_failure_dict = {
+
+      # Material: M19 29-gauge laminated steel
+      # Failure Mode: Yield
+      'core_yield_strength': 359E6,   # Pa
+
+      # Material: N40 neodymium magnets
+      # Failure Mode: Ultimate
+      'magnet_ultimate_strength': 80E6,   # Pa
+
+      # Material: Carbon Fiber
+      # Failure Mode: Ultimate
+      'sleeve_ultimate_strength': 1380E6, # Pa
+
+      # Material: 1045 carbon steel
+      # Failure Mode: Yield
+      'shaft_yield_strength': 405E6,  # Pa
+
+      # Material: LOCTITE® AA 332™
+      # Failure Mode: At break (Ultimate)
+      'adhesive_ultimate_strength': 17.9E6,  # Pa
+   }
+
+Example with Rotor Sleeve
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The following code provides an example of a rotor without a rotor sleeve:
+
+.. code-block:: python
+
+   ######################################################
+   #Setting the machine geometry and operating conditions
+   ######################################################
+   r_sh = 5E-3 # [m]
+   d_m = 2E-3 # [m]
+   r_ro = 12.5E-3 # [m]
+   deltaT = 0 # [K]
+   N_max = 100E3 # [RPM]
+   d_sl=1E-3 # [m]
+   delta_sl=-2.4E-5 # [m]
+
+   ######################################################
+   #Creating problem
+   ######################################################
+   problem = rsl.SPM_RotorSpeedLimitProblem(r_sh, d_m, r_ro, d_sl, delta_sl, deltaT, 
+                                        N_max, mat_dict, mat_failure_dict)
+
+   ######################################################
+   #Creating analyzer class
+   ######################################################
+   analyzer = rsl.SPM_RotorSpeedLimitAnalyzer(N_step=100,node=1000)
+
+
+Example with No Rotor Sleeve
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+To analyze a rotor with no sleeve, a simple set of ``d_sl``, ``delta_sl``, and ``deltaT`` are required when creating the problem. This is shown in the following code:
+
+.. code-block:: python
+
+   ######################################################
+   #Setting the machine geometry and operating conditions
+   ######################################################
+   r_sh = 5E-3 # [m]
+   d_m = 2E-3 # [m]
+   r_ro = 12.5E-3 # [m]
+   deltaT = 0 # [K]
+   N_max = 100E3 # [RPM]
+   d_sl=0 # [m]
+   delta_sl=0 # [m]
+
+   ######################################################
+   #Creating problem
+   ######################################################
+   problem = rsl.SPM_RotorSpeedLimitProblem(r_sh, d_m, r_ro, d_sl, delta_sl, deltaT, 
+                                        N_max, mat_dict, mat_failure_dict)
+
+   ######################################################
+   #Creating analyzer class
+   ######################################################
+   analyzer = rsl.SPM_RotorSpeedLimitAnalyzer(N_step=100,node=1000)
+
+
+Output to User
+***********************************
+
+The attributes of the results class can be summarized in the table below:
+
+.. csv-table::  results of SPM rotor speed limit analyzer
+   :file: results_SPM_rotor_speed_limit_analyzer.csv
+   :widths: 70, 70, 30
+   :header-rows: 1
+
+Use the following code to run the aforementioned example analysis:
+
+.. code-block:: python
+
+   result = analyzer.analyze(problem)
+   print(result.failure_mat)
+   print(result.speed)
+
+When a certain material in the rotor reaches the failure criterion, the script will break out of the loop and return an instance of the results class with the attributes
+diagrammed in the table above. Within the results class, ``failure_mat`` is the failure material (type: str) and ``speed`` is the failure speed (type: float).
+
+Example with Rotor Sleeve
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Running the example case with a rotor sleeve returns the following:
+
+.. code-block:: python
+
+   None
+   None
+
+indicating no failure is found in speeds tested below the maximum speed ``N_max`` given by the user.
+
+
+Example with No Rotor Sleeve
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Running the example case with no rotor sleeve returns the following:
+
+.. code-block:: python
+
+   'Adhesive'
+   77700.0
+
+indicating a failure with the adhesive at 77700 RPM.
diff --git a/docs/source/mechanical_analyzers/index.rst b/docs/source/mechanical_analyzers/index.rst
@@ -15,3 +15,4 @@ This page contains links to analyzers in eMach which aid in evaluating the mecha
     Inner Rotor Stator Thermal <inner_rotor_stator_thermal_analyzer>
     SPM Rotor Structural <SPM_structural_analyzer>
     SPM Sleeve <SPM_sleeve_analyzer>
+    SPM Rotor Speed <SPM_rotor_speed_limit_analyzer>
diff --git a/docs/source/mechanical_analyzers/inputs_mat_failure_dict_rotor_speed_limit.csv b/docs/source/mechanical_analyzers/inputs_mat_failure_dict_rotor_speed_limit.csv
@@ -0,0 +1,6 @@
+Argument,Description,Units
+core_yield_strength,Rotor iron core yield strength,Pa
+magnet_ultimate_strength,Magnet ultimate strength,Pa
+sleeve_ultimate_strength,Sleeve ultimate strength,Pa
+shaft_yield_strength,Rotor shaft yield strength,Pa
+adhesive_ultimate_strength,Adhesive ultimate strength ,Pa
diff --git a/docs/source/mechanical_analyzers/inputs_rotor_speed_limit_analyzer.csv b/docs/source/mechanical_analyzers/inputs_rotor_speed_limit_analyzer.csv
@@ -0,0 +1,3 @@
+Argument,Description,Units
+N_step,Evaluation step size,RPM
+node,Number of nodes to evaluate stress at,
diff --git a/docs/source/mechanical_analyzers/results_SPM_rotor_speed_limit_analyzer.csv b/docs/source/mechanical_analyzers/results_SPM_rotor_speed_limit_analyzer.csv
@@ -0,0 +1,3 @@
+Attribute/function name,Description,Units
+failure_mat,material in which failure occurs,
+speed,speed at which failure occurs,RPM
diff --git a/examples/mach_eval_examples/bspm_eval/rotor_speed_limit_script.py b/examples/mach_eval_examples/bspm_eval/rotor_speed_limit_script.py
@@ -0,0 +1,118 @@
+import sys
+import os
+
+# add the directory 3 levels above this file's directory to path for module import
+sys.path.append(os.path.dirname(__file__)+"/../../..")
+sys.path.append(os.path.dirname(__file__))
+
+from mach_eval.analyzers.mechanical.rotor_speed_limit import SPM_RotorSpeedLimitAnalyzer, SPM_RotorSpeedLimitProblem
+
+def example():
+    """Example Problem"""
+    ######################################################
+    # Creating the required Material Dictionary
+    ######################################################
+    mat_dict = {
+
+        # Material: M19 29-gauge laminated steel
+        'core_material_density': 7650,  # kg/m3
+        'core_youngs_modulus': 185E9,  # Pa
+        'core_poission_ratio': .3,
+        'alpha_rc' : 1.2E-5,
+
+        # Material: N40 neodymium magnets
+        'magnet_material_density'    : 7450, # kg/m3
+        'magnet_youngs_modulus'      : 160E9, # Pa
+        'magnet_poission_ratio'      :.24,
+        'alpha_pm'                   :5E-6,
+
+        # Material: Carbon Fiber
+        'sleeve_material_density'    : 1800, # kg/m3
+        'sleeve_youngs_th_direction' : 125E9,  #Pa
+        'sleeve_youngs_p_direction'  : 8.8E9,  #Pa
+        'sleeve_poission_ratio_p'    :.015,
+        'sleeve_poission_ratio_tp'   :.28,
+        'alpha_sl_t'                :-4.7E-7,
+        'alpha_sl_r'                :0.3E-6,
+
+        'sleeve_max_tan_stress': 1950E6,  # Pa
+        'sleeve_max_rad_stress': -100E6,  # Pa
+
+        # Material: 1045 carbon steel
+        'shaft_material_density': 7870,  # kg/m3
+        'shaft_youngs_modulus': 206E9,  # Pa
+        'shaft_poission_ratio': .3,  # []
+        'alpha_sh' : 1.2E-5
+    }
+
+    ######################################################
+    # Creating the required Material Yield Stength Dictionary
+    ######################################################
+
+    # Sources
+    # Steel: https://www.matweb.com/search/DataSheet.aspx?MatGUID=e9c5392fb06542ca95dcce43149106ac
+    # Magnet: https://www.matweb.com/search/DataSheet.aspx?MatGUID=b9cac0b8154f4718859da1fe3cdc3c90
+    # Sleeve: https://www.matweb.com/search/datasheet.aspx?matguid=f0231febe90f4b45857f543bb3300f27
+    # Shaft: https://www.matweb.com/search/DataSheet.aspx?MatGUID=b194a96080b6410ba81734b094a4537c
+
+    mat_failure_dict = {
+
+        # Material: M19 29-gauge laminated steel
+        # Failure Mode: Yield
+        'core_yield_strength': 359E6,   # Pa
+
+        # Material: N40 neodymium magnets
+        # Failure Mode: Ultimate
+        'magnet_ultimate_strength': 80E6,   # Pa
+
+        # Material: Carbon Fiber
+        # Failure Mode: Ultimate
+        'sleeve_ultimate_strength': 1380E6, # Pa
+
+        # Material: 1045 carbon steel
+        # Failure Mode: Yield
+        'shaft_yield_strength': 405E6,  # Pa
+
+        # Material: LOCTITE® AA 332™
+        # Failure Mode: At break (Ultimate)
+        'adhesive_ultimate_strength': 17.9E6,  # Pa
+    }
+
+    #####################################################################
+    #Setting the machine geometry and operating conditions (NO SLEEVE)
+    #####################################################################
+    r_sh = 5E-3 # [m]
+    d_m = 2E-3 # [m]
+    r_ro = 12.5E-3 # [m]
+    deltaT = 0 # [K]
+    N_max = 100E3 # [RPM]
+    d_sl=0 # [m]
+    delta_sl=0 # [m]
+
+#    #####################################################################
+#    #Setting the machine geometry and operating conditions (W/ SLEEVE)
+#    #####################################################################
+#    r_sh = 5E-3 # [m]
+#    d_m = 2E-3 # [m]
+#    r_ro = 12.5E-3 # [m]
+#    deltaT = 0 # [K]
+#    N_max = 100E3 # [RPM]
+#    d_sl=1E-3 # [m]
+#    delta_sl=-2.4E-5 # [m]
+
+    ######################################################
+    #Creating problem and analyzer class
+    ######################################################
+    problem = SPM_RotorSpeedLimitProblem(r_sh, d_m, r_ro, d_sl, delta_sl, deltaT, 
+                                        N_max, mat_dict, mat_failure_dict)
+
+    analyzer = SPM_RotorSpeedLimitAnalyzer(N_step=100,node=1000)
+    result = analyzer.analyze(problem)
+
+    print(result.failure_mat)
+    print(result.speed)
+
+if __name__ == '__main__': 
+    # Run this script to run the example case
+    example()
+