Anto01
2b3573ec42
Major additions: - Training data export system for AtomizerField neural network training - Bracket stiffness optimization study with 50+ training samples - Intelligent NX model discovery (auto-detect solutions, expressions, mesh) - Result extractors module for displacement, stress, frequency, mass - User-generated NX journals for advanced workflows - Archive structure for legacy scripts and test outputs - Protocol documentation and dashboard launcher 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
106 lines
3.4 KiB
Python
106 lines
3.4 KiB
Python
"""
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Extract maximum von Mises stress from structural analysis
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Auto-generated by Atomizer Phase 3 - pyNastran Research Agent
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Pattern: solid_stress
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Element Type: CTETRA
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Result Type: stress
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API: model.ctetra_stress[subcase] or model.chexa_stress[subcase]
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"""
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from pathlib import Path
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from typing import Dict, Any
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import numpy as np
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from pyNastran.op2.op2 import OP2
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def extract_solid_stress(op2_file: Path, subcase: int = 1, element_type: str = 'ctetra'):
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"""Extract stress from solid elements."""
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from pyNastran.op2.op2 import OP2
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import numpy as np
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model = OP2()
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model.read_op2(str(op2_file))
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# Get stress object for element type
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# Different element types have different stress attributes
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stress_attr_map = {
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'ctetra': 'ctetra_stress',
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'chexa': 'chexa_stress',
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'cquad4': 'cquad4_stress',
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'ctria3': 'ctria3_stress'
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}
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stress_attr = stress_attr_map.get(element_type.lower())
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if not stress_attr:
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raise ValueError(f"Unknown element type: {element_type}")
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# Access stress through op2_results container
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# pyNastran structure: model.op2_results.stress.cquad4_stress[subcase]
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stress_dict = None
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if hasattr(model, 'op2_results') and hasattr(model.op2_results, 'stress'):
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stress_container = model.op2_results.stress
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if hasattr(stress_container, stress_attr):
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stress_dict = getattr(stress_container, stress_attr)
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if stress_dict is None:
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raise ValueError(f"No {element_type} stress results in OP2. Available attributes: {[a for a in dir(model) if 'stress' in a.lower()]}")
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# stress_dict is a dictionary with subcase IDs as keys
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available_subcases = list(stress_dict.keys())
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if not available_subcases:
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raise ValueError(f"No stress data found in OP2 file")
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# Use the specified subcase or first available
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if subcase in available_subcases:
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actual_subcase = subcase
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else:
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actual_subcase = available_subcases[0]
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stress = stress_dict[actual_subcase]
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itime = 0
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# Extract von Mises if available
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if stress.is_von_mises: # Property, not method
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# Different element types have von Mises at different column indices
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# Shell elements (CQUAD4, CTRIA3): 8 columns, von Mises at column 7
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# Solid elements (CTETRA, CHEXA): 10 columns, von Mises at column 9
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ncols = stress.data.shape[2]
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if ncols == 8:
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# Shell elements - von Mises is last column
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von_mises_col = 7
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elif ncols >= 10:
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# Solid elements - von Mises is column 9
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von_mises_col = 9
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else:
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# Unknown format, try last column
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von_mises_col = ncols - 1
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von_mises = stress.data[itime, :, von_mises_col]
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max_stress = float(np.max(von_mises))
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# Get element info
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element_ids = [eid for (eid, node) in stress.element_node]
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max_stress_elem = element_ids[np.argmax(von_mises)]
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return {
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'max_von_mises': max_stress,
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'max_stress_element': int(max_stress_elem)
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}
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else:
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raise ValueError("von Mises stress not available")
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if __name__ == '__main__':
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# Example usage
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import sys
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if len(sys.argv) > 1:
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op2_file = Path(sys.argv[1])
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result = extract_solid_stress(op2_file)
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print(f"Extraction result: {result}")
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else:
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print("Usage: python {sys.argv[0]} <op2_file>")
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