| """ |
| Aerospace Materials Database |
| ============================= |
| Real material properties for LTA vehicle shell feasibility analysis. |
| All values sourced from standard aerospace material references. |
| """ |
|
|
| from dataclasses import dataclass |
| from typing import Optional |
| from engine.buoyancy_calculator import compute_buoyancy |
| import math |
|
|
|
|
| @dataclass(frozen=True) |
| class Material: |
| name: str |
| category: str |
| density_kg_m3: float |
| yield_strength_MPa: float |
| description: str |
| color: str |
|
|
|
|
| MATERIALS = [ |
| Material("Aluminum 6061-T6", "Metal", 2700.0, 276.0, |
| "General aerospace structures", "#7EC8DB"), |
| Material("Aluminum 7075-T6", "Metal", 2810.0, 503.0, |
| "High-strength aerospace alloy", "#5BA4B5"), |
| Material("Titanium Ti-6Al-4V", "Metal", 4430.0, 880.0, |
| "Aerospace-grade titanium", "#A78BFA"), |
| Material("Steel AISI 4130", "Metal", 7850.0, 460.0, |
| "Chromoly steel, engine mounts", "#C75050"), |
| Material("Magnesium AZ31B", "Metal", 1770.0, 200.0, |
| "Lightweight aerospace alloy", "#4CAF7D"), |
| Material("Inconel 718", "Metal", 8190.0, 1034.0, |
| "Nickel superalloy", "#D4A847"), |
| Material("Carbon Fiber (CFRP)", "Composite", 1600.0, 600.0, |
| "Primary aerospace composite", "#E2E8F0"), |
| Material("Kevlar 49 (AFRP)", "Composite", 1440.0, 525.0, |
| "Aramid fiber, impact resistant", "#D4A847"), |
| Material("Fiberglass (GFRP)", "Composite", 2100.0, 340.0, |
| "Glass fiber reinforced polymer", "#4CAF7D"), |
| Material("Carbon Nanotube Sheet", "Exotic", 1300.0, 1000.0, |
| "Theoretical advanced material", "#FF9F7F"), |
| Material("Mylar (PET Film)", "Polymer", 1390.0, 55.0, |
| "Polyester film, balloon envelopes", "#7EC8DB"), |
| Material("Kapton (Polyimide)", "Polymer", 1420.0, 69.0, |
| "High-temperature polymer film", "#D4A847"), |
| Material("UHMWPE (Dyneema)", "Polymer", 970.0, 39.0, |
| "Ultra-high MW polyethylene", "#4CAF7D"), |
| Material("Graphene Sheet", "Exotic", 2267.0, 130000.0, |
| "Theoretical single-layer carbon", "#A78BFA"), |
| Material("Beryllium", "Exotic", 1850.0, 240.0, |
| "Lightweight metal, aerospace optics", "#C75050"), |
| ] |
|
|
| MATERIAL_LOOKUP = {m.name: m for m in MATERIALS} |
| MATERIAL_CATEGORIES = sorted(set(m.category for m in MATERIALS)) |
|
|
|
|
| def evaluate_material(material, outer_radius_m, thickness_m, |
| internal_pressure_Pa, atmospheric_pressure_Pa=101325.0): |
| """Evaluate feasibility of a material for given sphere parameters.""" |
| try: |
| result = compute_buoyancy( |
| outer_radius_m=outer_radius_m, |
| thickness_m=thickness_m, |
| material_density_kg_m3=material.density_kg_m3, |
| internal_pressure_Pa=internal_pressure_Pa, |
| atmospheric_pressure_Pa=atmospheric_pressure_Pa, |
| ) |
| delta_p = atmospheric_pressure_Pa - internal_pressure_Pa |
| r = result.geometry.inner_radius_m |
| t = thickness_m |
| pressure_stress_MPa = (delta_p * r) / (2.0 * t) / 1e6 |
| omega = result.balanced_rotational_speed_rad_s |
| rotational_stress_MPa = material.density_kg_m3 * (omega ** 2) * (r ** 2) / 1e6 |
| total_stress_MPa = pressure_stress_MPa + rotational_stress_MPa |
| safety_factor = material.yield_strength_MPa / total_stress_MPa if total_stress_MPa > 0 else float('inf') |
|
|
| return { |
| "material": material, |
| "result": result, |
| "feasible_buoyancy": result.buoyancy_state == "Positive Buoyancy", |
| "feasible_structural": safety_factor >= 1.5, |
| "feasible_overall": (result.buoyancy_state == "Positive Buoyancy") and (safety_factor >= 1.5), |
| "mass_available_kg": result.mass_available_kg, |
| "brs_rpm": result.balanced_rotational_speed_rpm, |
| "pressure_stress_MPa": pressure_stress_MPa, |
| "rotational_stress_MPa": rotational_stress_MPa, |
| "total_stress_MPa": total_stress_MPa, |
| "safety_factor": safety_factor, |
| } |
| except (ValueError, ZeroDivisionError): |
| return { |
| "material": material, "result": None, |
| "feasible_buoyancy": False, "feasible_structural": False, |
| "feasible_overall": False, "mass_available_kg": 0.0, |
| "brs_rpm": 0.0, "pressure_stress_MPa": 0.0, |
| "rotational_stress_MPa": 0.0, "total_stress_MPa": 0.0, |
| "safety_factor": 0.0, |
| } |
|
|
|
|
| def find_min_feasible_radius(material, thickness_m=0.0005, |
| internal_pressure_Pa=5066.25, |
| atmospheric_pressure_Pa=101325.0): |
| """Find minimum radius for positive buoyancy. Returns None if not feasible.""" |
| for r_10x in range(5, 500): |
| r = r_10x / 10.0 |
| try: |
| result = compute_buoyancy(r, thickness_m, material.density_kg_m3, |
| internal_pressure_Pa, atmospheric_pressure_Pa) |
| if result.buoyancy_state == "Positive Buoyancy": |
| return r |
| except (ValueError, ZeroDivisionError): |
| pass |
| return None |
|
|
