Optimization of a helicopter's fuel system

The optimization of a helicopter's fuel system is crucial for enhancing operational safety, reliability, and lifecycle efficiency in mission-critical rotary-wing platforms. This thesis presents a comprehensive multidisciplinary approach to the design and evaluation of fuel system components, focusing on mechanical integrity, thermal behavior, flow performance, and system-level safety. The system is divided into six functional sub-systems: fuel storage, ventilation, feed, transfer, refuel/defuel, and gauging & management systems. Each sub-system is examined using a combination of analytical and numerical methods, including Finite Element Analysis (FEA), Computational Fluid Dynamics (CFD), thermodynamic modeling, and structural optimization. Life Cycle Cost (LCC) evaluations are conducted using MIL-HDBK-338B and cost-scaling principles derived from Thermal Design and Optimization by Bejan et al., ensuring economic feasibility throughout the system's lifespan. Safety and reliability assessments are performed using international aviation standards such as MIL-STD-882E, ARP 4761, ARP 4754 and MIL-STD-1629A. Analyses include Functional Hazard Assessment (FHA), Preliminary System Safety Assessment (PSSA), Fault Tree Analysis (FTA), and Failure Modes, Effects and Criticality Analysis (FMECA). The study provides detailed risk classifications, failure probabilities, and mitigation strategies for critical components such as flame arrestors, sump plates, booster pumps, and dump valves. The comparative analysis between field-deployed components and thesis-optimized alternatives reveals improvements in pressure resistance, thermal performance, crashworthiness, and maintainability. The total Life Cycle Cost of the optimized system is calculated as $212,285.272, reflecting significant potential for cost reduction through design improvements.