High-Bypass Turbofan Cycle Optimization

This project performs a parametric design optimization for a High-Bypass Turbofan Engine.

Using MATLAB's constrained nonlinear optimization solver (fmincon), the script determines the optimal thermodynamic cycle parameters to minimize Specific Fuel Consumption (SFC) while satisfying a strict Thrust requirement.

🎯 Project Objective

To find the design point that yields the maximum fuel efficiency (Minimum SFC) under the following operational constraint:

• Target Thrust: $T \geq 100 \text{ kN}$

⚙️ Design Variables & Bounds

The optimization algorithm manipulates 5 key engine cycle parameters within feasible engineering limits:

Variable	Description	Lower Bound	Upper Bound
$\dot{m}_0$	Mass Flow Rate (kg/s)	200	600
$\alpha$	Bypass Ratio (BPR)	1	14
$\pi_f$	Fan Pressure Ratio	1.3	4
$\pi_c$	Compressor Pressure Ratio	30	60
$T_{t4}$	Turbine Inlet Temp (K)	1600	2100

🧠 Methodology

• Thermodynamic Model: A 0-D parametric cycle analysis (Real Cycle) including component efficiencies ($\eta_c, \eta_t, \eta_b$, etc.) and polytropic losses.
• [cite_start]Solver: MATLAB fmincon with the Sequential Quadratic Programming (SQP) algorithm.
• Objective Function: $$\min f(x) = SFC = \frac{\dot{m}_f}{\text{Thrust}}$$

📊 Results

The optimization converged to the following design point:

• Min SFC: $0.4435 \text{ (kg/N/h)}$ (approx. scaled)
• Thrust: $100.00 \text{ kN}$ (Active Constraint)
• Turbine Inlet Temp: $2040 \text{ K}$
• Bypass Ratio: $2.39$

🚀 How to Run

1. Clone the repository.
2. Run Turbofan_Optimization.m in MATLAB.
3. The script will output the iteration history and final optimized parameters to the command window.

👤 Author

Kivanc Apaydin Aeronautical Engineering Student Project

📝 Note on Optimization Results (BPR)

You might observe that the optimized Bypass Ratio ($\approx 2.4$) appears lower than typical "High-Bypass" engines.

This is a physical result of the specific constraints defined in the problem:

• High Thrust Requirement: 100 kN at 12,000 m altitude.
• Limited Mass Flow: Upper bound of 600 kg/s.

To satisfy the high thrust demand with limited air mass flow at high altitude, the optimizer correctly converges to a High Specific Thrust cycle, which inherently requires a lower Bypass Ratio. Increasing the mass flow limit or reducing the thrust constraint would yield higher BPR values.