Projects and Objectives

A manufacturer of aircraft, during the development of a new series, needed to simulate the entire system to ensure performance, verify compliance with EASA (European Union Aviation Safety Agency) requirements, and identify potential improvements to optimize overall efficiency. For these detailed analyses, the company relied on BSIM and its simulation consulting services.

Approach to Analysis

A three-dimensional mapping of the aircraft’s fuel tanks was developed, allowing for dynamic analysis of the liquid levels and the flows between the various sections of the tanks. This approach makes it possible to account for the influence of the aircraft’s maneuvers on the fluid dynamics inside the tanks, ensuring a detailed analysis of their operation under variable operating conditions.

Graphical Reconstruction of the Aircraft in Amesim

Figure 1: 3D Visualization of the Aircraft in Amesim

Thanks to BSIM’s extensive experience in 0D/1D fluid dynamics simulation, its technicians developed a complete model of the Aircraft Fuel System (ACF) for the aircraft. To ensure an accurate representation of the system’s behavior, the manufacturer’s original tables were imported for the modeling of engine logics and all auxiliary services connected to the ACF system, including the ventilation system, emergency fuel dumping systems, and fuel refueling control logics.

The model, created using components available in Amesim, enabled the implementation of all parameters related to the aircraft’s speed, acceleration, and rotation angles, while accounting for altitude variations and the corresponding changes in pressure and temperature, in accordance with the ISA76 standard (US Standard Atmosphere 1976).

Amesim Sketch

Figure 2: Sketch of the Aircraft’s ACF System

The experimental data provided by the client were used to calibrate the numerical model, turning it into a digital twin of the real system.

Figure 3: Calibration Test of the Amesim Model

Once calibrated, the Amesim model was used to perform 0D CFD simulations under extreme operating conditions, with the goal of identifying potential critical issues in the aircraft. This process allowed for the identification of problematic areas and the proposal of improvement solutions.

Figure 4: Aircraft Optimization Simulations

The various optimization proposals were discussed with the client and selected based on technical feasibility and cost. The approved solutions were implemented and tested in Amesim using the previously calibrated numerical model, with the goal of evaluating performance improvements. The optimal solution was ultimately implemented by the client, who was able to confirm compliance with the EASA requirements necessary to obtain flight certification.

Future Developments

As the next step, it was decided to implement secondary systems to further optimize the performance of the ACF system, ensuring greater stability even under extreme operating conditions, which are difficult to replicate through experimental tests without risking potential damage to the aircraft and thus keeping personnel safe.

Thanks to these simulations, the client gained a deeper understanding of the overall operation of the aircraft. A particularly significant test involved verifying the absence of cavitation in the ejector pumps during a simulated flight cycle.

Conclusion

The client successfully implemented the modifications proposed by BSIM, achieving an optimized configuration that resolved the previously identified issues. The analysis carried out in Amesim made it possible to identify and implement the best solutions to improve the overall performance of the aircraft, ensuring compliance with EASA requirements. This process enabled the client to gain a detailed understanding of the bottlenecks that were limiting efficiency and to make targeted adjustments, resulting in significant improvements in both the performance and safety of the aircraft.