Graduation Internship: Aerodynamic Interactions on Lift-Plus-Cruise Aircraft

Background

Lift-plus-cruise  aircraft rely on multiple lifting components and distributed propulsion, resulting in complex aerodynamic interactions between rotors, wings, and fuselage. These interactions are particularly significant in the transitional speed regime, where both hover- and forward-flight aerodynamics contribute to the overall flow field.

Understanding the characteristics of these aerodynamic interferences is crucial for accurate prediction of airframe performance, flight dynamics, and aeroacoustic behaviour. Moreover, over-actuated trim control strategies influence how these interactions manifest in flight, potentially mitigating or exacerbating performance losses. Determining the required fidelity of aerodynamic modelling for predictive capability—including validation against wind-tunnel data—is essential for effective design and analysis.

Assignment

The aim of the assignment is to investigate and quantify the aerodynamic interaction effects in lift-plus aircraft, and assess the influence of trim control allocation on aircraft performance, flight dynamics, using multi-fidelity modelling and experimental validation.

Objectives

• Characterize aerodynamic interaction effects occurring in lift-plus-cruise configurations in the transitional speed regime, using both wind-tunnel measurements and computational modeling.

• Evaluate how trim control allocation of over-actuated aircraft influences the impact of these interactions on airframe performance, flight dynamics.

• Determine the level of aerodynamic modeling fidelity required to accurately predict these interactions using comprehensive rotorcraft analysis tools (e.g., FLIGHTLAB) and validate against wind-tunnel data.

• Provide recommendations for modeling approaches and control strategies to mitigate adverse interaction effects.
  

Methodology

• Conduct a literature review on aerodynamic interferences in multi-rotor and lift-plus-cruise configurations.

• Analyze wind-tunnel data (PIV) of a lift-plus-cruise aircraft to identify characteristic aerodynamic interaction patterns.

• Develop and apply aerodynamic models (or using  already available rotorcraft analysis software like FLIGHTLAB) to simulate the aircraft in transitional speed regimes.

• Investigate the influence of trim control allocation on interaction effects, including potential mitigation strategies.

• Compare modeling predictions against FLIGHTLAB simulations as well as wind-tunnel measurements to assess required fidelity for accurate performance predictions.

Result

• Advancements in the understanding and prediction of the aerodynamic interactions occurring on lift-plus-cruise aircraft configurations in hover, transition and forward flight.

• Insights into optimal trim solutions for lift-plus-cruise aircraft configurations considering trade-offs in performance and flight dynamics.

Duration

Minimum 6 months, starting as soon as possible.

Profile

• Master student Aerospace Engineering, preferably background in aerodynamics

• Experience with rotorcraft modelling & simulation

• Familiarity with wind-tunnel data analysis and rotorcraft flight control is beneficial

• Assertive & self-motivated, able to be part of the project team and also proceed individually

What we offer

• A challenging graduation project in a high-tech result orientated work environment

• Weekly supervision and availability of the technical staff for support

• An internship allowance

• Compensation for double living expenses in case of temporary relocation

• Working in an actual R&D project as part of the team

• Internship results to be used in the current and future projects

About NLR

Royal NLR has been the ambitious research organisation with the will to keep innovating for over 100 years. With that drive, we make the world of transportation safer, more sustainable, more efficient and more effective. We are on the threshold of breakthrough innovations. Plans and ideas start to move when these are fed with the right energy. Over 800 driven professionals work on research and innovation. From aircraft engineers to psychologists and from mathematicians to application experts.

Our colleagues are happy to tell you what it’s like to work at NLR.

This assignment will be managed by the Vertical Flight group within the Aerospace Vehicles Vertical Flight and Aeroacoustics (AVVA) department.

Interested?

Contact us for more information or send your application, together with your motivation letter and CV, to George Tzanetos Alevras at George.Tzanetos.Alevras@nlr.nl and Dr. Furkat Yunus at f.yunus@tudelft.nl and we will contact you as soon as possible.