Modelling of buoyancy control for new generation aircraft

Aircraft research is in a state of transition, with a much broader range of possible new aircraft technologies under investigation than ever before. New technologies include boundary layer ingestion, hydrogen fuelled aircraft, electrically powered aircraft and distributed propulsion schemes [IATA Technology Roadmap to 2050 (2019)]. Most of these are driven by the imperative to reduce carbon emissions in order to reduce, and indeed reverse, the growth of the carbon footprint produced by the increasing number of air miles flown each year [IATA 20 year passenger forecast (2019)].

This imperative has reinvigorated the notion of the use of ballonets to produce lift in aircraft, primarily in assisting craft to reach their cruising altitude, and considerable research interest in this area has been generated [Zhu et al (2021), Wang et al (2021)]. It is estimated that up to 20% of the total fuel consumption for a short-haul flight is consumed in reaching the required cruising altitude alone [see, for instance, the Quora reference below], and at the moment the energy content of the fuel is completely lost. This project proposes to investigate the use of ballonets to assist in fuel reduction by production of buoyant lift, by modelling a range of possible configurations and the use of a mix of potential gases. A number of possible configurations will be investigated, such as the use of fixed or inflatable elements, along with potential energy recovery in descent by re-pressurisation of the buoyant gases.

This project will require a sound understanding of physical principles, especially those relating to flight and buoyancy, as well as good modelling skills, It would particularly suit a graduate in Physics, Aerospace or Aeronautical Engineering, or an equivalent area. Detailed background knowledge in this area is not required, but enthusiasm, flexibility and a drive to make progress are essential.