Press Release

S & C Thermofluids is proud to announce the design and development of a new test rig to investigate the plume trajectory of a thrust reverser system during landing.

The rig contains:

• a half symmetry model of a nose to tail fuselage and wing
• a simulated engine producing the thrust reverser and small axial core flows
• a flight stream covering the entire model at a proportional landing speed
• a rolling road system to simulate the runway

The rig was developed under SANTANA: System Advances in Nacelle Technology AerodyNAmics, an ATI R&T Programme funded project. Led by Bombardier Belfast, the SANTANA project was a collaborative programme focused on the development of aerodynamic technologies related to the design of advanced ultra-high bypass ratio powerplant nacelles. The programme was completed in December 2016 and targeted nacelle components for next generation aircraft. Within the project there was a requirement to investigate providing experimental data of the trajectory of a thrust reverser plume in the landing phase, to compare against a full scale CFD model.

The most ambitious development was a means of providing the core flow at small scale. In the end an existing AMT Olympus model engine was modified to act as an air mover - so the combustion components were removed, and the blades were turned using a small compressed air supply which in turn drew ambient air through the intake. The back end was then replaced with a 3D printed section which was designed to replicate the exit trajectories of a fully deployed thrust reverser. The intention is to allow these rear end sections to be readily replaced to provide comparable data for designs with different exit angles.

The aircraft geometry is a combination of aluminium and 3D printed sections which provided significant cost and delivery benefits to the project. The framework supporting these components could be adapted to allow future testing with different aircraft models.

The flight stream is provided by S & C's large scale Flight Stream 2 rig. This is driven by two Gnome turboshaft rigs supplying compressed air to ejectors, which entrain large volumes of ambient air into a settling chamber. The working section was designed to supply a flight stream of 10-12m/s, to provide the same momentum balance ratio between the flight stream and thrust reverser flow as found at full scale.

The results can be provided as both qualitative and quantitative data. S & C Thermofluids operates a full pressure and temperature logging system and this was used to monitor the flow conditions in and around the simulated engine, and to investigate the locations where the plume impinged on the fuselage. Additionally, infrared imagery provided thermal data for the surfaces. Visualisation techniques included smoke, water mist and thin strings.

The results from the initial commissioning runs were very encouraging. The thrust reverser plume and the flight stream could be independently controlled to replicate the interaction between the two opposing flows. The pressure tappings on the fuselage were also demonstrating a trend relating to the impingement locations at different flight speeds and engine power.

Tony Smith, Director of S & C Thermofluids, says "The plume trajectory rig has proved a significant development to the company's test capabilities. It demonstrates the operation of multiple flows simultaneously, providing a full system test. We are excited at the potential developments of this rig and have already been discussing ways of integrating a full combusting engine into the landing environment. This would greatly improve the infrared results and would allow us to investigate thermal mixing of the plume with the flight stream. We would also like to instrument more locations on the aircraft to build a complete picture of the impact of the thrust reverser on the body. We look forward to exploiting this capability within the aerospace community."

About ATI R&T Programme

The project is receiving funding from the aerospace R&D programme, a £3.9 billion joint funding commitment from industry and government to support projects which build on the UK’s strengths and develop the products and manufacturing technologies that will best position the UK to sustain its global competitiveness. The programme is delivered in partnership between the Department for Business, Innovation and Skills, Innovate UK, and the Aerospace Technology Institute. The commitment was made in 2013 and the 2015 Spending Review announced that the funding would be extended by 6 years to 2025 to 2026, worth an additional £900 million from the government.