Turbomachinery and Propulsion

The ADA (Aggressive Duct Aerodynamics) project is a project coordinated by GKN Aerospace Sweden AB, carried out in collaboration with KTH. The project is implemented through two technical work packages led by GKN (WP1) and KTH (WP2) respectively. WP1 aims to understand the detailed flow in aerodynamically aggressive intermediate compressor ducts and to establish the most effective methods to predict these flows, while WP2 aims to investigate the most effective methods to extend the aerodynamic duty of such ducts by using passive and active flow control devices. ADA is intended to run in parallel to, and collaborate with, the German LuFo project RDUCT where experimental research will be done on active and passive flow control in intermediate compressor ducts by TU-Berlin and DLR in Germany. Experimental data from RDUCT will be shared with ADA.

The project aims at obtaining experimental data to verify and improve accuracy in aerodynamic damping and flutter predictions for the conditions where available calculation methods are not fully validated or reliable. In particular, the focus will be on aeroelastic response of the compressor blades vibrating in a near stall flow condition.

The main overall objective is systematically experimentally quantify the coupled resonance occurring due to interaction between vortex oscillations from the boundary layer / shear layer flow passing over a cavity and the acoustic cavity. This targeted to provide validation data for in-house acoustic codes at industry in order to strengthen design prediction capabilities.

Turbomachinery in its various applications form the principal prime mover in the energy and aviation industries. Any improvement to this vast fleet of machines has the potential of significant impact on global emissions. Areas identified to benefit from continued research are the topics of flow mixing and cooling.
These are topics inherent in stationary gas turbines and jet engines due to the hot gas flows utilized. Cooling is achieved through injection of cold air in critical areas and thereby ensuring safe operation. The cooling however comes at a cost. On the cycle level this flow requires power to be compressed to the appropriate pressure, but does not contribute to the cycle output. In addition, the injection itself reduces the output power due to the losses associated with the mixing process. The study is centered to a turbine testing facility allowing detailed flow measurements in a rotating turbine stage under the influence of the cavity purge flow and also develop CFD models which can simulate the flow physics accurately.

The project focuses on aerodynamic and aeromechanical evaluation and detection of degraded and damaged fan- and compressor blades, as well as repair actions, in modern aero engines. The project is coordinated by GKN Aerospace AB and continues an established collaboration between GKN, KTH and Stuttgart University, Germany. The collaboration with Stuttgart University allows Swedish partners access to advanced European experimental infrastructure in aerospace engineering which does not exist in Sweden.

Due to the need to decarbonize the heating sector, alternative pathways of producing heat are needed where large heat pumps (HP) can play an important role. To make optimal HP designs with high performance and wide operating range there is a need for a compressor test platform to ensure research advancements. The project will strengthen the already ongoing, related energy research at the department of Energy Technology KTH. Several EU and national funded projects are studying novel concepts concerning heat pump cycles and their key components. Exploration and utilization are ensured with a broad representation from industry and academia within the project group.

For future rocket propulsion systems it is of strategic importance to develop knowledge of the heat transfer characteristics and material influence at relevant operating conditions. This project will investigate, for different relevant nickel-alloys and typical channel geometries, hydrocarbon fuels and operating conditions to determine: heat transfer coefficient (HTC), degree of coking and corrosion in the cooling channel, pressure loss as a function of supplied heat load, wall temperature, Reynolds number, fuel composition and pressure level.

For future rocket propulsion systems it is of strategic importance to develop knowledge of the heat transfer characteristics and material influence at relevant operating conditions. This project will investigate, for different relevant nickel-alloys and typical channel geometries, hydrocarbon fuels and operating conditions to determine: heat transfer coefficient (HTC), degree of coking and corrosion in the cooling channel, pressure loss as a function of supplied heat load, wall temperature, Reynolds number, fuel composition and pressure level.

Additive manufacturing (AM) as a production method for components is becoming increasingly promising around the world, this project looks at the use of AM components in the space industry, particularly in propulsion technology. With all major space agencies moving towards reusable space launchers, this process comes in handy as very complex shapes can be manufactured with relative ease and with shorter lead times, however the inherent surface roughness of the components produced using this method poses a challenge to the widespread usability of this method as designing efficient turbomachinery for the rocket launchers would require us to understand the effect of surface roughness on the performance of these turbomachines. The study of this critical phenomena is a vital step to certify this manufacturing process for the space industry which has stringent safety requirements for components.

This project continues the development of a future engine concept where focus is on increased electrification, engine weight reduction and overall noise reduction. The impact of new technologies on the aircraft engine architecture is studied and quantified to better understand the associated challenges. The virtual platform that will be developed further in the project has previously been shown to promote technical collaboration, research and information exchange between academia and industry in Sweden. The project will facilitate the development of methods for aircraft engine component designs targeting improved engine performance and increased overall efficiency.