MTU Aero Clean Sky 2 Demonstrators

As a participant in the European research initiative Clean Sky 2, MTU Aero Engines is advancing its component technology, focusing on the low-pressure turbine (LPT) and high-pressure compressor (HPC), and constructing two demonstration models. The Engine Material Validation (EMVAL) engine demonstrator is under construction in Munich, intended to validate LPT technologies. Concurrently, a dual-shaft compressor rig for new compressor technologies is being assembled, with tests to be conducted at the German Aerospace Center (DLR) in Cologne.

MTU's Clean Sky 2 endeavor aims to "concentrate on how our components interact with their neighboring parts, and we especially want to optimize that interaction," said Dr. Claus Riegler, Senior Vice President of Technology & Engineering Advanced Programs at MTU. This optimization involves the inlet and exit case for the low-pressure turbines, while the low-pressure compressor and the transition duct significantly influence the high-pressure compressor. The overall objective includes enhancing aerodynamics and developing new, lighter, and more temperature-resistant materials.

Caption: 3d rendering of the dual-shaft compressor rig. Credit: MTU Aero Engines.

The EMVAL engine demonstrator, an MTR390 model, is being retrofitted in Munich. "This summer we will be able to run EMVAL at our test cell for the first time," said Michael Schall, Senior Manager of Technology Demonstrator and Rigs. “The analysis of material behavior under engine conditions will then provide proof that the technologies are mature."

This includes design modifications, advanced heat-resistant materials like fiber ceramics and monocrystals, disk materials, and additively manufactured components. GKN Aerospace is supplying the turbine exhaust case.

Simultaneously, a dual-shaft compressor rig is in the works at MTU in Munich to augment the compressor system. The rig also includes the inter-compressor duct (ICD).

"Our goal is to create even better coordination between the low-pressure compressor, ICD, and high-pressure compressor in order to leverage new potential for even more fuel-efficient engines," Riegler said. A crucial aspect is the systematic measurement of flow conditions in short, steep ICDs.

Testing of the dual-shaft rig is expected to begin at the DLR in autumn, with completion and evaluation set for next year. These validated technologies will contribute to future geared turbofan engines. GKN Aerospace is collaborating with MTU, with the Swedish engine specialists responsible for the design and manufacturing of the low-pressure compressor and the transition duct.