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MOTIVE Project Q&A with Liebherr Engineer Julien Daumas

Wed, 27 October, 2021

The MOTIVE project is working on solutions to reduce the incidents of aero-engine bleed valve malfunction. The project is a collaboration between TWI, Scitek, Ventil, ESI and project topic manager, Liebherr.

We took some time to reach out to Liebherr Aeronautical Engineer, Julien Daumas to find out more…

Julien, could you please start by letting us know a little more about the work of Liebherr and your own role at the company?

Liebherr Aerospace Toulouse design, manufacture and sell Integrated Air Management Systems for its aeronautic customers. The systems developed by Liebherr Aerospace Toulouse are :

  • Bleed Air System (BAS)
  • Environmental Control System (ECS)
  • Wing Anti Ice System (WAIS)
  • Cabin Pressure Control System (CPCS)
  • Fuel Tank Inerting System (FTIS)
  • Avionics Cooling System (ACS)
  • Air Quality System (AQS)
  • Vapor Cycle System (VCS)

Liebherr Aerospace Toulouse systems are composed of several components:

To develop its systems and components, Liebherr Aerospace Toulouse massively use modelling and simulation:

  • Model Based System Engineering
  • Model Based Analysis (Physical Simulations)
  • Model Based Manufacturing
  • Model Based Design
  • Model Based Support

I work in the Scientific Tools team in charge of the development of internal tools needed by the business to design Liebherr Aerospace Toulouse systems and components. In this team, I’m in charge of R&T and CfP project management, digital continuity between the analysis tools and the other models and consistency of the Model Based Analysis strategy.

Can you let us know a little bit about aero-engine bleed air systems – what they do and why they are important?

The conventional bleed air system has four high level functions:

  • To provide pressured air to others consumer systems (all the other systems of the IAMS)
  • To select the engine port from which the pressured air is taken
  • To regulate the pressure of the air flow available at the output of the system
  • To regulate the temperature of the air flow available at the output of the system

What are the challenges with these systems, which the MOTIVE project is trying to address?

The new aircraft engines submit Bleed Air Systems to harder environments in terms of temperature and available volume for integration. These harder environments have a physical effect on the bleed components that have to be modelled to simulate the bleed air system dynamic behaviour for the more green aircraft engines.

The challenge of MOTIVE is to provide data and models needed to improve the Bleed Air System behaviour modelling.

What are the solutions that the project is seeking to implement and how are Liebherr involved in particular?

As topic manager, Liebherr Aerospace Toulouse:

  • defines the scope of the project
  • provides input data needed to develop models
  • shares knowledge on Bleed Air System
  • defines the technical needs

From these topics, and to improve the simulation of the bleed dynamic behaviour, the project has to develop physical 1D models of:

  • sealing rings friction depending of physical and design parameters
  • butterfly aerodynamic torque depending of design parameters
  • diaphragm mechanical behavior depending of physical and design parameters


The MOTIVE project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 785530