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The thermal inertia of aircraft cabins and galleys is significant for commercial aircraft. The aircraft cabin is controlled by the Environment Control System (ECS) to reach, among other targets, a prescribed temperature. By allowing a temperature band of ± 2 K instead of a fixed temperature, it is possible to use this thermal dynamic of the cabin as energy storage. This storage can then be used to reduce electrical peak power, increase efficiency of the ECS, reduce thermal cooling peak power, or reduce engine offtake if it is costly or not sufficiently available. In the same way, also the aircraft galleys can be exploited. Since ECS and galleys are among the largest consumers of electrical power or bleed air, there is a large potential on improving energy efficiency or reducing system mass to reduce fuel consumption of aircraft. This paper investigates different exploitation strategies of cabin and galley dynamics using modelling and simulation.

Advanced modeling and simulation techniques are becoming more important in today's industrial design processes and for aircraft energy systems in specific. They enable early and integrated design as well as validation of finalized system and component designs. This paper describes the main methods and tools that can be applied for different phases of the energy design process. For demonstration, the object-oriented modeling language Modelica was chosen, since it enables convenient modeling of multi-physical systems. Based on this standard, common modeling guidelines, a modeling library template, and common interfaces have been provided. A common modeling infrastructure is proposed with considerations on additional libraries needed for local tasks in the energy design process. The developed methods and tools have been tested by means of some predefined use cases, which are performed in cooperation with diverse aircraft industrial partners.

This paper describes a novel Thermal Management Function (TMF) and its design process developed in the framework of the Clean Sky project. This TMF is capable of calculating optimized control signals in real-time for thermal management systems by using model-based system knowledge. This can be either a physical model of the system or a data record generated from this model. The TMF provides control signals to the air and vapor cycle which are possible sources of cooling power, as well as load reduction or shedding signals. To determine an optimal cooling split between air cycle, vapor cycle, and its associated ram air channels, trade factors are being used to make electrical power offtake and ram air usage (i.e. drag) comparable, since both have influence on fuel consumption. An associated development process is being elaborated that enables a fast adaptation of the TMF to new architectures and systems. This will be illustrated by means of a bleedless thermal management architecture.

Aiming at the global energy optimization of aircraft, the More Electric Aircraft (MEA) concept becomes more interesting for the aeronautical industry. The MEA concept is based on utilizing electric power to drive aircraft subsystems that historically have been driven by a combination of hydraulic, electric, pneumatic and mechanical power transfer systems. The development of the future MEA systems is a challenging task: the system integration is becoming a central topic. In all phases of the system development process, the respective subsystems within the MEA will be treated in a highly integrated manner to achieve optimum efficiency and performance at aircraft and systems level. Concerning the electric network in the future MEA, advanced design and analysis methods based on mathematical models are required to face the potential issues accompanying the MEA. For this purpose, the use of advanced modelling and simulation technologies is a key success factor.

Demonstrators and research projects about electric aircraft taxi systems testify the current interest in low- or zero-emission ground propulsion technologies to lower the overall fuel consumption and emissions of commercial flights. Electric motors fitted in the main landing gears are one of the most promising layouts for these systems especially for narrow-body commercial aircraft. From a control theory point of view, the aircraft on ground becomes an over-actuated plant through adoption of this technology, i.e. a commanded ground trajectory can be reached through different combinations of actuator efforts. A strategy is required to choose the most suitable of these combinations in order to reach the best efficiency. This work aims to investigate a strategy for an optimal control allocation during path-following of prescribed ground trajectories.