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Download or read book Performance Improvement of Embedded Electric Actuators by Means of a Thermal Management Optimisation written by Francesco De Giorgi and published by . This book was released on 2021 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal management issue is one of the remaining barriers to the use of electrical actuators for primary flight control applications, as their performance and especially their reliability is highly dependent on the operating temperature. Until now, hydraulic technologies have allowed excess heat to be evacuated through the hydraulic network. The problem was relocated and heat exchangers were used to cool the hydraulic fluid. The increasing electrification of aircraft pushes toward the suppression of the hydraulic network and, as a result, the hydraulic fluid will not be available as a convenient means of transporting and dissipating the heat generated by the actuators. New thermal management solutions for dealing with the component heat load at a local level are needed. Several studies have looked specifically to this purpose, which provided efficient potential solutions for the thermal management of electrical flight actuators. This thesis mainly focuses on a topic that has not yet been fully explored in the literature, which concerns the optimal design and coupling of such solutions with the actuator system. In fact, if these solutions are optimally integrated during the preliminary design phase of the actuator, they can provide not only an improvement in the performance of the actuation system, but also the development of a lighter and more compact system, leading to considerable advantages at aircraft level. The objective of this thesis is to provide effective methods and tools suited for the preliminary design of electrical actuators, with a particular attention to the thermal management. The first part of the thesis concerns the identification of potential thermal management solutions. Thermal management systems such as plate fin heat exchanger, heat pipes, thermal straps and phase change materials are investigated. The second part of the thesis regards the implementation of a procedure to optimally preliminary design the coupled system composed by the actuator and its associated thermal management device. Firstly, estimation models are generated in order to estimate the dimensions and performance of cooling devices and actuator components. To this purpose, a new methodology for obtaining simpler and lighter surrogate models is proposed. Subsequently the preliminary design procedure is defined via a Multidisciplinary System Design Optimization with a view focused on the mass minimization and thermal constraints satisfaction. Two different approaches for sizing the actuation system are proposed. The first approach consists of performing the preliminary design on the basis of static specifications extrapolated from the mission profile. This approach allows a rapid estimation of the actuator dimensions and performance, but does not guarantee optimal thermal dynamics over the entire flight duration. The second approach, more expensive from a computational point of view, consists in integrating the mission profile in the preliminary design, thus allowing the realisation of a system which ensures an optimal thermal dynamic along the mission profile. Based on the case study of an Airbus A320 and referring to an electro-mechanical actuator, the proposed approaches are applied here to conduct the preliminary design for the whole set of primary flight control surfaces: Aileron, Rudder and Elevator. A quantitative comparison of the most suitable thermal management concepts is made for each of these applications.