Objectives

The main goal of the project is to define a holistic approach (both experimental and numerical) to quantify the energy-dissipation effects associated with the liquid movement inside aircraft fuel tanks, as the wing undergoes dynamic excitations. A substantive (in the order of 50%) increase in the damping characteristics of the structure is expected.

The SLOWD consortium partners bring together industrial know-how and academic research, with the following objectives:

a) Setup of an Experimental Campaign to investigate the response to dynamic loading of the wings of a modern passenger airliner (200 passengers or more) carrying fuel. The results of the campaign would be a database of measurements for benchmarking the numerical and analytical methods developed during the remainder of the project. The measured quantities will include time-varying parameters (e.g. accelerations, displacements, wall pressures) from which the damping effect of the slosh will be computed.
b) Further Develop Numerical Methods, for the concurrent modelling of the experimental setup.

The aim of the modelling is twofold; preliminary calculations will be undertaken to inform the design of the experimental campaign. Subsequently, a high-fidelity digital-twin of the experimental set-up will be generated, which will provide a wealth of data from which reduced order models can be built. The numerical methods are to be implemented in executable software and made available to all partners on a common computing environment for purposes of the project.

c) Evaluate Reduced-Order and Analytical Models, as reduction in the complexity of the numerical models is deemed necessary for subsequent inclusion into an industrial design framework. Several reduced-order and analytical models will be evaluated in terms of their computation efficiency and accuracy in predicting sloshing-related dissipative effects. As per the numerical methods, the methods for deriving ROMs are to be implemented in executable software and made available to the partners on a common computing environment for the purposes of the project.

d) Integration of the Models into a Multidisciplinary Design Framework. An industrialised version of the software developed in b) and c) will be used to understand the influence of design parameters such as baffle spacing, baffle openings, fill-level to define an optimal architecture of the wing fuel tanks, which maximises the dissipation effects due to fuel sloshing.

The SLOWD consortium intends to liaise with airworthiness authorities for future inclusion of the tests (or some of their elements) in the certification regulations for large airplanes (CS25) so to provide a safe and more specific acceptable means of compliance for the aeronautical industries operating in the European Union.