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The purpose of this paper is to determine thermal behaviour of wing fuel tank wall via heating by external heat sources.

A 3D finite element model of the structure has been created that takes into account convection, conduction and radiation effects. In addition, a 3D finite volume model of the air inside the leading edge is created. Through a computational fluid dynamics approach, the flow of air and thermal behaviour of the air is modelled. The structure and fluid model are coupled via a co-simulation engine to exchange heat flux and temperature. Different ventilation cases of the leading edge and their impact on the thermal behaviour of the tank wall (corresponding to the front spar) are investigated.

Results of 3D analysis illustrate good insight into the thermal behaviour of the tank wall. Furthermore, if regions exist in the leading edge that differs significantly from the overall thermal picture of the leading edge, these are visible in a 3D analysis. Finally, the models can be used to support a flammability analysis assessment.

Provided that the bleed pipe is located far enough from the spar and covered with sufficient thermal heat isolation, the composite leading edge structure will not reach extremely high temperatures.

These detailed simulations provide accurate results which can be used as reliable input for the fuel tank flammability analysis.

The rest-to-rest movements for a spacecraft, such as attitude adjustment and orbital manoeuver, are likely to excite residual vibration of flexible appendages, which may affect the attitude accuracy and even result in severe structural damage. The purpose of this paper is to present an approach to attenuating the vibration of flexible solar array by using reaction flywheel.

The reaction flywheel installed on solar array served as an actuator to provide reaction torque to a structure according to a designed feedback control law. This torque can be considered as an artificial damping. Experiment on a scale model of the solar array is first performed to verify the effectiveness of this method. Numerical simulation on finite element model of a full-scale solar array is subsequently carried out to confirm the validity of this method for practical engineering application.

The vibration suppression effect on the structure using a reaction flywheel is deduced by theoretical analysis. Results from both experiment and numerical simulation reveal that the efficiency of vibration attenuation is promoted.

Improvements on control law are left for further study. Additionally, only the first-order bending vibration of the flexible solar array is attenuated, and further study is required for other types of vibration suppression.

An effective method is proposed for spacecraft designers to actively suppress the vibration of the flexible solar array.

A novel active vibration reduction scheme is proposed using a reaction flywheel to suppress vibration of the flexible solar array. This paper fulfils a source of theoretical analysis and experimental studies for vibration reduction measure design and provides practical help for the spacecraft designers.