From engine integration to cabin noise: drivers to accurate interior noise evaluations
The present paper addresses the topic of of end-to-end cabin noise aero-vibro-acoustic prediction for civil aircraft. Through an overview of Airbus cabin noise prediction means and related investigations, the sensitivity of cabin noise to key parameters at engine and aircraft levels is demonstrated, highlighting the need for high fidelity numerical and experimental capabilities as well as integrated ways of working between engine and aircraft manufactureres in the frame of engine design to cabin noise.
Design Requirements of Acoustic Flight LAB Platform
Economic aircraft design demands for short development times. In frame of interior noise this requires reliable prediction methods for the design process, where the complex interaction of the excitation/fuselage as well as the radiation to the cabin is captured. Especially in the mid frequency range between 80-250Hz modern finite element based numerical models still show a lack of accuracy for a full aircraft configuration. However it is difficult to find out which part of the model has the highest impact on accuracy. Flight tests/ground tests of full aircraft configurations have an inherent high complexity and only a limited observability. Therefore in frame of the Lufo-4 funded project COCLEA an acoustic design platform is developed to serve as basis to improve numerical models by stepwise increase of the complexity. The main design requirements are: realistic excitation, fuselage structure with low complexity and clean boundary conditions. In this paper the importance of these requirements are demonstrated by results from an existing platform (A400M Fuselage Demonstrator). Here the limits due to high complexity and boundary conditions are shown by comparison of numerical model with detailed test data. Furthermore first results of the excitation reproduction system consisting out of 128 speaker array are presented.
Simulating the Illuminance and Efficiency of the LEDs Used in General Household Lighting
Abstract The advantage of the LEDs illumination in general household lighting was proposed. High efficiency white LED as the light source was provided the energy saving illumination of the general household lightings. Different spaces in general household with different standards of average illuminance were designed and simulated by LightTools and DIALux software. The power consumptions and efficiency of traditional illuminated light sources and LED light source in lighting the household environment were analyzed and compared with each other at the same standard of average illuminance. Finally, it provided the advantage of using white LEDs in different spaces of the general household lighting.