1. 제 목 : Sound Transmission Through Lined, Composite Fuselage Structures





2. 연 사 : Professor J. Stuart Bolton (School of Mechanical Engineering, Ray W.Herrick Laboratories, Purdue University, USA)





3. 일 시 : 2002년 11월 13일 (수요일) 16:00 - 17:30





4. 장 소 : 서울대 신공학관(301동) 117호 세미나실





5. 내 용 :





A new composite material consisting of carbon-fiber reinforced laminate sheets bonded to a flexible honeycomb core is currently being used as a substitute for rib-stiffened aluminum panels in a business jet fuselage application. The honeycomb sandwich panel is as light as aluminum but it is much thicker and its flexural stiffness is much higher. The transmission loss of the honeycomb panel has been measured an it was found to be significantly less than that of an aluminum panel having the same mass per unit area. To identify the source of this difference, a model for sound transmission through composite panels has been developed. Since the core has different strengths in the in-plane and out-of-plane directions due to its rectangular cell shape it is appropriate to model the core as being transversely isotropic: such a model, based on porous material theory, has been developed. To validate the transversely isotropic model, transmission loss measurements of multi-layered configurations have been compared with predictions, and good agreement has been obtained. By exercising the model, it has been found that the transmission loss of the panel is largely controlled by the core shear stiffness and its associated loss factor. Thus the core stiffness properties must be modified to improve the panel transmission loss. In addition, the transmission loss of the panel and the complete sidewall barrier treatment has been measured and compared with the predictions of the transversely isotropic model: excellent agreement has been found. The measured and predicted results also show that the transmission loss performance of the fuselage could be improved by as much as 10 dB to 15 dB at 3 kHz and above by lining the ¼ in airspace between the honeycomb sandwich panel and the interior trim with high performance glass fiber.





6. 약 력 :





Professor of Mechanical Engineering at Purdue University.


M.Sc. and Ph.D. from the Institute of Sound and Vibration Research at Southampton University in England.


Fellow of the Acoustical Society of America.


Technical Program Chair: NOISE-CON 88, INTER-NOISE 95, NOISE-CON 98,


and the Spring 1996 meeting of the Acoustical Society of America.





7. 문 의 : 기계항공공학부 강연준 교수 (☏ 880-1691)


서울대 BK21 기계분야사업단 행정실 (☏ 880-7132)