기하음향 기법을 적용한 한국형 고속철도 실내소음 저감 방안

Abstract

The interior sound pressure level of the Korean high-speed train(KHST) is predicted by geometrical acoustic method. For the purpose of assuring the prediction of interior noise of KHST by the geometrical acoustic scheme, calculated sound level values of the Korean train express(KTX) by identical geometrical method are compared with measured values of KTX prototype vehicle by experiment. Contribution of individual sound source of KHST vehicle into the interior response positions is calculated and sound sources are classified in influential order. Hence, it is reasonable approach to reduce sound power of most contributing noise source first. Sensitivity of the interior response position's sound pressure level(SPL) with respect to train wall sections' transmission loss are carried on and acoustically sensitive spot is identified, for example window area for passenger cabin case. Those contribution and sensitivity analysis results are suggested to design quieter train efficiently.