The “Honji-Do” temple located in the “Nikko Toshogu” area, in Nikko City, Japan, is famous for its strange acoustic phenomenon called “Roaring Dragon”. A dragon is painted on the ceiling of this building and we can hear a strange fluttering echo when making a handclap under the head of the dragon. The temple was unfortunately destroyed by an accidental fire in 1961 and was rebuilt in 1969. In the reconstruction work, reproduction of the “Roaring Dragon” was one of the most important items and a 1/4 acoustic scale model experiment was performed to study the reason of the acoustic phenomenon and the way of its reconstruction. In this study, numerical analyses using the finite difference time domain (FDTD) method have been performed to examine the “Roaring Dragon” phenomenon by referring the results of the scale model experiment. Furthermore, the acoustic phenomenon has been simulated in an anechoic room by applying a 3-D sound field simulation technique.
