In the matching work, the object to be considered is the difference between the calculation and the measurement about the octave band whose center frequency is 1 kHz, which is seemed to be large part of the noise in the ship. The data measured at the passage or the stairway is not reliable because other noise such as the noise generated at the walking exists. Also the data measured at the wall except for the steel is not reliable because the accuracy of the parameter used at the conversion to STL is not reliable. These data has been omitted in the matching work.
5.2.3 Estimated Results and Discussions of The Ship Concerned (ShipNo.1)
Values obtained through the procedure described in 5.2.2 were used for the parameters in the calculation of the noise prediction of the ship concerned. The procedure of the comparison is as same as the one described in 5.2.2. The 48 data of the air borne noise for the rooms and the 57 data of the structure borne noise for the walls were selected from the 1118 elements which compose the calculation model for the comparison. The results of the calculation and the measurement about the octave band of 1 kHZ center frequency are shown in Table 3, and the reference points of these data are shown in Figure 4, respectively. Figure 5 shows the differences between the calculation and the measurement about these points in the form of the histogram. It can be seen from these data that differences between the calculation and the measurement are almost within the proper range except the several structure borne data whose differences is over 10dB. The energy flow of the steel plate which has the vertical continuity through the decks in the accommodation space and is used as the strength member is very interesting data.
