Sample Thesis Paper
– The equipments were connected as described above and then turned on.
– The Wavetek generator was set to produce the electrical signal to the transducer.
– The oscilloscope was set to display two traces, one for the transmitted pulse, and one for the received pulse.
– The hydrophone was placed by the eye on the axis of symmetry of the transducer, about 10 mm away from the face of transducer. The error in this step is estimated to be ± 2 mm in both directions, longitudinal and lateral. The signal received by the hydrophone was adjusted until it was clearly observable on the oscilloscope. The temperature of the water was recorded at 22 Co.
– The amplitude of the acoustic signal was recorded and then the hydrophone displaced along the longitudinal direction, by 1 ± 0.1 mm from the transducer. After 14 readings, the displacement was increased to 2 ± 0.1 mm. Consequently, the time delay between the transmitted signal and the received one was recorded at every 10 mm displacement from the transducer.
As result, the data of the acoustic signal amplitude, which was collected along the axis of symmetry of the transducer, represents the waveform of the longitudinal axis, see Table 1 [Appendix 1]. For the data of the time delay of the received signal, see Table 2 [Appendix 1].
At two chosen points (12 mm, 106 mm) of the transducer longitudinal axis, the acoustic field amplitude on the lateral axis were recorded. This illustrates the waveform of the lateral axis of the transmitted signal; see Table 3 and Table 4 [Appendix 1].