Ultrasonic diffraction by a circular transducer: Isogeometric analysis sensitivity to full Gauss quadrature points

A successful evaluation of a radiated acoustic field was obtained by discretizing a circular transducer surface into only 20 Bézier elements. Accuracy of results was highly dependent on the number of Gauss points (ngp) used. This number can lead to changing the amplitude of both plane and edge waves, especially for near field points. But most changes have been detected between those waves where unexpected waves appeared. They can be of the same amplitude as the plane wave if ngp is chosen arbitrarily. To improve accuracy, the ngp must be increased gradually from the transducer centre and not only at its edge.