Testerman and McLeod [39] designed and built a detector based on the whistle principle. In their sensor design, typical values taken for the dimensions in the diagram, and variables in the equation, were (t), 0.064 mm, (d), 0.74 mm, (h), 1.676 mm and (L) 3.81 mm.
Figure 59 The Supersonic Whistle Detector Sensor
