A correlation technique using pseudo-random binary-sequence pressure-pulse testing is used to measure reflection coefficients of sharp edged orifices at the end of a duct. Within the range of the incident pressure-wave amplitude investigated in this paper it is believed that no other experimental means has yet been devised. A simple formula is derived from one-dimensional flow theory which gives values showing close agreement with the experimental results. End conditions for non-reflection are established to create an analogy to the hypothetical ‘infinite pipe’.
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