Pressure, absolute piezoelectric

It is notoriously difficult to get reliable pressure measurements with piezoelectric transducers in a detonation experiment, and the failure to obtain agreement between the absolute measured pressure and predictions is not very surprising. This discrepancy appears to be partially removed by comparing relative values (ratios) rather than absolute pressures. Note that the overall features of the experimental pressure histories are in agreement with the computations, but high levels of pressure oscillations (5-20%) are observed, whereas the numerical simulations produce very smooth results. 

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