To improve the accuracy of time-varying pressure measurements, many national metrology institutes are developing primary standards for dynamic calibration of pressure sensors. Among these, the most established are the shock tube and the drop-weight liquid system. Although drop-weight liquid systems can generate significantly larger pressure changes than shock tubes, shock tubes allow for a much wider frequency range of calibration. In this master's thesis, we developed and analysed a measurement system with a dynamic pressure generator that combines the advantages of the shock tube and the drop-weight liquid system. The dynamic pressure generator was developed based on an existing diaphragmless shock tube, which generates known pressure steps acting on a piston mounted at the end wall of the driven section. The piston, in turn, acts on the liquid inside a chamber and thereby generates pressure variations on the pressure sensor being calibrated. The newly developed piston dynamic pressure generator was dimensioned using the results of a developed physical–mathematical model. From the measured time-varying generated pressures we determined the amplitude–frequency spectra of the generated pressure and compared them with the theoretical spectra obtained with the model. Experiments confirmed that the usable frequency range of the developed generator extends up to 400 kHz, and its amplitude range reaches up to 234 MPa.
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