A pressure pulsation phenomenon in positive displacement machinery and resulting from that noise and vibration problems are well-known and still unsolved issues. The article concerns modeling pressure pulsation dampers used for fluid machinery, in particular in gas systems. The currently used mathematical models based on the plane wave theory are verified in the special laboratory conditions with no flow and no wave reflections at the system outlet. The use of a compressor as an excitation source significantly influences the characteristics of a damper installed in a system. In this study, a measurement of common type dampers transmission loss characteristics with the use of pressure transducers is proposed. The article discusses the influence of boundary conditions in analytical models based on the plane wave theory on the accuracy of dampers characteristics. Basing on the measurements results some improvements in the analytical model are proposed.

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The article presents the results of experiments aimed at finding the displacement of a cylinder being part of a boom system, as recorded after initiating a rapid breaking process. The tests were performed on a special test stand which allows modifications of the control system architecture. The article presents a comparative analysis of three systems different with respect to their architecture and use of control valves. It discusses the test results and the influence of the architecture of a hydrostatic system on the accuracy of the resultant position of the working element. The article also describes the influence of external loads on the working movement accuracy of the tested systems. The results allow the author to relate the structure of a hydraulic system to the parameter of the obtained working movement accuracy with respect to the maximum values of pressures and dynamic forces.