Experimental Investigation of the Time Effect of Pressure Fluctuations in Steady Turbulent Pipe Flows

Abstract

In the study, which performed experimentally, the behavior of time variation of the static pressure in pipe water flows has been investigated in terms of pipe diameter, flow rate and pipe roughness. In the experiments, five pipe types in different materials and in different roughness were used. In the steady and horizontal pipe water flows, which performed at low Reynolds numbers, the static pressure at different tap locations which is longitudinally placed have been measured. The water heights in the piezometer hoses, which is inserted on pressure taps, has been recorded with a camera for three minutes for each flow rates. A total of 21 snapshots were obtained from each camera recordings at equal time intervals and the pressures were determined from that snapshot images through water height readings. The sanpshots of any flow rate has shown that all pressures at the tap locations fluctuate together over the time in the same phase, frequency and amplitude. When RMS values, which shows the pressure fluctuation in mean intensity over the time, was examined, it was observed that the fluctuation amplitudes is independent of pipe roughness but has a relation with velocity of the pipe flow.

Keywords

• Pipe flows,Pressure fluctuations

References

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