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

Yıl 2018, Sayı: 2, 90 - 100, 19.08.2018

Hasan Duz Ahmet Beyzade Demırpolat

Öz

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.

Anahtar Kelimeler

Pipe flows, Pressure fluctuations

Kaynakça

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