Study of periodic turbulent pipe flow

Technical Report · Fri Jan 01 04:00:00 EST 1982

OSTI ID:6007633

Ramaprian, B R; Tu, S W

Oscillatory turbulent flow in a 50 mm diameter pipe at an average velocity of 1 m/s was studied experimentally and numerically. Instantaneous velocity and wall shear stress were measured using a frequency shifted laser Doppler anemometer and a flush mounted hot film surface gage. The data obtained include turbulent intensities, Reynolds shear stress, energy spectra and autocorrelations. Two oscillation frequencies, (0.5 Hz and 3.6 Hz) were studied. The higher frequency is of the order of the turbulent bursting frequency in the flow. The lower frequency can be considered to be an intermediate' frequency. At the high frequency, the time mean properties are found to be affected by the imposed oscillation. At 0.5 Hz, these properties are not significantly affected. The turbulent structure of the flow, however, is significantly affected at both the frequencies and is considerably different from that in quasisteady flow. Based on this study, it is possible to classify unsteady flows into five different regimes. The validity of quasisteady' turbulence modeling in the prediction of these flows is examined with reference to each of these regimes.

• Research Organization: Iowa Univ., Iowa City (USA)
• OSTI ID: 6007633
• Report Number(s): N-8233680; PB-82-201534; IIHR-238
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
ENERGY SPECTRA
FLUID FLOW
MATHEMATICS
MECHANICAL PROPERTIES
NUMERICAL ANALYSIS
SHEAR PROPERTIES
SPECTRA
TURBULENT FLOW
UNSTEADY FLOW