Pulsating turbulent flow in a tube was studied experimentally. Measured instantaneous profiles of the velocity and the intensity of turbulence can be clearly classified into two groups by means of a certain critical period of pulsation. At longer periods of pulsation, the shapes of the velocity profiles are similar to those for steady flow, while the intensity of turbulent fluctuation does not pulsate ; whereas at shorter periods, the velocity profiles are not similar to those for steady flow, while the intensity of turbulent fluctuation pulsates oppositely to the velocity.
From measuring the time intervals between bursts in both steady and pulsating turbulent flows, it was clarified that the range of burst periods occurring in pulsating flow was the same as the preferred range of burst periods in steady flow. If the pulsation period is longer than the upper limit of this range, the mean burst period is equal to that of steady flow, but if the pulsation period is included in the range of burst periods for steady flow, the bursting of the same period as the pulsation period dominates.