| Abstract: | ![]()
In [1, 2], as a result of measurements of the hydraulic resistance and the friction in vertical tubes, a region of the flow with anomalously high values of these quantities was disclosed. The measured values of the resistance exceed by an order of magnitude values obtained using appropriate calculating methods. This region of the flow corresponds to bubble-type flow conditions with small reduced velocities of the liquid phase. The above communications do not give a clear explanation of the observed effect. The calculating method proposed in [2], which pretends to take this effect into consideration, does not describe the experimental results of other authors, for example, the results of [1]. In the present work the limits of the existence of this set of conditions were established, and the mean and pulsational characteristics of the friction were measured. It is shown that this region of anomalously high stresses corresponds to laminar and transitional Reynolds numbers. The results of measurement of the pulsations of the friction argue the absence of flow conditions of a gas-liquid mixture without pulsations, even with very small Reynolds numbers. The article proposes the possibility of the development of the “pseudoturbulent” transverse transfer of momentum due to the oscillating motion of the bubbles in the channel. A detailed explanation of an analogous effect in the hydrodynamics of blood was given by Regirer [3]. |
