VISCOSITY DATA ON FLOWS OF DISTILLED WATER THROUGH CYLINDRICAL PIPES

Pressure drop measurements on flows of distilled water through cylindrical plexiglass pipes are reported. In certain cases an increase is noted of the apparent dynamic viscosity with increasing rates of flow in agreement with findings reported previously. However, the present experiments indicate a systematic decrease of this effect with decreasing tube diameter, so that even a decrease of the viscosity has been recorded with increasing rate of flow. Furthermore, the experiments indicate a systematic increase of the absolute viscosity values with increasing tube diameter. Author