The use of micro-electrodes in the study of the flow regimes in a packed bed reactor with single phase liquid flow

Abstract The utilization of micro-electrodes in a non-conducting wall with subsequent signal analysis allowed the determination and the study of the flow regimes in a packed bed reactor with single-phase liquid flow. In effect, the analysis of the rate of fluctuation of the liquid—solid mass transfer coefficient (velocity gradient) as a function of liquid flow rate clearly showed the transition between inertial flow regime (nonlinear steady-state laminar) and turbulent flow regime. This transition, located between Reynolds number values of 110 and 370, corresponds to an unsteady-state laminar flow regime. Examination of the power spectral densities of these fluctuations led to a better understanding of liquid flow behaviour during this transition.