Resistance in a Developing Low-Amplitude Pulsating Laminar Flow in a Flat Channel

In this paper, we present a mathematical model and a numerical simulation technique based on boundary layer theory for a developing low-amplitude pulsating laminar flow in a flat channel. The calculation results were obtained and the analysis of influence of the pulsating flow on the hydraulic and friction resistances was carried out. At pulsation amplitudes of more than 2/3 of the average cross-sectional velocity, the transverse component of velocity begins to affect the flow. The relations between the changes in the coefficients of both hydraulic resistance and friction resistance are presented and analyzed. Over the entire settling length, while increasing the dimensionless pulsation frequency, the pulsation amplitude of the hydraulic resistance coefficient increases much more compared to the friction resistance coefficient. The dependences of the amplitude and phase of the resistance pulsations are presented, which make it possible to restore their initial values.