Peristaltic Pumping of a Non-Newtonian Fluid

The flow induced by sinusoidal peristaltic motion of the tube wall of a non-Newtonian fluid obeying Herschel-Bulkley equation (a general rheological equation that represents a power-law, Bingham and Newtonian fluid for particular choice of parameters) under long wavelength and low Reynolds number approximation is investigated. The results obtained for flow rate, pressure drop and friction force are discussed both qualitatively and quantitatively and compared with other related studies. It is found that the pressure drop increases with the flow rate and yield stress but decreases with the increasing amplitude ratio. The flow behaviour index shows significant impact on the magnitude of the pressure drop. The pressure-flow rate relationships in Bingham and Newtonian fluid models are found to be linear whereas the same are non-linear in power-law and Herschel-Bulkley models. The friction force possesses the character similar to the pressure drop (an opposite character to the pressure rise) with respect to any parameter.