Mathematical model for blood flow through a bifurcated artery using couple stress fluid

•The blood flow through a bifurcated artery with mild stenosis is investigated.•Flow rate increased with an increase of all the parameters in parent and daughter arteries.•Impedance decreased with an increase of all the parameters in parent and daughter arteries.•Shear stress is decreasing with an increase in the values of couple stress fluid parameters.•Shear stress increased with increase of bifurcation angle along the inner wall of daughter artery.

In this article, the blood flow through a bifurcated artery with mild stenosis is investigated taking blood as couple stress fluid. The artery configuring bifurcation is assumed to be symmetric about the axis of the artery and straight cylinders of finite length. The governing equations are non-dimensionalized and coordinate transformation is used to convert the irregular boundary to a regular boundary. The resulting system of equations is solved numerically using the finite difference method. The variation of shear stress, flow rate and impedance near the apex with pertinent parameters are studied graphically. It has been noticed that shear stress, flow rate and impedance have been changing suddenly with all the parameters on both sides of the apex. This occurs because of the backflow of the streaming blood at the onset of the lateral junction and secondary flow near the apex in the daughter artery.