Steady flow of power-law fluids in a 1:3 planar sudden expansion

► Non-Newtonian power-law fluid flow in a 1:3 planar sudden expansion is analyzed numerically. ► A wide range of power-law index, n, in the range (0.2 ⩽ n ⩽ 4) is considered. ► Flow is strongly dependent on power-law index, n. ► In the creeping flow limit, Moffatt eddies appear and they gradually increase in size when n increases. ► Flow bifurcation is delayed when n < 1 while the same occurs earlier when n > 1 compared to Newtonian fluids (n = 1).