Repeat Prob. 4–103 except that the dye is introduced from t = 0 to t = 10 s, and the streaklines are to be plotted at t = 12 s instead of 10 s.

Data from Problem 103

Consider the two-dimensional Poiseuille flow. The fluid between the plates is water at 40°C. Let the gap height h = 1.6 mm and the pressure gradient dP/dx = –230 N/m³. Calculate and plot seven streaklines generated from a dye rake that introduces dye streaks at x = 0 and at y = 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, and 1.4 mm (Fig. P4–103). The dye is introduced from t = 0 to t = 10 s, and the streaklines are to be plotted at t = 10 s.

Fig. P4–103

h Dye rake X u(y)