Problem 4 (20 points)
An oil is being pumped inside a long pipe with a diameter of 10 mm at a Reynolds number of 1000.
The oil density is 800 kg/m³ and the viscosity is 20 mPa.s.
(a) What is the average and maximum velocity in the pipe? (10 points)
(b) If the pipe is replaced by a rectangular channel, shown as the figure, please calculate the
Reynolds number when the volumetric flow rate (m³/s) is the same as in the pipe. (10 points)
10 mm
TO FE
↓
10 mm
