Head losses (assignment_3_)
- 1. HEAD LOSSES (ASSIGNMENT 3) 1.A pipe is 25 km long and 80 mm bore diameter. The mean surface roughness is 0.03 mm. It carries oil of density 825 kg/m3 at a rate of 10 kg/s. The dynamic viscosity is 0.025 N s/m2. Determine the friction coefficient using the Moody Chart and calculate the friction head. (Ans.3075 m.) 2.A pipe 120 mm bore diameter carries water with a head of 3 m. The pipe descends 12 m in altitude and reduces to 80 mm bore diameter. The pressure head at this point is 13 m. The density is 1000kg/m3. Assuming no losses, determine i. The velocity in the small pipe (7 m/s) ii. The volume flow rate. (35 dm3/s) 3. A type of fluid to pass from A to B through a pipe of 350 mm diameter galvanized steel with a length of 250 m. Point A is located 9.0 m below the point B and the pressure at B is 125 kPa. If the flow through the pipe is 0.22 m3 / s, determine the pressure at A. Take the kinematic viscosity, v = 0687 x 10 -6 m2 / s and a relative density = 0.86. (Ans : 228.6 kPa) 4.Water is pumped through a 60-m-long, 0.3-m-diameter pipe from a lower reservoir to a higher reservoir whose surfaces 10 m above the lower one. The sum of the minor loss coefficients for the system is KL = 14.5. When the pump adds 40 kW to the water the flowrate is 0.20 m 3/s. Determine the pipe roughness. (Given, µwater = 1.12 x 10-3 N s/m2)
- 2. 5.Water flows through the sudden pipe expansion shown below at a flow rate of 3 dm3/s.Upstream of the expansion the pipe diameter is 25 mm and downstream the diameter is 40 mm. There are pressure tappings at section (1), about half a diameter upstream, and at section (2), about 5 diameters downstream. At section (1) the gauge pressure is 0.3 bar. Evaluate the following. (i) The gauge pressure at section (2) (0.387 bar) (ii) The total force exerted by the fluid on the expansion. (-23 N)