Problem 1. (a) Estimate the transition length at the entrance to a 15 mm tube through...

 

Transcribed Image Text:

Problem 1. (a) Estimate the transition length at the entrance to a 15 mm tube through which 100 percent glycerol at 60C is flowing at a velocity of 0.3 m/sec. The density of glycerol is 1.240 Kg/m. (b) Repeat part (a) for 100 percent n-propyl alcohol entering a 3 in. pipe at 30C and a velocity of 7 ft/sec. The density of nopropyl alcohol is 50 lb/ft. Problem 2. For the following situations of steady state flow, determine whether flow is laminar or turbulent. (a) water at 10 C flowing at an average velocity of 0.1 m/sec in a 100 mm pipe. (b) Water at 10 C flowing at an average velocity of 2 m/sec in a 100 mm pipe. (c) air at 2 atm pressure and 180 F flowing at 50 ft/sec in a 12 inch duct. (c) oil with a specific gravity of 0.78 and a viscosity of 10 cp flowing at 5 ft/sec in a 2 inch pipe; and (d) polymer melt with a density of 900 kg/m3 and a viscosity of 1 Pa.sec flowing at 0.2 m/sec in a 15 mm tube. Problem 3. The apparent viscosity of a non-newtonian liquid at a given shear rate is the value indicated by a viscometer operating on the liquid at that shear rate. It is the viscosity that would be indicated by the viscometer if the liquid were Newtonian. (a) Calculate the apparent viscosity of a 4 percent suspension of paper pulp in water at shear rates du/dy of 20/sec and 1500/sec. (b) Repeat for a 25 percent suspension of clay in water. Problem 1. (a) Estimate the transition length at the entrance to a 15 mm tube through which 100 percent glycerol at 60C is flowing at a velocity of 0.3 m/sec. The density of glycerol is 1.240 Kg/m. (b) Repeat part (a) for 100 percent n-propyl alcohol entering a 3 in. pipe at 30C and a velocity of 7 ft/sec. The density of nopropyl alcohol is 50 lb/ft. Problem 2. For the following situations of steady state flow, determine whether flow is laminar or turbulent. (a) water at 10 C flowing at an average velocity of 0.1 m/sec in a 100 mm pipe. (b) Water at 10 C flowing at an average velocity of 2 m/sec in a 100 mm pipe. (c) air at 2 atm pressure and 180 F flowing at 50 ft/sec in a 12 inch duct. (c) oil with a specific gravity of 0.78 and a viscosity of 10 cp flowing at 5 ft/sec in a 2 inch pipe; and (d) polymer melt with a density of 900 kg/m3 and a viscosity of 1 Pa.sec flowing at 0.2 m/sec in a 15 mm tube. Problem 3. The apparent viscosity of a non-newtonian liquid at a given shear rate is the value indicated by a viscometer operating on the liquid at that shear rate. It is the viscosity that would be indicated by the viscometer if the liquid were Newtonian. (a) Calculate the apparent viscosity of a 4 percent suspension of paper pulp in water at shear rates du/dy of 20/sec and 1500/sec. (b) Repeat for a 25 percent suspension of clay in water.