Questions from Thermal Fluid Science

Q: The velocity profile in fully developed laminar flow in a circular pipe

The velocity profile in fully developed laminar flow in a circular pipe of inner radius R = 2 cm, in m/s, is given by u(r) = 4(1 − r2/R2). Determine the average and maximum velocitie...

Q: Repeat Prob. 14–33 for a pipe of inner radius

Repeat Prob. 14–33 for a pipe of inner radius 7 cm. Data from Prob. 14-33: The velocity profile in fully developed laminar flow in a circular pipe of inner radius R = 2 cm, in m/s,...

Q: Water at 10°C (ρ = 999.7 kg

Water at 10°C (ρ = 999.7 kg/m3 and μ = 1.307 × 10−3 kg/m·s) is flowing steadily in a 0.12-cm diameter, 15-m-long pipe at an average velocity of 0.9 m/s. Determine (a) the pressure drop, (b) the head l...

Q: Consider laminar flow of a fluid through a square channel with smooth

Consider laminar flow of a fluid through a square channel with smooth surfaces. Now the average velocity of the fluid is doubled. Determine the change in the head loss of the fluid. Assume the flow re...

Q: Repeat Prob. 14–36 for turbulent flow in smooth pipes

Repeat Prob. 14–36 for turbulent flow in smooth pipes for which the friction factor is given as f = 0.184Re−0.2. What would your answer be for fully turbulent flow in a rough pipe?

Q: The acceleration of high-speed aircraft is sometimes expressed in g’s

The acceleration of high-speed aircraft is sometimes expressed in g’s (in multiples of the standard acceleration of gravity). Determine the upward force, in N, that a 90-kg man would experience in an...

Q: List the forms of energy that contribute to the internal energy of

List the forms of energy that contribute to the internal energy of a system.

Q: Air enters a 10-m-long section of a rectangular

Air enters a 10-m-long section of a rectangular duct of cross section 15 cm × 20 cm made of commercial steel at 1 atm and 35°C at an average velocity of 5 m/s. Disregarding the...

Q: Consider an air solar collector that is 1 m wide and 4

Consider an air solar collector that is 1 m wide and 4 m long and has a constant spacing of 3 cm between the glass cover and the collector plate. Air flows at an average temperature of 45°C...

Q: Consider a person walking first in air and then in water at

Consider a person walking first in air and then in water at the same speed. For which motion will the Reynolds number be higher?