Questions from Thermal Fluid Science

Q: Reconsider the helicopter in Prob. 13–35, except that

Reconsider the helicopter in Prob. 13–35, except that it is hovering on top of a 2200-m-high mountain where the air density is 0.987 kg/m3. Noting that the unloaded helicopter blades...

Q: Water is flowing through a 10-cm-diameter water pipe

Water is flowing through a 10-cm-diameter water pipe at a rate of 0.1 m3/s. Now a diffuser with an outlet diameter of 20 cm is bolted to the pipe in order to slow down water, as shown in Fig. P13&acir...

Q: Water flowing in a horizontal 25-cm-diameter pipe at

Water flowing in a horizontal 25-cm-diameter pipe at 8 m/s and 300 kPa gage enters a 90° bend reducing section, which connects to a 15-cm-diameter vertical pipe. The inlet of the bend is 50 cm above t...

Q: A horizontal 4-cm-diameter water jet with a velocity

A horizontal 4-cm-diameter water jet with a velocity of 18 m/s impinges normally upon a vertical plate of mass 750 kg. The plate rides on a nearly frictionless track and is initially stationary. When...

Q: Express the conservation of momentum principle. What can you say about

Express the conservation of momentum principle. What can you say about the momentum of a body if the net force acting on it is zero?

Q: Water enters a centrifugal pump axially at atmospheric pressure at a rate

Water enters a centrifugal pump axially at atmospheric pressure at a rate of 0.09 m3/s and at a velocity of 5 m/s and leaves in the normal direction along the pump casing, as shown in Fig. P13 40. De...

Q: An incompressible fluid of density ρ and viscosity μ flows through a

An incompressible fluid of density ρ and viscosity μ flows through a curved duct that turns the flow 180°. The duct cross-sectional area remains constant. The avera...

Q: Consider the curved duct of Prob. 13–41, except

Consider the curved duct of Prob. 13–41, except allow the cross-sectional area to vary along the duct (A1 ≠ A2). (a) Write an expression for the horizontal force Fx of the fluid on the walls of the du...

Q: A room is heated as a result of solar radiation coming in

A room is heated as a result of solar radiation coming in through the windows. Is this a heat or work interaction for the room?

Q: As a follow-up to Prob. 13–41,

As a follow-up to Prob. 13–41, it turns out that for a large enough area ratio A2/A1, the inlet pressure is actually smaller than the outlet pressure! Explain how this can be true in...