Questions from Thermal Fluid Science

Q: An air-conditioning system requires airflow at the main supply duct

An air-conditioning system requires airflow at the main supply duct at a rate of 130 m3/min. The average velocity of air in the circular duct is not to exceed 8 m/s to avoid excessive vibration and pr...

Q: A building with an internal volume of 400 m3 is to be

A building with an internal volume of 400 m3 is to be heated by a 30-kW electric resistance heater placed in the duct inside the building. Initially, the air in the building is at 14°C, and...

Q: The maximum flow rate of standard shower heads is about 3.

The maximum flow rate of standard shower heads is about 3.5 gpm (13.3 L/min) and can be reduced to 2.75 gpm (10.5 L/min) by switching to low-flow shower heads that are equipped with flow controllers....

Q: Reconsider Prob. 6–157. Using appropriate software, investigate

Reconsider Prob. 6–157. Using appropriate software, investigate the effect of the inlet temperature of cold water on the energy saved by using the low-flow shower head. Let the inlet temperature vary...

Q: What is the driving force for (a) heat transfer,

What is the driving force for (a) heat transfer, (b) electric current, and (c) fluid flow?

Q: The pressure in a natural gas pipeline is measured by the manometer

The pressure in a natural gas pipeline is measured by the manometer shown in Fig. P2–50E with one of the arms open to the atmosphere where the local atmospheric pressure is 14.2 psia...

Q: Steam enters a turbine steadily at 7 MPa and 600°C

Steam enters a turbine steadily at 7 MPa and 600°C with a velocity of 60 m/s and leaves at 25 kPa with a quality of 95 percent. A heat loss of 20 kJ/kg occurs during the process. The inlet area of the...

Q: What are the different mechanisms for transferring energy to or from a

What are the different mechanisms for transferring energy to or from a control volume?

Q: Reconsider Prob. 6–159. Using appropriate software, investigate

Reconsider Prob. 6–159. Using appropriate software, investigate the effects of turbine exit area and turbine exit pressure on the exit velocity and power output of the turbine. Let the exit pressure v...

Q: It is proposed to have a water heater that consists of an

It is proposed to have a water heater that consists of an insulated pipe of 7.5-cm diameter and an electric resistor inside. Cold water at 20°C enters the heating section steadily at a rate of 24 L/mi...