Questions from Thermal Fluid Science

Q: Show that the thermal resistance of a rectangular enclosure can be expressed

Show that the thermal resistance of a rectangular enclosure can be expressed as R = Lc /(AkNu), where k is the thermal conductivity of the fluid in the enclosure.

Q: Air at 20°C (1 atm) enters into a

Air at 20°C (1 atm) enters into a 5-mm-diameter and 10-cm-long circular tube at an average velocity of 5 m/s. The tube wall is maintained at a constant surface temperature of 160°C. Determine the conv...

Q: Consider a 3-m-high rectangular enclosure consisting of two

Consider a 3-m-high rectangular enclosure consisting of two surfaces separated by a 0.1-m air gap at 1 atm. If the surface temperatures across the air gap are 30°C and −10...

Q: The convection heat transfer coefficient for a clothed person standing in moving

The convection heat transfer coefficient for a clothed person standing in moving air is expressed as h = 14.8V0.69 for 0.15 < V < 1.5 m/s, where V is the air velocity. For a person with a body surface...

Q: Flat-plate solar collectors are often tilted up toward the sun

Flat-plate solar collectors are often tilted up toward the sun in order to intercept a greater amount of direct solar radiation. The tilt angle from the horizontal also affects the rate of heat loss f...

Q: Glycerin is being heated by flowing between two parallel 1-m

Glycerin is being heated by flowing between two parallel 1-m-wide and 10-m-long plates with 12.5 mm spacing. The glycerin enters the parallel plates with a temperature of 25°C and a mass flow rate of...

Q: A vertical 1.5-m-high and 3.

A vertical 1.5-m-high and 3.0-m-wide enclosure consists of two surfaces separated by a 0.4-m air gap at atmospheric pressure. If the surface temperatures across the air gap are measured to be 280 K an...

Q: Reconsider Prob. 19–80. Using appropriate software, evaluate

Reconsider Prob. 19–80. Using appropriate software, evaluate the effect of the glycerin mass flow rate on the surface temperature of the parallel plates and the total rate of heat transfer necessary t...

Q: A vertical 1.5-m-high, 2.

A vertical 1.5-m-high, 2.8-m-wide double-pane window consists of two layers of glass separated by a 2.0-cm air gap at atmospheric pressure. The room temperature is 26°C while the inner glass temperatu...

Q: Air flows in an isothermal tube under fully developed conditions. The

Air flows in an isothermal tube under fully developed conditions. The inlet temperature is 60°F and the tube surface temperature is 120°F. The tube is 10 ft long, and the inner diameter is 2 in. The...