Questions from Thermal Fluid Science

Q: Repeat Prob. 18–87 with the heat transfer coefficient at

Repeat Prob. 18–87 with the heat transfer coefficient at the top and the bottom surfaces of each block being doubled to 80 W/m2⋅K. Data from Prob. 18-87: Consider...

Q: A hot dog can be considered to be a cylinder 5 in

A hot dog can be considered to be a cylinder 5 in long and 0.8 in in diameter whose properties are ρ = 61.2 lbm/ft3, cp = 0.93 Btu/lbm⋅°F, k = 0.44 Btu/h⋅ft⋅°F, and α = 0.0077 ft2/h. A hot dog initial...

Q: What is forced convection? How does it differ from natural convection

What is forced convection? How does it differ from natural convection? Is convection that is caused by winds forced or natural convection?

Q: Consider two identical 4-kg pieces of roast beef. The

Consider two identical 4-kg pieces of roast beef. The first piece is baked as a whole, while the second is baked after being cut into two equal pieces in the same oven. Will there be any difference be...

Q: The upper surface of a 50-cm-thick solid plate

The upper surface of a 50-cm-thick solid plate (k = 237 W/m⋅K) is being cooled by water with temperature of 20°C. The upper and lower surfaces of the solid plate are maint...

Q: A 2-cm-high cylindrical ice block (k =

A 2-cm-high cylindrical ice block (k = 2.22 W/m⋅K and α = 0.124 × 10−7 m2/s) is placed on a table on its base of diameter 2 cm in a room at 24°C. The heat transfer coefficient on the exposed surfaces...

Q: A short brass cylinder (ρ = 8530 kg/m3,

A short brass cylinder (ρ = 8530 kg/m3, cp = 0.389 kJ/kg⋅K, k = 110 W/m⋅K, and α = 3.39 × 10−5 m2/s) of diam...

Q: To defrost ice accumulated on the outer surface of an automobile windshield

To defrost ice accumulated on the outer surface of an automobile windshield, warm air is blown over the inner surface of the windshield. Consider an automobile windshield (kw = 1.4 W/mâ‹
...

Q: Reconsider Prob. 18–91. Using appropriate software, investigate

Reconsider Prob. 18–91. Using appropriate software, investigate the effect of the cooling time on the center temperature of the cylinder, the center temperature of the top surface of...

Q: The U.S. Department of Energy estimates that 570,

The U.S. Department of Energy estimates that 570,000 barrels of oil would be saved per day if every household in the United States lowered the thermostat setting in winter by 6°F (3.3°C). Assuming the...