The wall of a furnace has an inner temperature of 500 F. The wall has a thickness of 2 inches and has a thermal conductivity of 0.02 Btu/(h·ft·F). On the outside, air at 30 F flows over the 10 ft x 10 ft wall at a speed of 10 ft/s. Determine the rate of heat loss from the furnace to the environment. Ensure the V speed is accounted for

An iron bar 2.0 cm x 3.0 cm x 10.0 cm at a temperature of 95 °C is dropped into a barrel of water at 25 °C. The barrel is large enough so that the water temperature rises negligibly as the bar cools. The rate at which heat is transferred from the bar to the water is given by the expression Q (J/min) = UA (T₁-T) where U = 0.05 J/(min cm °C)] is a (cm) is the exposed surface area of the bar, T, and T are the surface temperature of the bar and the water temperature, respectively. The heat capacity of the bar is 0.46 J/g °C). Heat conduction in iron is rapid enough for the temperature T, to be considered uniform throughout the bar. a) Write an energy balance on the bar b) Plot the expected plot of T, versus t and then curve fitting. M = (60 cm³) (7.7 g/cm³) = 462 g C, = 0.46 kJ/(kg-°C), T = 25°C U= 0.050 J/(min-cm².°C) 4 = 2[(2)(3)+(2)(10)+(3)(10)]cm² = 112 cm²

The wall of a furnace has an inner temperature of 500 F. The wall has a thickness of 2 inches and has a thermal conductivity of 0.02 Btu/(h·ft·F). On the outside, air at 30 F flows over the 10 ft x 10 ft wall at a speed of 10 ft/s. Determine the rate of heat loss from the furnace to the environment.

An oil has 0.62 inch steel tube, through which flows an oil. The properties of oil are as follows; μ = 0.034 lbs/ft-sec, μb = 0.044 lbs/ft-sec, μw = 0.004 lbs/ft-sec, and specific gravity at 60°F is 0.899. The oil neters at a temperature of t1 = 60°F and flows with an average velocity of 4 ft/sec. The inside surface area is 0.1613 ft2 per foot length, and the inside sectional area is 0.3019 in2. The length of one pass of the tube is 10 feet. Considering steam at 215°F surround the tubes. Assume that the inside surface temperature of the pipe is 210°F and a bulk temperature of 72°F. If the specific heat of oil is 0.5 btu/lbs-°F and its conductivity k = 0.08 Btu-ft/hr-°F-ft2, what is the temperature at the end of 10 feet pass. Answer: t = 61.18 °F Show the complete solution.

Water vapor enters a Lule with an input cross-sectional area of 0.02 m2 at a temperature of 1.8 MPa and 400C. Water vapor passes through the Lule with a flow of 5 kg/s, and in this process there is a heat loss of 2.8 kJ / kg from the Lule. If the pressure at the outlet is 1.4 MPa and the speed is 275 M/s, find the speed at which the water vapor enters the Lule and the temperature at the outlet of the Lule.