Concept explainers
A cubical glass melting furnace has exterior dimensions of width
Want to see the full answer?
Check out a sample textbook solutionChapter 4 Solutions
Fundamentals of Heat and Mass Transfer
- 1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed to temperature of –5°C, while the inner surface is kept at 20°C. The thermal conductivity of the concrete is 1.2 W/m K. Determine the heat loss through the wall, which is 10-m long and 3-m high. Problem 1.1arrow_forwardA glass window of width W = 1 m and height H = 2 m is 5 mm thick and has a thermal conductivity of kg =1.4 W/m.K. If the inner and outer surface temperatures of the glass are 15 oC and -20 oC, respectively, on a cold winter day, what is the rate of heat loss through the glass? To reduce heat loss through windows, it is customary to use a double pane construction in which adjoining panes are separated by an air space. If the spacing is 10 mm and the glass surfaces in contact with the air have temperatures of 9oC and -15 oC, what is the rate of heat loss from a 1 m x 2 m window? The thermal conductivity of air is ka = 0.024 W/m.K.arrow_forwardsend me paper solution in proper writingarrow_forward
- Required information Consider a 5-m-high, 8-m-long, and 0.22-m-thick wall whose representative cross section is as given in the figure. The thermal conductivities of various materials used, in W/m-K, are kA=kF=2, kg-8. kc-20, kp=15, and ke-35. The left and right surfaces of the wall are maintained at uniform temperatures of 345°C and 100°C, respectively. Assume heat transfer through the wall to be one-dimensional. Disregard any contact resistances at the interfaces. 1 cm. A4 cm B 4 cm रेव 4 cm Sem 6 cm DI 4 E 6 cm F 10 cm 6 cm 100°C 8m Determine the rate of heat transfer through the wall (in W).arrow_forwardthere is no radius only given thicknessarrow_forwardplz answer this,ASAP,thx At high temperatures a nuclear reactor consists of a cylindrical wall composite as the fuel element thorium (k = 57 W/mK) wrapped in graphite (k = 3 W/mK) and helium gas flows through a circular cooling channel. Cylinder length 200 mm. Taking into account the helium temperature = 600°C and the convection coefficient, h= 200 W/m²K. When measured, the outside temperature is 100°C, and h = 5 W/m².K. Draw the electrical analogy, and calculate the overall heat transfer rate!arrow_forward
- You want to figure out whether it is safe to touch the outside surface of the pipe in question. Here are the details: "A stainless steel pipe is carrying hot water to a test facility. The inside surface of the pipe is at a temperature of 70°C and the inner radius is 0.2 m. The thickness of the steel pipe is 12 mm. It is exposed to air at 30°C on the outside. The average convection coefficient of air over the pipe is 15 W/m².°C. Thermal conductivity of steel is 54 W/m.°C. Negelect radiation. Consider steady conditions." Calculate, assuming a 1-m long pipe segmen, the temperature of the outside surface of the pipe.arrow_forwardOne vessel having a carbon-steel wall of thickness 5 mm carrying saturated steam and water at 423K. The vessel is insulated with magnesia of thickness 50 mm. If the ambient air temperature is 321 K, determine the heat loss from the vessel. Given: i. thermal conductivity of carbon steel is 52 W/m.K ii. thermal conductivity of magnesia is 0.5 W/m.K iii. surface coefficient of insulation surface is 3 W/m2.Karrow_forward1. Consider a 5-m-high, 8-m-long, and 0.22-m-thick wall whose representative cross section is as given in the Fig. The thermal conductivities of various materials used, in W/m-°C, are k = kr = 2, KB = 8,kc=20, KD = 15, and k = 35. The left and right surfaces of the wall are maintained at uniform temperatures of 300 °C and 100 °C, respectively. Assuming heat transfer through the wall to be one-dimensional, determine: (a) the rate of heat transfer through the wall; (b) the temperature at the point where the sections B, D, and E meet; and (c) the temperature drop across the section F. Disregard any contact resistances at the interfaces. 300°C 1 cm C A 4 cm B 4 cm 4 cm D C 6 cm 5 cm 6 cm E| F 10 cm 6 cm 100°C 8 marrow_forward
- The hot combustion gases of a furnace are separated from the ambient air and its surroundings, which are at 25°C, by a brick wall 0.15 m thick (Figure la). The brick has a thermal conductivity of 1.2 W/m·K and a surface emissivity of 0.8. Under steady-state conditions an outer surface temperature of 100°C is measured. Free convection heat transfer to the air adjoining the surface is characterized by a convection coefficient of h = 20 W/m².K. What is the brick inner surface Q1 a) temperature?arrow_forwardSolve correctlyarrow_forwardQuestion 1:A glass window of width W = 1 m and height H = 2 m is 5 mm thick and has a thermal conductivity of kg=1.4 W/m.K. If the inner and outer surface temperatures of the glass are 15oC and -20oC, respectively, ona cold winter day, what is the rate of heat loss throughthe glass? To reduce heat loss through windows, it iscustomary to use a double pane construction in whichadjoining panes are separated by an air space. If thespacing is 10 mm and the glass surfaces in contact withthe air have temperatures of (last two digit of your Registration number) oC and -15oC, what isthe rate of heat loss from a 1 m x 2 m window? Thethermal conductivity of air is ka=0.024 W/m.K.arrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning