-9- The plate shown in figure is at a uniform surface temperature of L=5m T, = 50°C. Heat is removed by convection to an ambient fluid at T 25 C . The heat transfer coefficient h varies along the surface 1,T. 2m H = 5m according to: h= 87 x Determine the total heat transfer rate from the surface. Answ(32917W)

-9- The plate shown in figure is at a uniform surface temperature of L=5m T, = 50°C. Heat is removed by convection to an ambient fluid at T 25 C . The heat transfer coefficient h varies along the surface 1,T. 2m H = 5m according to: h= 87 x Determine the total heat transfer rate from the surface. Answ(32917W)

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

H.W1 Consider a person standing in a room. Determine the total rate of heat transfer from this person if the exposed surface area and temperature are 1.6m² and 29°C, respectively. Assume that the convection heat transfer coefficient is 6W/m².K and the emissivity of a person is 0.95. The air temperature in the room is maintained at 22°C at all times of the year. In summer, the wall and ceiling temperatures are observed to be 25°C, while in winter, they are 10°C. Ans: Qrotal =104.4 W In Summer Qrotal =231.3 W In Winter
During daytime, the outside air temperature is measured at Ta = 35 °C. A house with an inside temperature of Tin = 20 °C is separated from the outside by a brick wall as shown in Figure 1. i Briefly discuss what will happen in terms of heat transfer process and the mode of heat transfer involved. ii. Identify the parameters that affect the rate of heat transfer in this case T. = T = 35°C 20°C Brick wall
You are designing a 3m x 3m floor with radiant heating. The floor has 12 parallel pex pipes (k = 40 W/mK) of L = 3m, OD = 25mm and ID = 20mm. Hot water (TInfintiy 1 = 90oC, h = 200 W/m2K) runs through the pipes continuously. The surface below the pipes is perfectly insulated. Above the pipes, there is a 3mm layer of bonding material (? = 12 W/mK) and a 9mm layer of tile (k = 2 W/mK). Above the tile, there is air (TInfinity 2 = 25oC, h = 20 W/m2K). Properties of Air: k = 0.025 W/mK, Pr = 0.72, v = 1.847 x 10−5, u = 16.84 x 10−6, p = 1.2 kg/m3, B = 1/Tf (ideal gas), Hint: Assume that the “layer” of pipe starts at the center point (e.g. for conduction purposes, the pipe is OD divided by 2 thick). For convection, consider the entire pipe surface. a) What is the total heat rate entering the room above the floor? b) What is the temperature of the top of the tile?
3 Brass cube "p = 8530 kg/m , c= side length =9 mm, are annealed by heating them first to 813°C in a furnace and then allowing them to cool slowly to 130°C in ambient air at 28°C. If the average heat transfer coefficient is 19.9 W/m .°C, If 2204 balls are to be annealed per hour, what is the total rate of heat transfer (watts) from the balls to the ambient air? 380 J/kg.°C, k = 110 W/m.°C, a = 33.9E-6 W/m.°C",
Q3/ A 6(m) long 2(kW) electrical resistance wire is made of 0.2(cm) diameter stainless steel (k = 15.1 W/m °C). The resistance wire operates in an environment at 30°C with a heat transfer coefficient of 140 (W/m?. °C) at the outer surface. Find the temperature distribution equation and determine the surface temperature of the wire.
Steaks (2 cm thick, k = 0.45 W/m - °C, « = 0.91 x 107 m2/s) usually have an original temperature of 25 °C. They will be cooled in a refrigeration room. The said room has a temperature of -11 °C. The heat transfer coefficient on both sides of the steak is 9 W/m2 - °C. How long will it take for both surfaces of the meat to be cooled to 2 °C? Assume the geometry of steaks to be a flat slab.
The convection coefficient for a hot a fluid flowing over a cool surface is 150 W/m^2. The fluid temperature is 410 K and the surface is held at 290 K. Determine the heat transfer per unit surface area from the fluid to the surface.
Example: Steam in a heating system flows through tubes whose outer diameter isD1=3 cm and whose walls are maintained at: = 1.5 cm 2= 3 cm temperature of 120°C. Circular aluminun fins ( k=180 W/m °C) of outer diamete D2 6 cm and constant thickness t =2 mn T r32 mm are attached to the tube, as shown in Fig The space between the fins is 3 mm, an thus there are 200 fins per meter lengtl of the tube. Heat is transferred to th surrounding air at T= 25°C, with a combined heat transfer coefficient of h= 60 W/m2 °C. Determine the increase in heat transfer from the tube per meter of its length as a result of adding fins. S 3 mm
1 - A square chip, with side w = 5 mm, operates under isothermal conditions.The chip is positioned on a substrate so that its side and bottom surfaces are thermally insulated, while its top surface is exposed to theflow of a refrigerant at T∞ = 15°C. From reliability considerations, the chip temperature cannot exceed T = 85°C. The refrigerant being air, with a convection heat transfer coefficientcorresponding h = 200 W/(m2K), what is the maximum allowable power for the chip? Since the coolant is a dielectric liquid for which h = 3000 W/(m²K), what is the maximum allowed power?
The temperature of a gas stream is measured by a thermocouple whose junction can be approximated as a 1-mm-diameter sphere. Take the junction’s properties as: k of 32 W/m K, density of 8.2 kg/m^3, c of 300 J/Kg K. On its surface, the overall heat transfer coefficient is 200 W/m^2 K. Neglect any conduction loss from the sphere to other parts of the thermocouple. Create a plot of measurement error as a function of time for the thermocouple, expressed as a fraction of the initial temperature difference.