For a 3-cm thick slab that can be taken to be infinite in the x- and y-directions, the steady temperatures at z = 0 and z=3 cm are 97°C and 27°C, respectively. a) Compute the heat flux vector through the slab for k= 2.1 W/(m K). b) Compute the heat flux vector through the slab for k= [2.1 +0.05(T-300 K)/K] W/(m K). c) Compute the heat flux vector through the slab for k= [2.1 +0.05(T-62°C)/K] W/(m K).

For a 3-cm thick slab that can be taken to be infinite in the x- and y-directions, the steady temperatures at z = 0 and z=3 cm are 97°C and 27°C, respectively. a) Compute the heat flux vector through the slab for k= 2.1 W/(m K). b) Compute the heat flux vector through the slab for k= [2.1 +0.05(T-300 K)/K] W/(m K). c) Compute the heat flux vector through the slab for k= [2.1 +0.05(T-62°C)/K] W/(m K).

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

The left side of a composite wall is kept at 300oC constantly. The right side of the same wall is exposed to air at 20oC with a convection coefficient of 32 W/mk. kA = 10 W/mK, kB = 40 W/mK, kC = 1 W/mK, kD = 300 W/mK, kE = 0.1 W/mK Given figure 1, calculate: a) The total thermal resistance of the wall.b) The total heat rate through the wall.c) The junction temperature where B meets D (between second and third column)
Problem 1. 67 pts bar shown below, determine the temperatures at Nodes 2 and 3. Assume 1-D heat transfer that only occurs in the x-direction as the upper and lower 1-D Heat Transfer with Conduction. For the 1-D composite boundaries of the elements are insulated. Assume the cross-sectional area is the same for all elements, A=0.01 m?. For Element 1, let the thermal conductivity be 100 W/(m °C). For Element 2, let the thermal conductivity be 110 W/(m °C). For Element 3, let the thermal conductivity be 120 W/(m °C). The left end of the bar has a constant temperature of 120 °C (at Node 1) and the right end has a constant temperature of 276 °C (at Node 4). Insulated, 1-d heat transfer in x-dir Node 1 Node 2 Node 3 Node 4 +x 120°C E1 E2 ЕЗ 276°C 1 mm 2 mm 0.5mm Insulated
3.4 Estimate the rate of heat loss due to radiation from a covered pot of water at 95 ° C. How does this compare with the 60 W that is lost due only to convection and conduction losses? What amount of energy input would be needed to maintain the water at its boiling point for 30 minutes? The polished stainless steel pot is cylindrical, 20 cm in diameter and 14 cm high, with a tight-fitting flat cover. The air temperature in the kitchen is about 25 ° C. State any assumptions you make in deriving your estimates
As shown in the sketh below, a steam pipe of 0.12-m inside diameter is insulated with a layer of calcium silicate. "2. Ta2} 1. Ta,1} Steam Insulation (a) If the insulation is 10 mm thick and its inner and outer surfaces are maintained at T, = 800 K and Ta = 490 K. respectively,. what is the rate of heat loss per unit length (q) of the pipe, in W/m? (b) Determine the rate of heat loss per unit length (d), in W/m, and outer surface temperature T,2, in K, for the steam pipe with the Inner surface temperature fixed at T = 800 K, inner radius = 0.06 m, and outer radius n = 0.18 m. The outer surface is exposed to an airflow (T 25°C) that maintains a convection coefficient of h = 25 W/m2-K and to large surroundings for which Tur = T, = 25°C. The surface emissivity of calcium silicate is approximately 0.8.
Σ 00 6. B %24 https/0253A%252F%252Fnewconnect.mheducation.com%252F#/activity/question- CH-3) 6 Help Save & Exit i Required information A 14-cm × 20-cm circuit board houses on its surface 100 closely spaced logic chips, each dissipating 0.06 W in the environment at 40°C. The heat transfer from the back surface of the board is negligible. If the heat transfer coefficient on t1 of 3 the surface of the board is 10 W/m².K. Calculate the heat flux on the surface of the circuit board in terms of W/m (Round the final answer to two decimaj places.) Numeric Response Mc Graw < Prev 4. 11:35 18°C Partly sunny 9N3 ツゆ v 23/10/2021 tio SU 61 & 23 3 4. 5. н alt gr curi
A thin bar of length L = 3 meters is situated along the x axis so that one end is at x = 0 and the other end is at x = 3. The thermal diffusivity of the bar is k = 0.4. The bar's initial temperature f(x) = 300 degrees Celsius. The ends of the bar (x = 0 and x = 3) are then put in an icy bath and kept at a constant O degrees C. Let u(x, t) be the temperature in the bar at x at timet, with t measured in seconds. Find u(x, t) and then u7 (2, 0.1). Put uz (2, 0.1) calculated accurately to the nearest thousandth (3 decimal places) in the answer box.
Consider the following cases: Case 1: A rod with specified surface temperature. Case 2: A rod with specified surface temperature with heat generation. Case 3: A rod with specified surface temperature with variable thermal conductivity k=k(1+BT), ß: is constant. The quadratic temperature profile T(r)= f(r) will be in:
A wood fire with a temperature of 1110F is at the other side of a 10 square ft wall that has a 6-inch layer of firebrick, 3-inch layer of concrete, and 6 inches of regular bricks. The thermal conductivity in Btu of each material is as follows: 0.27, 0.76, and 0.98 respectively hr-ft-° Solve for the heat conducted through this wall and the temperatures measured between the layers if the temperature at the other end of the wall is 150F?
1- Microwave radiation is incident on one side of a planar wall with a heat conductivity coefficient k. (x=0) -D°b=(x)b leads to volumetric heating. While this surface is 9(W/m²) microwave radiation is fixed. kept at a constant temperature To, the other surface at x=L is very well insulated. Determine the temperature distribution T(x) in terms of x, L, k, qo and To.
You are designing a PCB laid horizontally on the ground. The PCB surface temperature can’t exceed 85℃ and has a size of 96mm x 90mm. Tinfinity = 45oC. "p" is the perimeter of the plate a) Calculate the Rayleigh number. b) If the PCB is laid hot-side UP, what is the Nusselt number and heat transfer coefficient? c) If the PCB is laid hot-side DOWN, what is the Nusselt number and heat transfer coefficient? d) Given your results from b and c, which one has better heat transfer? In that case, what is the maximum power dissipation the board can put out? Properties of Air:k = 0.025 W/mkPr = 0.72v = 1.847 x 10−5u = 16.84 x10−6p = 1.2 kg/m3B =1/ Tf (idwal gass)
25- c) A plane wall is having width ‘b’ mm and height 4 times of its width. The wall thickness is 120 mm. the thermal conductivity is 18 W/mK. The surface temperatures are at 700oC and 200o C The heat flow across the plane wall is 746 W Calculate the width, height and area of the wall?
My buddy is starting to get hypothermic (body temperature 306 K) during an epic backcountry ski adventure. Since I'm quite warm (body temperature 310 K), I decide to get in a sleeping bag with him to try and warm him up. What heat transfer mechanism will be most responsible for heating him up? For simplicity, ignore any internal temperature differences across my body (that is, assume my skin temperature is also 310 K). Use numbers to support your answer (for human skin, you can use the following values: surface area A = 1:50 m2, emissivity = 0:970, thickness d = 0:0250 m, thermal conductivty 0:200 JmsK)