Determine the temperature distribution and heat flow rate per meter length in a long concrete block having the shape shown below. The cross-sectional area of the block is square and the hole is centered.
GIVEN
A long concrete block having the shape shown below
The cross-sectional area of the block is square
The hole is centered
FIND
(a) The temperature distribution in the block
(b) The heat flow rate per meter length
ASSUMPTIONS
The heat flow is two dimensional and in steady state
The thermal conductivity in the block is uniform
SKETCH
The temperature distribution and heat flow rate may be estimated with a flux plot
(a) The temperature distribution is given by the isotherms in the flux plot.
(b) The number of flow lanes (M) = 2 ? 21 = 42
The number of squares per lane (N) = 4
Therefore, the shape factor is
From the rate of heat flow per unit length is
You might also like to view...
In an analysis relating Bohr's theory to the de Broglie wavelength of electrons, when an electron moves from the n = 1 level to the n = 3 level, the circumference for its orbit becomes 9 times greater. This occurs because:
a. the wavelength of the electron becomes nine times as long. b. there are triple as many wavelengths, and each wavelength is triple in length. c. there are nine times as many wavelengths in the new orbit. d. the electron is moving nine times as fast.
A particle (mass = 4.0 g, charge = 80 mC) moves in a region of space where the electric field is uniform and is given by Ex = ?2.5 N/C, Ey = Ez = 0 . If the velocity of the particle at t = 0 is given by vx = 80 m/s, vy = vz = 0, what is the speed of the particle at t = 2.0 s?
a. 40 m/s b. 20 m/s c. 60 m/s d. 80 m/s e. 180 m/s
An artificial satellite in a low orbit circles the earth every 98 minutes. What is its angular speed in rad/s?
What will be an ideal response?
Nonbelt asteroids can become trapped in the _______________ along Jupiter's orbit
Fill in the blank(s) with correct word