E-PolyLearning

Discussion Forum

Que. A slab of 12 cm thickness and generating heat uniformly at 10⁶ W/m³ has thermal conductivity of 200 W/m degree. Both surfaces of the slab are maintained at 150 degree Celsius. Determine the heat flow rate at the quarter planes
a. 30000 W/m²
b. 40000 W/m²
c. 50000 W/m²
d. 60000 W/m²
Correct Answer:30000 W/m²
Confused About the Answer? Ask fellow aspirants for Details Here
Already Know Explanation? Add it Here to help others.

More Questions Like this:

In case when both the surfaces of plane wall are at different temperature, we get an expression i.e.

T MAX – T W2 /T W1 – TW2 = (B + 1)²/4B

What is the value of B?
If Q X is heat generated in at distance ‘x’, then heat conducted out at a distance (x + d x) will be
A solid sphere of 8 cm radius has a uniform heat generation of 4000000 W/m³. The outside surface is exposed to a fluid at 150 degree Celsius with convective heat transfer coefficient of 750 W/m² K. If thermal conductivity of the solid material is 30 W/m K, determine maximum temperature
The temperature distribution profile for a solid cylinder is
Notable example of uniform generation of heat within the conducting medium are

(i) Energy of a nuclear reactor

(ii) Liberation of energy due to some exothermic chemical reactions

(iii) Resistance heating in electrical appliances

Which of the statements made above are correct?
The temperature drop in a plane wall with uniformly distributed heat generation can be decreased by reducing
A 25 mm diameter egg roll (k = 1 W/m degree) is roasted with the help of microwave heating. For good quality roasting, it is desired that temperature at the center of roll is maintained at 100 degree Celsius when the surrounding temperature is 25 degree Celsius. What should be the heating capacity in W/m³ of the microwave if the heat transfer coefficient on the surface of egg roll is 20 W/m² degree?
What maximum thickness of concrete can be poured without causing the temperature gradient to exceed 98.5 degree Celsius per meter anywhere in the slab? Consider a 1.2 m thick slab of poured concrete (k = 1.148 W/m degree) with both of side surfaces maintained at a temperature of 20 degree Celsius. During its curing, chemical energy is released at the rate of 80 W/m³. Workout the maximum temperature of concrete
Dielectric heating apparatus consists of
There occurs heat conduction and internal heat generation at uniform rate within the conduction medium itself in the following cases
(i) Drying of concrete

(ii) Chemical processes

(iii) Fuel elements in a nuclear reaction

Choose the correct option
Consider heat conduction through a solid sphere of radius R. There are certain assumptions

(i) Unsteady state conditions
(ii) One-dimensional radial conduction
(iii) Constant thermal conductivity

Identify the correct statements
Consider a convective heat flow to water at 75 degree Celsius from a cylindrical nuclear reactor fuel rod of 50 mm diameter. The rate of heat generation is 50000000 W/m³ and convective heat transfer coefficient is I kW/m² K. The outer surface temperature of the fuel element would be
For a plane wall of thickness l with uniformly distributed heat generation q g per unit volume, the temperature t₀ at mid plane is given by
For a cylindrical rod with uniformly distributed heat sources, the thermal gradient at half the radius location will be
A concrete column used in bridge construction is cylindrical in shape with a diameter of 1 meter. The column is completely poured in a short interval of time and the hydration of concrete results in the equivalent of a uniform source strength of 0.7 W/kg. Determine the temperature at the center of the cylinder at a time when the outside surface temperature is 75 degree Celsius. The column is sufficiently long so that temperature variation along its length may be neglected. For concrete
Average thermal conductivity = 0.95 W/m K
Average density = 2300 kg/m³
The insulating material used in dielectric heating is
The constants of integration are to be determined from the relevant boundary conditions which are
(i) t = t w at r = R
(ii) q g (π L R²) = -k (2 π R L) (d t/d r)
(iii) Increasing temperature gradient
Choose the correct option?
A slab of insulating material of thickness 6 cm and thermal conductivity 1.4kJ/m hr deg is placed between and is in contact with two parallel electrodes, and is then subjected to high frequency dielectric heating at a uniform rate of 140,000kJ/m³ hr. At steady state coefficients of combined radiation and convection are 42 and 48 kJ/m² hr deg. If atmospheric temperature is 25 degree Celsius, find surface temperatures?
A slab of 12 cm thickness and generating heat uniformly at 10⁶ W/m³ has thermal conductivity of 200 W/m degree. Both surfaces of the slab are maintained at 150 degree Celsius. Determine the heat flow rate at the quarter planes
Identify the correct boundary condition for a hollow sphere with inside surface insulated.

View All Questions on: Conduction With Heat Generation

Management and Accounting

Human Resource Management Marketing and Marketing Management Financial Management and Financial Markets Cost Accounting Business Statistics