Explain the mechanism of thermal conduction in solids with the help of a suitable example.

Derive an expression for heat flow through the composite cylinders, using a sectional diagram.

What is unsteady state heating or cooling? Explain about Newtonian heating or cooling.

A copper plate 2 mm thick is heated upto 400°C and then quenched into water at 20°C. Find the time required for the plate to reach the temperature of 40°C. (Assume h heat transfer coefficient 80 kcal/m^2 hr°C, Plate dimensions 30 cm x 30 cm, C p 0.091 Kcal/kg-°C, p =8800

Derive the expression for heat transfer coefficient, when temperature distribution is known.

Air flows over a thin plate with a velocity of 2·5 m/s. The plate is 100 cm x 100 cm. Estimate the boundary layer thickness at the traiting edge of the plate and the force necessary to hold the plate.

(Take u =0·86 x Ns/m^2 and p =1·12

With reference to radiation, explain about the special properties of the shape factor.

Find the shape factor for the given configuration and heat exchange between 1 and if T1 T2 E1 =0·8 and E2 0.9.

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Explain briefly the different types of heat exchangers.

What is fouling of heat exchangers Brief about fouling processes and factors affecting them.

Briefly write about Boiling Heat Transfer
and Nature of Vaporization Phenomena.

Steam at 0·65 bar condenses on a vertical plate 0·6 m square. If the surface temperature of the plate is maintained at 15°C, estimate the rate of condensation.
[Take Ts =37.7°C,
hfg (at 0·065 bar) =2412 x 10^3 J/kg.

The properties of water at mean temperature of 26.4°C [37.7 are

given below:

p=1000 u=864 x kg/ms, k =0.913

7. Write short notes on the following:

Solar Radiation

Heisler Charts

Logarithmic Mean Temperature Difference (LMTD)

Transient Heat Conduction