JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech II FLUID MECHANICS AND HEAT TRANSFER Previous Question Paper (February - 2024 - R16)

Define Pascal’s law.

State the conditions for rotational and irrotational flow.

Define vena contracta. State its significance.

What do you mean by the coefficient of discharge?

What do you mean by thermal diffusivity?

State Fourier’s law of conduction.

Define convection heat transfer.

Differentiate free and forced convection.

Define grey body. Give examples.

Show the temperature trend in a counterflow heat exchanger.

Classify the types of fluid flows.

The velocity distribution in a viscous flow over a plate is given by

Explain stream and velocity potential functions.

In a flow field, the velocity components as defined as follows.

Derive the expression for the rate of flow of fluid through an orifice meter.

A 20 cm × 10 cm venturimeter is provided by a vertical pipeline carrying oil of a specific gravity of 0.85. The difference in elevation of the throat section and entrance section of the venturimeter is 0.5 m. The differential U-tube Venturimeter shows a gauge difference of 40 cm. The specific gravity of mercury is 13.6. Calculate the discharge of oil in litres per sec. Take Cd = 0.98.

Derive Bernoulli's equation from Euler's equation.

Discuss the following: i) Body forces, ii) Surface forces.

Derive an expression for a generalized heat conduction equation in a Cartesian coordinate system.

A 30 cm thick wall of the reactor is made up of an inner layer of firebrick

Define thermal conductivity and how it can be measured. Differentiate between thermal conductivity and thermal conductance.

A stainless steel tube (

Explain Rayleigh's method of dimensional analysis.

A glazed window made of 8 mm thick glass of thermal conductivity 1.5 W/m K as its outside surface maintained at 50 °C so that frosting is reduced. The surrounding is at -10 °C with a convective coefficient of 55 W/m²K. The desired condition is attained by providing uniform heat flux at the inner surface of the window which is fitted into a room where the air temperature is 25 °C with a convection coefficient of 12.5 W/m² K. Calculate the heat required per m² area.

Explain the lift and drag phenomenon.

Engine oil at 60 °C flows over a 5 m long flat plate whose temperature is 20 °C with a velocity of 2 m/s. Determine the total drag force and the rate of heat transfer per unit width of the entire plate.

Explain the applications of radiation shields in heat transfer.

A black body of 0.2 m² area has an effective temperature of 800 K. Calculate the total rate of energy emission, the intensity of normal radiation, the intensity of radiation along a direction 60° to the normal and the wavelength of maximum monochromatic emissive power.

Explain the fouling factor and its influence on the heat exchangers.

A furnace is approximated as an equilateral triangular duct of sufficient length so that end effects can be neglected. The hot wall of the furnace is maintained at a temperature of 900 K and has an emissivity of 0.8. The cold wall is at 400 K and has the same emissivity. Find the net radiation heat flux leaving the wall. The third wall of the furnace may be assumed as a reradiating surface.