8HP Transport Phenomena - April'2000
Part A (20 x 2 = 40 Marks)
- What are the units of kinematic viscosity?
- Define Newtonian fluids
- What are Bingham plastics?
- Write down the the momentum balance equation
- Define compressible and incompressible fluids
- For Newtonian fluids flowing through two parallel infinite flat plates, the average velocity is __________ of maximum velocity
- Write down the dimensionless numbers
- Define Nusselt number
- Define friction factor
- Write the continuity equation
- Define porosity
- What is hydraulic radius?
- Write down the Brinkman number
- How is thermal diffusivity defined?
- What are the limitations on the relation Cp - Cv = R?
- State Fick's second law of diffusion
- Define molar average velocity
- What is the effect of pressure on diffusivity?
- Define mass flux
- What is diffusion?
Part B (5 x 12 = 60 Marks)
- Prove that the flow of a liquid in laminar flow between two infinite parallel flat plates is given by
Po - PL = 12mVavgL / a2
where L is length of plate in the direction of flow, a is the distance between plates.
- A test on water in a capillary viscometer gave the following data:
Flow rate = 880 mm3/sec, Tube length = 1 m, Tube diameter = 0.5 mm, Pressure drop = 10 mPa. Determine the viscosity of water and test the flow is in laminar region.
- Derive the Navier-Stokes equation.
- Derive the Hagen-Poiseuillie equation by the application of Navier-Stokes equation.
- (a) Explain with a neat figure, the velocity distribution for turbulent flow in tubes.
(b) Write down the equations for three regions of turbulent flow.
- (a) Define friction factors for flow in conduits and for flow in submerged objects.
(b) Write down the Blake-Kozeny equation and Burke-Plummer equation.
- Derive the equations for temperature profile and heat flow at the surface for heat conduction with an electrical source.
- A furnace is constructed with 225 mm of fire brick, 120 mm of insulating brick, 225 mm of building brick. The inside temperature is 1200 K and the outside temperature 330 K. If the thermal conductivities are 1.4, 0.2 and 0.7 W/m.K, find the heat loss per unit area and the temperature at the junction of the fire brick and insulating brick.
- Derive the equation for diffusion through a stagnant gas film.
- Derive the equations of continuity for a binary mixture.