Q.1.
The maximum velocity of the turbulent regime is called the ___________ at which the fast fluidization regime occurs.
- a) Terminal velocity
- b) Transport velocity
- c) Superficial velocity
- d) Average velocity
Q.2.
What happens at velocities above the transport velocity?
- a) Particles coagulate
- b) Particles are carried out of the system by the fluid
- c) Particles break into smaller parts
- d) Particles accumulate at the top
Q.3.
Which one of the following working model is best suited for fluidized bed combustion boilers?
- a) Bubbling fluidized beds
- b) Laminar film fluidised bed
- c) Pneumatic conveying regime
- d) Moving bed (Dense flow)
Q.4.
Parameters that describe the overall behaviour of the fluidized bed in the bubbling regime are:
- a) (i) (ii)
- b) (ii) (iii) (iv)
- c) (i) (ii) (iii) (iv)
- d) (i) (ii) (iii)
Q.5.
Which one of the following method is the most reliable when it comes to determine fluidisation point?
- a) Pressure Drop
- b) Top surface particles starting random movement
- c) Half of the particles getting free
- d) All particles are free
Q.6.
What is the correct expression for pressure drop in a fluidised bed at fluidisation?
- a) ΔP=(1-∈)(ρP-ρg)gHB
- b) ΔP=(∈)(ρP-ρg)gHB
- c) ΔP=(1-∈)(ρP-ρg)gHC
- d) ΔP=(1-∈)(ρP)gHB
Q.7.
If the operation on a fluidised bed is a dense flowing fixed bed, then which one of the following method is used for pressure drop calculation?
- a) Sieder Tate Equation
- b) Ergun Equation
- c) DeMentic Equation
- d) Kozeny Carman Equation
Q.8.
Which one of the heat transfer processes are not involved in a fluidised bed?
- a) Gas-wall heat transfer
- b) Heat transfer between different points in the bed
- c) Heat transfer between the fluidized bed particles and the larger particles floating in the bed
- d) Heat transfer to the submerged surfaces in contact with the bed
Q.9.
On complete fluidisation, which one of the following is zero?
- a) Gas-particle heat transfer
- b) Heat transfer between different points in the bed
- c) Heat transfer between the fluidized bed particles and the larger particles floating in the bed
- d) Heat transfer to the submerged surfaces in contact with the bed
Q.10.
If there arepellets of 3mm diameter, what is the heat transfer area?
- a) 0.02m2
- b) 0.05m2
- c) 0.04m2
- d) 0.03m2
Q.11.
Active particles which are quite large sternly repel the emulsion phase and hence the mass transfer rate augments with the ________ of the inert bed material size and _________ with increase of its active particle’s diameter.
- a) Increase, Decrease
- b) Increase, Increase
- c) Decrease, Increase
- d) Decrease, Decrease
Q.12.
Heat transfer between the active particle and the fluidized bed is controlled by three mechanisms given below, identify the wrong entry.
- a) Radiation
- b) Gas convection
- c) Particle convection
- d) Particle conduction