With increase in gas flow rate to fabric surface area ratio (Nm3/hr/m2 fabric surface area), the size & the cost of a bag filter___________________?

Related Mcqs:

1. Heat transfer co-efficient, hG(Kcal/hr.m2 .°C) and mass velocity of air, G (kg/hr.m2 ) for air flow parallel to the surface in case of constant drying rate in batch drying is related as hG = 0.0176G0.8. But when the flow of air perpendicular to the surface is encountered, this equation changes to ____________________?

   A. hG = 1.004G0.37
   B. 1.004G0.8
   C. hG = 0.0176G0.37
   D. 0.0176G1.37

2. In the design of a bag filter, the gas temperature is an important consideration, as it affects the___________________?

   A. Gas density
   B. Gas viscosity
   C. Fibre selection
   D. All A., B. & C.

3. The ratio of volumes of the mixed reactor to the plug flow reactor (for identical feed composition, flow rate, conversion, and for all positive reaction orders) is always ?

   A. 1
   B. < 1
   C. > 1
   D. Equal to the order of reaction

4. Poisson’s ratio of a material is the ratio of unit lateral strain to the unit axial elongation within its elastic limit. The value of Poisson’s ratio for structural and pressure vessel steel may be taken as ____________________?

   A. 0.01
   B. 0.3
   C. 0.75
   D. 0.95

5. The operating pressure drop range in a bag filter is about ______________ mm water gauge?

   A. 50-150
   B. 5-10
   C. 500-1500
   D. 1500-2500

6. In a bag filter, the pressure drop increases directly as the___________________?

   A. Density of the gas, but is independent of the viscosity of the gas
   B. Density of the gas and inversely as viscosity of the gas
   C. Viscosity of the gas and inversely as density of the gas
   D. None of these

7. For turbulent flow (NRe > 2100) of low viscosity fluid (μ > 20cp) in steel pipes, the optimum inside pipe diameter is given by(where, Q = fluid flow rate, ft3/sec, ρ = fluid density, lb/ft3 μ = fluid viscosity, centipoise Di = optimum inside pipe diameter, inches) ?

   A. Di, opt = 3.9 Q0.45 ρ0.13
   B. Di, opt = 3.9 Q0.45. μ0.95
   C. Di, opt = 4.7 Q0.36. μ3.2ρ0.13
   D. Di, opt = 3 Q0.36. μ0.88

8. Tube side pressure drop in a 1-2 heat exchanger (for turbulent flow of fluids through the tubes) is about __________ times, that in a 1-1 heat exchanger having the same size & number of tubes and operated at the same liquid flow rate ?

   A. 2
   B. ½
   C. 4
   D. 8

9. A single pass air heater is connected to a two pass unit. For the air flow rate and other conditions remaining the same, the film heat transfer co-efficient for air will vary in the ratio of_________________?

   A. 2
   B. 20.8
   C. 20.2
   D. None of these

10. In a shell and tube heat exchanger, the overall heat transfer co-efficient is proportional to the tube side (volumetric flow rate)0.8. This is valid, only when the ratio of the tube side film resistance to the total resistance is almost equal to____________________?

    A. ∞
    B. 1
    C. 20.8
    D. 2