Description : The specific cake resistance for incompressible sludges is (where ΔP = pressure drop over cake) (A) ∝ ΔP (B) ∝ 1/ ΔP (C) ∝ √ΔP (D) Independent of ΔP
Last Answer : (D) Independent of ΔP
Description : With increase in the pressure drop across the cake, the specific cake resistance for the compressible sludge (A) Increases (B) Decreases (C) Remains constant (D) Increases linearly
Last Answer : (A) Increases
Description : Pick out the wrong statement. (A) For the compressible cake, voidage & the specific resistance of the cake can be assumed to be constant (B) Cake resistance is independent of the pressure ... Crushing of explosive materials are done by employing dry-grinding (D) Gyratory crusher is a coarse crusher
Last Answer : (B) Cake resistance is independent of the pressure drop
Description : A compressible cake has the (A) Maximum porosity at the upstream side (B) Maximum porosity at the filter medium (C) Same porosity throughout the cake thickness (D) None of these
Last Answer : (A) Maximum porosity at the upstream side
Description : The porosity of a compressible cake is (A) Minimum at the filter medium (B) Minimum at the upstream face (C) Maximum at the filter medium (D) Same throughout the thickness of cake
Last Answer : (A) Minimum at the filter medium
Description : The basic filtration equation is given as dt/dV = (µ/A ∆P). [(α .CV/A) + Rm], where, V is volume of the filtrate; A is the filtration area, a is specific cake resistance, μ is viscosity of ... produced? Neglect filter medium resistance, Rm; assume incompressible cake. (A) 10 (B) 20 (C) 25 (D) 30
Last Answer : (B) 20
Description : For the same heat load and mass flow rate in the tube side of a shell and tube heat exchanger, one may use multipass on the tube side, because it (A) Decreases the pressure drop (B) ... the outlet temperature of cooling medium (C) Increases the overall heat transfer coefficient (D) None of these
Last Answer : (C) Increases the overall heat transfer coefficient
Description : Range of compressibility co-efficient of the commercial compressible cake obtained in filtration operation is (A) 0.01 to 0.1 (B) 0.1 to 0.3 (C) 0.2 to 0.8 (D) 0.2 to 0.4
Last Answer : (C) 0.2 to 0.8
Description : Compressibility co-efficient for an absolutely compressible cake is (A) 0 (B) 1 (C) 0 to 1 (D) ∞
Last Answer : (B) 1
Description : A straight line is obtained on plotting reciprocal of filtration rate vs. the volume of filtrate for __________ flow of filtrate. (A) Compressible cakes and laminar (B) Incompressible cake and laminar (C) Compressible cake and turbulent (D) Incompressible cake and turbulent
Last Answer : (B) Incompressible cake and laminar
Description : Cake resistance is (A) Important in the beginning of filtration (B) Decreased with the time of filtration (C) Independent of pressure drop (D) None of these
Last Answer : (D) None of these
Description : Filtration rate does not depend upon the (A) Pressure drop & area of filtering surface (B) Resistance of the cake & the septum (C) Properties of the cake & the filtrate (D) None of these
Description : Filter aids like asbestos, kieselguhr, diatomaceous earth etc. are used to increase the porosity of the final filter cake & reducing the cake resistance during filtration. Filter aid is (A) Added to the feed slurry (B) Pre ... the cake by dissolving solids or by burning it off (D) All 'a', 'b' & 'c'
Last Answer : (D) All 'a', 'b' & 'c'
Description : During the washing of cake (A) All the resistances are constant (B) Filter medium resistance increases (C) Filter medium resistance decreases (D) Cake resistance decreases
Last Answer : (A) All the resistances are constant
Description : The controlling resistance in a rotary drum vacuum filter is the __________ resistance. (A) Piping (B) Cake (C) Filter medium (D) None of these
Last Answer : (B) Cake
Description : During filtration operation, the filtrate encounters the resistance of the (A) Filter medium (B) Cake (C) Channel carrying the slurry to the upstream side of the cake and filtrate away from the filter medium (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Filtrate flow rate in case of a rotary drum vacuum filter (in which Rm < < Rc ) is proportional to __________ and the cycle time (where, μ = filtrate viscosity Rm = filter medium resistance Rc = cake resistance). (A) √μ (B) 1/√μ (C) 1/μ (D) 1/μ
Last Answer : (B) 1/√μ
Description : Priming in a distillation column (A) Results from very low gas velocity (B) Is desirable from point efficiency consideration (C) Is characterised by the presence of foam throughout the space between trays (D) Reduces the overall pressure drop
Last Answer : (C) Is characterised by the presence of foam throughout the space between trays
Description : Very tall packed towers are divided into series of beds to (A) Reduce the overall pressure drop (B) Avoid channelling (C) Reduce liquid hold-up (D) Avoid flooding
Last Answer : (B) Avoid channelling
Description : The main reason for dividing a tall packed tower into series of small towers is to (A) Minimise the overall pressure drop (B) Avoid flooding (C) Reduce liquid hold up (D) Avoid channelling
Last Answer : (D) Avoid channelling
Description : Which of the following option is incorrect about the sludges? a) Sludges are soft, loose and slimy precipitate b) They are non-adherent deposits and can be easily removed c) Formed generally at heated portions of the boiler d) Can be removed by blow down operation
Last Answer : c) Formed generally at heated portions of the boiler
Description : If the precipitate formed is soft, loose and slimy, these are __________ and if the precipitate is hard and adhering on the inner wall, it is called _____________ a) Sludges, scale b) Scale, sludges c) Sludges, rodent d) Scale, rodent
Last Answer : a) Sludges, scale
Description : Filter aid is used to (A) Increase the rate of filtration (B) Decrease the pressure drop (C) Increase the porosity of the cake (D) Act as a support base for the septum
Last Answer : (C) Increase the porosity of the cake
Description : A centrifugal filtration unit operating at a rotational speed of w has inner surface of the liquid (density ρL) located at a radial distance R from the axis of rotation. The thickness of the liquid film is δ and no cake is formed. The ... . ρL (C) ½w 2 . δρL (2R + δ) (D) ½w 2 . R . ρL(R + 2δ)
Last Answer : (C) ½w 2 . δρL (2R + δ)
Description : 17. The specific weight of compressible fluids does not remain constant. A) True B) False
Last Answer : A
Description : The unit of specific cake resistance is (A) gm/cm2 (B) cm/gm (C) cm/gm2 (D) gm/gm
Last Answer : (A) gm/cm2 (
Description : Filtration rate through a filter cake is proportional to (where, S = filtering surface R = specific cake resistance μ = viscosity of the filtrate) (A) S (B) 1/R (C) 1/μ (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : . In filtration, the use of 'filter aid' helps in (A) Reducing the filtration pressure (B) Accelerating the rate of filtration (C) Deplugging the filter medium (D) Enhancing the cake porosity in case of a dense impermeable cake
Last Answer : (C) Deplugging the filter medium
Description : The bulk modulus of elasticity (A) Has the dimensions of 1/pressure (B) Increases with pressure (C) Is large when fluid is more compressible (D) Is independent of pressure and viscosity
Last Answer : Answer: Option B
Description : Which one of the following statements is correct ? a) For water at 100o Celsius at sea level, the vapour pressure is equal to atmospheric pressure b) Surface energy (or tension) is caused by ... it both in static and in dynamic conditions d) Air is 50,000 times more compressible than water
Last Answer : c) Viscosity of a fluid is the property exhibited by it both in static and in dynamic conditions
Description : The cake resistance increases steadily with the time of filtration in a plate and frame filter employing constant __________ filtration. (A) Rate (B) Pressure (C) Both (A) & (B) (D) Neither (A) nor (B
Last Answer : (C) Both (A) & (B)
Description : Experiments were conducted to determine the flux of a species A in a stagnant medium across a gas-liquid interface. The overall mass transfer coefficient based on the liquid side for dilute systems for the above was estimated to be 4 ... -4 (C) 5.6 10 -3 (D) 8.5 10 -3
Last Answer : (B) 8.5 × 10 -4
Description : In an operating distillation column, the (A) Vapors and liquids are at their dew point and bubble point respectively (B) Driving force for the liquid flow is its specific weight (C) Driving force for ... bottom to the top of the column (D) Highest temperature is encountered at the top of the column
Last Answer : (C) Driving force for the vapor flow is the pressure drop, as the pressure decreases gradually from the bottom to the top of the column
Description : he pressure drop per unit length of pipe incurred by a fluid 'X' flowing through pipe is Δp. If another fluid 'Y' having both the specific gravity & density just double of that of fluid 'X', flows through the same pipe ... then the pressure drop in this case will be (A) Δp (B) 2Δp (C) Δp 2 (D) Δp/2
Last Answer : (B) 2Δp
Description : Reynolds number for water flow through a tube of I.D. 5 cm is 1500. If a liquid of 5 centipoise viscosity and 0.8 specific gravity flows in the same pipe at the same velocity, then the pressure drop will (A) Increase (B) Decrease (C) Remain same (D) Data insufficient to predict pressure drop
Last Answer : (A) Increase
Description : Bernoulli's equation for fluid flow is derived following certain assumptions. Out of the assumptions listed below, which set of assumptions is used in derivation of Bernoulli's equation? A. Fluid flow is frictionless & irrotational. B. Fluid flow is ... A, C, D (B) B, D, E (C) A, B, E (D) A, D, E
Last Answer : (C) A, B, E
Description : If in a flow field, between any two points, then the flow must be (A) Steady, incompressible, irrotational (B) Steady, compressible, irrotational (C) Steady, compressible and along a streamline
Last Answer : (A) Steady, incompressible, irrotational
Description : Pick out the wrong statement. (A) The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). ∆p (B) In the equation, T. gc = k. ... to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids
Last Answer : (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids
Description : The energy equation, E + (p/ρ) + (V 2 /2g) + gZ = constant (E = internal energy/mass), is applicable to (A) Perfect gases only (B) Isothermal flow of gases (C) Adiabatic unsteady flow of gases (D) All compressible fluids
Last Answer : (D) All compressible fluids
Description : The Mach number for hypersonic flow of compressible fluid is (A) 1 (B) > 1 (C) > 4 (D) < 2
Last Answer : (C) > 4
Description : A fluid element has a velocity V = -y 2 . xi + 2yx 2 . j. The motion at (x, y) = (1/√2, 1) is (A) Rotational and incompressible (B) Rotational and compressible (C) Irrotational and compressible (D) Irrotational and incompressible
Last Answer : (B) Rotational and compressible
Description : Potential flow is the flow of (A) Compressible fluids with shear (B) Compressible fluids with no shear (C) Incompressible fluids with shear (D) Incompressible fluids with no shear
Last Answer : (D) Incompressible fluids with no shear
Description : Fanning friction factor equation applies to the __________ fluid flow. (A) Non-isothermal condition of (B) Compressible (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (D) Neither (A) nor (B)
Description : In electronic fuel injection, there is improvement in the _____________ efficiency due to comparatively less resistance in the intake manifolds which will cause less pressure losses. a) mechanical b) volumetric c) overall d) none of the mentioned
Last Answer : Answer: b Explanation: In electronic fuel injection, there is improvement only in the volumetric efficiency due to comparatively less resistance in the intake manifolds which will cause less pressure losses and no other efficiencies are hindered.
Description : Is it a bad idea to drop peanut butter cups or other small candies into a cake you're going to stack?
Last Answer : We put together multilayer wedding cakes, by using dowel rods in the cake to support the weight, and each layer on its own cardboard separator.
Description : Aluminium when adopted as a conductor material in ______ transformers, decreases the overall cost of the transformer (a) small size (b) medium size (c) large size (d) any of the above size
Last Answer : (a) small size
Description : 1000 Kg of liquid at 30°C in a well stirred vessel has to be heated to 120°C, using immersed coils carrying condensing steam at 150°C. The area of the steam coils is 1.2 m2 and the overall heat transfer co-efficient to the ... will be (A) 15 min (B) 22 min (C) 44 min (D) 51 min
Last Answer : (D) 51 min
Description : Out of the following four assumptions used in the derivation of theequation for LMTD [LMTD = (∆t1 - ∆t2 )/ln(∆t1 /∆t2 )], which one is subject to the largest deviation in practice ? (A) Constant ... (B) Constant rate of fluid flow (C) Constant specific heat (D) No partial phase change in the system
Last Answer : (B) Constant rate of fluid flow
Description : Overall thermal resistance for conductive heat transfer through a series of flat resistances is equal to the (A) Maximum resistance in the series (B) Sum of all resistances (C) Average of all resistances (D) Minimum resistance presents in the series
Last Answer : (B) Sum of all resistances
Description : If h1 = inner film co-efficient and /h2 = outer film co-efficient, then the overall heat transfer co-efficient is (A) Always less than h1 (B) Always between h1 and h2 (C) Always higher than h2 (D) Dependent on metal resistance
Last Answer : (B) Always between h1 and h2