Reynold's analogy states that (where, St = Stanton number f = friction
factor)
(A) St = f/2
(B) St = f/4
(C) St = 4f
(D) St = f
1/2
Description : According to Reynolds analogy, Stanton number is equal to (where, f = Fanning friction factor) (A) 2f (B) f (C) f/2 (D) f/4
Last Answer : (C) f/2
Description : Reynold's analogy states that (A) Nst α f (B) Nst α NRe (C) NNu α f (D) NRe α f
Last Answer : (A) Nst α f
Description : Reduction in vibration amplitude after one complete cycle of single degree free vibration with dry friction damping is_____, if where F"= frictional force between mass and surface and k =stiffness of the system. a)4F/k a b) 2f/K C) 3F/k D)8F/k
Last Answer : a)4F/k
Description : The equation, Nst = (f/2)/[1 + 5 (Npr - 1) √(f/2)], corresponds to __________ analogy. (A) Von-Karman (B) Reynolds (C) Colburn (D) Prandtl
Last Answer : (D) Prandtl
Description : The equation, (NSt × N2/3 Pr ) = f/2, is the __________ analogy. (A) Colburn (B) Reynolds (C) Prandtl (D) None of these
Last Answer : (A) Colburn
Description : The equation, Nst = f/2, is the __________ analogy. (A) Colburn (B) Reynolds (C) Prandtl (D) None o
Last Answer : (B) Reynolds
Description : The friction factor for turbulent flow in a hydraulically smooth pipe (A) Depends only on Reynolds number (B) Does not depend on Reynolds number (C) Depends on the roughness (D) None of these
Last Answer : (A) Depends only on Reynolds number
Description : The friction factor is (A) Always inversely proportional to the Reynolds number (B) Not dimensionless (C) Not dependent on the roughness of the pipe (D) None of these
Last Answer : (D) None of these
Description : Pick out the correct statement. (A) Fanning friction factor is inversely proportional to Reynolds number always (B) The property of a randomly packed bed (with raschig rings) is given by the ratio of the ... the ratio of the speed of the fluid to that of sound in the fluid under conditions of flow
Last Answer : (D) Mach number is given by the ratio of the speed of the fluid to that of sound in the fluid under conditions of flow
Description : In turbulent flow, a rough pipe has the same friction factor as a smooth pipe (A) In the zone of complete turbulence (B) When the roughness projections are much smaller than the thickness of ... ) Everywhere in the transition zone (D) When the friction factor is independent of the Reynold's number
Last Answer : (B) When the roughness projections are much smaller than the thickness of the laminar film
Description : Which of the following quantities are computed by using the hydraulic radius for non-circular ducts? (A) Velocity and relative roughness (B) Head loss and velocity (C) Reynold number, relative roughness and head loss (D) Reynolds number and friction factor
Last Answer : (C) Reynold number, relative roughness and head loss
Description : A pipe is defined as 'hydraulically smooth', if the friction factor (A) Is not a function of Reynolds number (B) For a given Reynolds number remains constant even on further smoothening of the pipe (C) Is zero irrespective of the Reynolds number (D) None of these
Last Answer : (B) For a given Reynolds number remains constant even on further smoothening of the pipe
Description : Pick out the wrong statement: (A) Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer (B) Blowers develop a maximum pressure of 2 atmospheres ( ... factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number
Last Answer : (C) Friction losses in pipe fittings are generally expressed in terms of velocity heads
Description : For a given Reynolds number, in a hydraulically smooth pipe, further smoothening __________ the friction factor. (A) Brings about no further reduction of (B) Increases (C) Decreases (D) None of these
Last Answer : (A) Brings about no further reduction of
Description : Fanning friction factor for laminar flow of fluid in a circular pipe is (A) Not a function of the roughness of pipe wall (B) Inversely proportional to Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : All analogy equations connecting friction factor and heat transfer coefficient apply only to (A) Wall or skin friction (B) Form friction (C) Both (A) and (B) (D) Turbulent flow
Last Answer : (A) Wall or skin friction
Description : Pick out the wrong statement. (A) The Reynolds analogy for mass transfer is given by Lewis relation and is applicable, when Schmidt number is one (B) Sherwood number for flow in pipes can be expressed ... flux of a component A in binary mixture of A and B is given by - Dab'.dCA/dz
Last Answer : (C) According to film theory for equimolar counter diffusion, the mass transfer coefficient is given by DAB(B)P - 3, Q - 2
Description : Pick out the wrong statement pertaining to the analogy between equations of heat and mass transfer operations. (A) Sherwood number in mass transfer is analogous to Nusselt number in heat transfer ... heat transfer (D) Reynolds number remains the same in both heat and mass transfer
Last Answer : (C) Reynolds number in mass transfer is analogous to Grashoff number in heat transfer
Description : Prandtl and Reynolds analogy are same, when Prandtl number is (A) 0.5 (B) 1 (C) > 2 (D) 1.5
Last Answer : (B) 1
Description : What is 3f plus f plus 4f equal?
Last Answer : 7f
Description : Two bodies kept at a certain distance feel a gravitational force F to each other. If the distance between them is made double the former distance, the force will be - (1) 2F (2) F/2 (3) 4F (4) F/4
Last Answer : (4) F/4
Description : In coulomb damping, the amplitude of motion in each cycle is reduced by A. F/K B. 2F/K C. 4F/K D. F/4K
Last Answer : C. 4F/K
Description : Pick out the wrong statement. (A) Fluid movement under the influence of buoyant forces resulting from change in density takes place in case of natural convection (B) The ratio NNu /NRe . Npr is ... convection to that by conduction (D) The Colburn jH factor for heat transfer is given by Nst Npr
Last Answer : (D) The Colburn jH factor for heat transfer is given by Nst Npr
Description : In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said ... co-efficient for flows at equal Reynold number (D) All (A), (B) & (C)
Last Answer : (C) Friction co-efficient for flows at equal Reynold number
Description : . In case of turbulent flow of fluid through a circular pipe, the (A) Mean flow velocity is about 0.5 times the maximum velocity (B) Velocity profile becomes flatter and flatter with ... , shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more
Last Answer : (D) Skin friction drag, shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more
Description : Analogies are comparisons. Complete each analogy below. Here is an example: Ear is to hearing as eye is to? Sight.1. Cardinals is to St. Louis as Dodger is to?2. A.M. is to before noon as P.M. is to ... 8 is to?4. Tear is to tore as see is to?5. Springfield is to Illinois as Austin is to? -Riddles
Last Answer : 1. Los Angeles 2. Afternoon 3. Octagon 4. Saw 5. Texas
Description : The equation relating friction factor to Reynold number, f -0.5 = 4 loge (NRe /√f) -0.4 , is called the __________ equation. (A) Nikuradse (B) Von-Karman
Last Answer : (B) Ergun's
Description : The viscous friction co-efficient, in force-voltage analogy, is analogous to?
Last Answer : The viscous friction co-efficient, in force-voltage analogy, is analogous to resistance.
Description : Colebrook equation for friction factor in turbulent flow is given by, f -0.5 = -4 loge [(ε/D) + (1.26/NRe √F). It reduces to Nikuradse equation for a value of (ϵ/D) equal to (A) 0 (B) 1 (C) ∞ (D) 0.5
Description : What is the value of Fanning friction factor f ' for smooth pipe at NRe = 10 6 approximately? (A) 0.003 (B) 0.01 (C) 0.1 (D) 0.3
Last Answer : (A) 0.003
Description : Fanning equation is given by (∆P/ρ) = 4f (L/D) (v 2 /2gc ). It is applicable to __________ region flow. (A) Transition (B) Laminar (C) Turbulent (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : According to Chilton-Colburn analogy for mass transfer, NSt .NSc 2/3 is equal to (A) f (B) f/2 (C) 2f (D) 1/f
Last Answer : (B) f/2
Description : JD factor for mass transfer is a function of Reynolds number. Mass transfer by molecular diffusion from a single drop to surrounding still air is given by (A) Nsh = 2 (B) Nst = 2 (C) Nsc = 2 (D) None of these
Last Answer : (A) Nsh = 2
Description : jH factor for heat transfer is not a function of the __________ number. (A) Reynolds (B) Nusselt (C) Grashoff (D) Both (B) & (C)
Last Answer : (D) Both (B) & (C)
Description : jH factor for heat transfer depends upon the __________ number. (A) Biot (B) Nusselt (C) Reynolds (D) Prandtl
Last Answer : (C) Reynolds
Description : Froude number is not a factor (A) For Reynolds number greater than 300 (B) When there is no vortex formation (C) For unbaffled tank (D) None of these
Last Answer : (B) When there is no vortex formation
Description : Corresponding to Prandtl number in heat transfer, the dimensionless group in mass transfer is the __________ number. (A) Schmidt (B) Sherwood (C) Peclet (D) Stanton
Last Answer : (A) Schmidt
Description : . (NSh /NRe .NSc ) is termed in mass transfer operation as the (A) Stanton number (B) Peclet number (C) Thermal diffusivity (D) Momentum diffusivity
Last Answer : (A) Stanton number
Description : Corresponding to Nusselt number in heat transfer, the dimensionless group in mass transfer is the __________ number. (A) Sherwood (B) Schmidt (C) Peclet (D) Stanton
Last Answer : (A) Sherwood
Description : __________ number indicates the ratio of the rates of the heat and mass transfer incase of a cooling tower. (A) Sherwood (B) Stanton (C) Lewis (D) Peclet
Last Answer : (C) Lewis
Description : (NRe . NSc ) is termed in mass transfer operation as the __________ number. (A) Stanton (B) Sherwood (C) Peclet (D) None of these
Last Answer : (C) Peclet
Description : NSc /NPr is called the (A) Psychrometric ratio (B) Lewis number (C) Sherwood number (D) Stanton number
Last Answer : (B) Lewis number
Description : NRe . NPr ) (D/L) is called the __________ number (A) Peclet (B) Stanton (C) Graetz (D) None of these
Last Answer : (C) Graetz
Description : Which of the following is not concerned with the heat transfer? (A) Brinkman number (B) Stanton number (C) Schmidt number (D) Peclet number
Last Answer : (C) Schmidt number
Description : A measure of the extent to which viscous heating is important relative to the heat flow resulting from the impressed temperature difference is represented by the __________ number. (A) Condensation (B) Grashoff (C) Stanton (D) Brinkman
Last Answer : (D) Brinkman
Description : The ratio of momentum diffusivity to thermal diffusivity is the __________ number. (A) Prandtl (B) Nusselt (C) Stanton (D) Grashoff
Last Answer : (A) Prandtl
Description : The ratio of kinematic viscosity to thermal diffusivity is called the __________ number. (A) Peclet (B) Prandtl (C) Stanton (D) Nusselt
Last Answer : (B) Prandtl
Description : The dimensionless group in mass transfer that is equivalent to Prandtl number in heat transfer is (A) Nusselt number (B) Sherwood number (C) Schmidt number (D) Stanton numbe
Description : Nusselt number is a function of Prandtl number and __________ number of fluid in natural convection heat transfer. (A) Grashoff (B) Biot (C) Stanton
Last Answer : (A) Grashoff