NRe

. NPr

) (D/L) is called the __________ number

(A) Peclet

(B) Stanton

(C) Graetz

(D) None of these

1 Answer

Answer :

(C) Graetz

Related questions

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 : NGr × NPr ) is called the __________ number. (A) Graetz (B) Rayleigh (C) Nusselt (D) Stanton

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Description : (NRe . NSc ) is termed in mass transfer operation as the __________ number. (A) Stanton (B) Sherwood (C) Peclet (D) None of these

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Description : . (NSh /NRe .NSc ) is termed in mass transfer operation as the (A) Stanton number (B) Peclet number (C) Thermal diffusivity (D) Momentum diffusivity

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Description : The ratio of kinematic viscosity to thermal diffusivity is called the __________ number. (A) Peclet (B) Prandtl (C) Stanton (D) Nusselt

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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

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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

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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

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Description : Which of the following is not concerned with the heat transfer? (A) Brinkman number (B) Stanton number (C) Schmidt number (D) Peclet number

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Description : In a mixer, the quantity, (v. L/D) is termed as __________ number (where, v = longitudinal velocity of material, L = length of the mixer, D = diffusivity in axial mixing). (A) Weber (B) Peclet (C) Brinkman (D) Schmidt

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Description : The equation, (h.D/K) is called the __________ number. (A) Nusselt (B) Peclet (C) Rayleigh (D) Grashoff

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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

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Description : Asymptotic conditions is reached, when for a fluid flowing in laminar flow through a long tube (A) Exit-fluid temperature > wall temperature (B) Exit fluid temperature < wall temperature (C) Exit fluid temperature = wall temperature (D) Graetz number > 100

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Description : In natural convection heat transfer, the correlating parameter is the (A) Graetz number (B) Eckert number (C) Grashoff number (D) Bond number

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Description : The Graetz number is concerned with the (A) Mass transfer between a gas and a liquid (B) Absorption with chemical reaction (C) Heat transfer in turbulent flow (D) Heat transfer in laminar flow

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Description : The equation f -0.5 = 4.07 loge (NRe √f) -0.6 is called the __________. (A) Colebrook formula (B) Von-Karman equation (C) Fanning equation (D) None of these

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Description : A fluid (µ/ρ) = 0.01 cm2 /sec is moving at critical flow condition (NRe = 2100) through a pipe of dia 3 cms. Velocity of flow is __________ cm/sec. (A) 7 (B) 700 (C) 7000 (D) 630

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Description : The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are same for, NPr = NSc = __________ (A) 1 (B) 0.5 (C) 10 (D) 0

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Description : The equation, Nst = (f/2)/[1 + 5 (Npr - 1) √(f/2)], corresponds to __________ analogy. (A) Von-Karman (B) Reynolds (C) Colburn (D) Prandtl

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Description : Natural convection is characterised by (A) Grashoff number (B) Peclet number (C) Reynolds number (D) Prandtl number

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Description : Peclet number (Pe) is given by (A) Pe = Re.Pr (B) Pe = Re/Pr (C) Pe = Pr /Re (D) Pe = Nu.Re

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Description : For an ideal plug flow reactor, the value of Peclet number is (A) 0 (B) 1 (C) 10 (D) ∞

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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

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Description : 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

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Description : For a turbine agitated and baffled tank, operating at low Reynold's number (based on impeller diameter), the power number (Np ) varies with NRe as (A) Np ∝ NRe (B) Np ∝ √NRe (C) Np → constan (D) Np ∝ 1/NRe

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Description : The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe whose surface temperature remains constant is (A) 1.66 (B) 88.66 (C) 3.66 (D) Dependent on NRe only

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Description : The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe, where the wall heat flux is constant, is (A) 2.36 (B) 4.36 (C) 120.36 (D) Dependent on NRe only

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Description : Pick out the wrong statement. (A) The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are the same for NSc = NPr= 1 (B) 1 Nm3 of dry air is lighter ... ) The Lewis number of a mixture is unity, when the thermal diffusivity is equal to the mass diffusivity

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Description : For flow over a flat plate, the ratio of thermal boundary layer thickness, 'xt' and hydrodynamic boundary layer thickness 'x' is equal to (where, NPr = Prandtl number) (A) NPr (B) NPr 1/3 (C) NPr -1 (D) NPr -1/3

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Description : Heat transfer co-efficient (h) for a fluid flowing inside a clean pipe is given by h = 0.023 (K/D) (DVρ/µ) 0.8 (CP .µ/k) 0.4 . This is valid for the value of NRe equal to (A) < 2100 (B) 2100-4000 (C) > 4000 (D) > 10000

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Description : Friction factor for a hydraulically smooth pipe at NRe = 2100 is f1 . If the pipe is further smoothened (i.e., roughness is reduced), the friction factor at the same value of NRe , will (A) Increase (B) Decrease (C) Remain unchanged (D) Increase or decrease depending on the pipe material

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Description : For the free settling of a spherical particle through a fluid, the slope of, CD-log NRe , plot is (A) 1 (B) -1 (C) 0.5 (D) -0.5

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Description : f = 16/NRe , is valid for (A) Turbulent flow (B) Laminar flow through an open channel (C) Steady flow (D) None of these

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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

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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

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Description : The thermal boundary layer at NPr > 1 (A) Is thicker than hydrodynamic boundary layer (B) Is thinner than hydrodynamic boundary layer (C) And the hydrodynamic boundary layers are identical (D) Disappears

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Description : What led to lucretia mott and elizabeth cady Stanton to work together?

Last Answer : their outrage that women were refused full participation inbusiness meetings

Description : How did Abraham Lincoln meet his future secretary of war Edward Stanton?

Last Answer : In 1854 Abraham Lincoln was retained by Cyrus McCormick regarding a patent lawsuit. The case was originally to be tried in Illinois where Lincoln could practice law. Just before the case was set for ... Stanton conducted the patent case and in 1862, Stanton became the second Union secretary of war.