Description : Transition length for turbulent flow in smooth pipe is equal to __________ times the pipe diameter. (A) 0.5 (B) 5 (C) 50 (D) 500
Last Answer : (C) 50
Description : Pick out the correct statement pertaining to transition/ entrance length in fluid flow. (A) The length of entrance region of pipe, in which full development of fluid flow takes place such that velocity profile does not change ... pipe of diameter 'd' is equal to 50 D (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Transition from laminar flow to turbulent flow in fluid flow through a pipe does not depend upon the (A) Length of the pipe (B) Diameter of the pipe (C) Density of the fluid (D) Velocity of the fluid
Last Answer : (A) Length of the pipe
Description : Convective heat transfer co-efficient in case of fluid flowing in tubes is not affected by the tube length/diameter ratio, if the flow is in the __________ zone. (A) Laminar (B) Transition (C) Both 'a' & 'b' (D) Highly turbulent
Last Answer : (D) Highly turbulent
Description : In a fully turbulent flow (Re > 10 5 ) in a pipe of diameter 'd', for a constant pressure gradient, the dependence of volumetric flow rate of an incompressible fluid is (A) d (B) d 2 (C) d 2.5 (D) d
Last Answer : (C) d 2.5
Description : A fluid is flowing inside the inner tube of a double pipe heat exchanger with diameter 'd'. For a fixed mass flow rate, the tube side heat transfer coefficient for turbulent flow conditions is proportional to (A) d 0.8 (B) d -0.2 (C) d -1 (D) d -1.8
Last Answer : (B) d -0.2
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 : Calorific value of dry wood may be around __________ Kcal/kg. (A) 5 (B) 50 (C) 500 (D) 5000
Last Answer : (A) 5
Description : When the pipe Reynold's number is 6000, the flow is generally (A) Viscous (B) Laminar (C) Turbulent (D) Transition
Last Answer : (C) Turbulent
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 : For the Stoke's law to be valid in the case of a falling sphere in a fluid, the (A) Reynolds number (based on sphere diameter) should be < 1 (B) Flow around the sphere should be in turbulent region (C) Sphere must be metallic (D) Fluid density should be constant
Last Answer : (C) Sphere must be metallic
Description : The maximum discharge through a circular channel takes place, when the depth of the fluid flow is __________ times the pipe diameter. (A) 0.25 (B) 0.5 (C) 0.66 (D) 0.95
Last Answer : (D) 0.95
Description : At what value of Prandtl number, conduction is negligible in the turbulent core of a fluid flowing through a heated pipe? (A) 0.5 (B) < 0.5 (C) > 0.6 (D) < 0.1
Last Answer : (C) > 0.6
Description : Pick out the wrong statement pertaining to fluid flow. (A) The ratio of average velocity to the maximum velocity for turbulent flow of Newtonian fluid in circular pipes is 0.5 (B) The Newtonian ... at the centre of the pipe (C) Navier-Stokes equation is applicable to the analysis of viscous flows
Last Answer : (A) The ratio of average velocity to the maximum velocity for turbulent flow of Newtonian fluid in circular pipes is 0.5
Description : In case of turbulent flow of a Newtonian fluid in a straight pipe, the maximum velocity is equal to (where, Vavg = average fluid velocity) (A) Vavg (B) 1.2 Vavg (C) 1.5 Vavg (D) 1.8 Vavg
Last Answer : (B) 1.2 Vavg
Description : For turbulent flow of Newtonian fluid in a circular cross-section pipe, the ratio of maximum to average fluid velocity is (A) 0.5 (B) 1 (C) 0.66 (D) < 0.5
Last Answer : (B) 1
Description : At Pr > 1, conduction in an ordinary fluid flowing through a heated pipe is limited to the (A) Buffer zone (B) Turbulent core (C) Both (A) and (B) (D) Viscous sub-layer
Last Answer : (D) Viscous sub-layer
Description : Heat transfer by conduction in the turbulent core of a fluid flowing through a heated pipe is negligible, if the value of Prandtl number is (A) 0.2 (B) 0.4 (C) 0.6 (D) 0.8
Last Answer : (C) 0.6
Description : Pick out the wrong statement. (A) The form drag is dependent upon the occurrence of a wake (B) The shear stress at any given cross-section of a pipe for steady flow (either laminar or turbulent ... of viscosity (D) Existence of the boundary layer in fluid flow is because of viscosity of the fluid
Last Answer : (C) An ideal fluid is the one, which has negligible surface tension and obeys the Newton's law of viscosity
Description : The head loss in turbulent flow in pipe is proportional to(where, V = velocity of fluid through the pipe) (A) V 2 (B) 1/V 2 (C) 1/V (D) V
Last Answer : (A) V
Description : For turbulent flow of an incompressible fluid through a pipe, the flow rate ‘Q’ is proportional to (Δ P)n, where ΔP is the pressure drop. The value of exponent 'n' is (A) 1 (B) 0 (C) < 1 (D) > 1
Last Answer : (C) < 1
Description : essure drop (Δp) for a fluid flowing in turbulent flow through a pipe is a function of velocity (V) as (A) V1.8 (B) V-0.2 (C) V2.7 (D) V
Last Answer : (D) V
Description : The Sieder-Tate correlation for heat transfer in turbulent flow in pipe gives Nu α Re 0.8 , where, Nu is the Nusselt number and Re is the Reynolds number for the flow. Assuming that this relation is valid, the heat transfer co-efficient ... pipe diameter (D) as (A) D-1.8 (B) D-0.2 (C) D0.2 (D) D1.8
Last Answer : (B) D-0.2
Description : The head loss in turbulent flow in a pipe varies (A) Directly as the velocity (B) Inversely as the square of the velocity (C) Approximately as the square of the velocity (D) Inversely as the square of the diameter
Last Answer : (C) Approximately as the square of the velocity
Description : The head loss in turbulent flow in a pipe varies (A) As velocity (B) As (velocity) 2 (C) Inversely as the square of diameter
Last Answer : (B) As (velocity)
Last Answer : (C) Inversely as the square of diameter
Description : or Indian standard (IS) screens, the mesh number is equal to its aperture size expressed to the nearest deca-micron (0.01 mm). Aperture width of IS screen of mesh number 50 will be approximately __________ microns. (A) 5 (B) 50 (C) 500 (D) 5000
Last Answer : (C) 500
Description : From pollution control point of view, the maximum permissible concentration of sulphur dioxide in atmospheric air is about __________ ppm. (A) 5 (B) 50 (C) 500 (D) 5000
Description : Steam side heat transfer co-efficient in an evaporator is in the range of __________ kcal/hr.m2°C. (A) 10-50 (B) 100-500 (C) 1000-1500 (D) 5000-15000
Last Answer : (D) 5000-15000
Description : For laminar flow of Newtonian fluids through a circular pipe, for a given pressure drop and length & diameter of pipe, the velocity of fluid is proportional to (where, μ = fluid viscosity ) (A) μ (B) 1/μ (C) √μ (D) 1/√μ
Last Answer : (B) 1/μ
Description : The pressure drop per unit length for laminar flow of fluid through a long pipe is proportional to (where, A = cross-sectional area of the pipe & D = Diameter of the pipe) (A) A (B) D (C) 1/A (D) 1/A2
Last Answer : (C) 1/A
Description : Maximum heat transfer rate is obtained in __________ flow. (A) Laminar (B) Turbulent (C) Creeping (D) Transition region
Last Answer : (B) Turbulent
Description : Critical value of the __________ number governs the transition from laminar to turbulent flow in free convection heat transfer. (A) Grashoff (B) Reynolds (C) Both 'a' & 'b' (D) Prandtl & Grashoff
Last Answer : (D) Prandtl & Grashoff
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 : Pick out the wrong statement. (A) A fluid mass is free from shearing forces, when it is made to rotate with a uniform velocit (B) Newton's law of viscosity is not applicable to the ... types of bearings (D) Rise of water in capillary tubes reduces with the increasing diameter of capillary tubes
Last Answer : (B) Newton's law of viscosity is not applicable to the turbulent flow of fluid with linear velocity distribution
Description : The fluid velocity varies as the cube of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop for __________ fluid. (A) Newtonian (B) Pseudo-plastic (C) Dilatent (D) Bingham plastic
Last Answer : (B) Pseudo-plastic
Description : The fluid velocity varies as the square of the cylindrical pipe diameter, in case of steady state laminar flow at constant pressure drop, for __________ fluid. (A) Newtonian (B) Dilatant (C) Pseudo-plastic (D) Non-Newtonian
Last Answer : (A) Newtonian
Description : The fluid velocity varies as the square root of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop of __________ fluid. (A) Dilatent (B) Pseudo-plastic (C) Bingham plastic (D) Newtonian
Last Answer : (A) Dilatent
Description : To pump water from a water reservoir 3 m deep and maximum water level at 135 m, a pump is installed to lift water up to R.L. 175 m at a constant rate of 36,00,000 litres per hour. If the length of the ... the water horse power of the pump is (A) 400 (B) 450 (C) 500 (D) 600
Last Answer : (D) 600
Description : For turbulent flow in smooth circular pipe, the velocity distribution is a function of the distance 'd' measured from the wall of the pipe and the friction velocity 'v', and it follows a __________ relationship. (A) Logarithmic (B) Linear (C) Hyperbolic (D) Parabolic
Last Answer : (A) Logarithmic
Description : Navier-Stokes equation is useful in the analysis of __________ fluid flow problems. (A) Non-viscous (B) Viscous (C) Turbulent (D) Rotational
Last Answer : (B) Viscous
Description : Transition from laminar flow to turbulent flow is aided by the (A) Surface roughness and curvature (i.e. sharp corners) (B) Vibration (C) Pressure gradient and the compressibility of the flowing medium (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : Transition from laminar to turbulent zone in free convection heat transfer is governed by the critical value of (A) Grashoff number (B) Grashoff number & Reynolds number (C) Reynolds number (D) Grashoff number & Prandtl number
Last Answer : Option D
Description : For a small scale toy factory, the fixed cost per month is Rs. 5000/-. The variable cost per toy is Rs. 20 and sales price is Rs. 30 per toy. The break even production per month will be __________ toys. (A) 250 (B) 500 (C) 1000 (D) 3000
Last Answer : (B) 500
Description : Pressure gradient in the pipe flow is influenced by the (A) Diameter of pipe (B) Velocity of the fluid (C) Density & viscosity of the fluid (D) All (A), (B) and (C)
Description : Location of vena-contracta in an orificemeter does not depend upon the (A) Type of orifice (B) Density, viscosity & compressibility of the fluid (C) Ratio of pipe diameter to orifice diameter (D) Pipe roughness
Last Answer : (A) Type of orifice
Description : Critical velocity in a pipe flow (A) Increases as fluid viscosity increases (B) Increases as pipe diameter increases (C) Independent of fluid density (D) None of these
Last Answer : (B) Increases as pipe diameter increases
Description : For a given fluid, as the pipe diameter increases, the pumping cost (A) Decreases (B) Increases (C) Remains the same (D) May increase or decrease, depending upon whether the fluid is Newtonian or non-Newtonian
Last Answer : (A) Decreases
Description : Optimum economic pipe diameter for fluid is determined by the (A) Viscosity of the fluid (B) Density of the fluid (C) Total cost considerations (pumping cost plus fixed cost of the pipe) (D) None of these
Last Answer : (C) Total cost considerations (pumping cost plus fixed cost of the pipe)
Description : Reynolds number of a fluid flowing in a circular pipe is 10,000. What will be the Reynolds number when the fluid velocity is decreased by 30% & the pipe diameter is increased by 30%? (A) 9,100 (B) 13,000 (C) 7,000 (D) 2,550
Last Answer : (A) 9,100