Recuperated will be more efficient if the flow path of hot and cold fluids is in: a) Co-current mode b) Counter current mode c) Cross current mode d) Cone of the above

Recuperated will be more efficient if the flow path of hot and cold fluids is in:
a) Co-current mode b) Counter current mode
c) Cross current mode d) Cone of the above
by

1 Answer

Answer :

Counter current mode
by

Related questions

Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for counter flow and parallel flow can be theoretically same when any one of the fluids (hot or cold fluid) passes through the heat exchanger at constant temperature (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs (D) Phase change in case of a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature

Description : Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for ... a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature

Last Answer : (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs

Parallel straight line pattern of temperature distribution for both hot and cold fluids is observed in case of heat exchanger of the type (A) Parallel flow with equal heat capacities (B) Counter flow with equal heat capacities (C) Counter flow with unequal heat capacities (D) Parallel flow with unequal heat capacities

Description : Parallel straight line pattern of temperature distribution for both hot and cold fluids is observed in case of heat exchanger of the type (A) Parallel flow with equal heat capacities (B) Counter ... (C) Counter flow with unequal heat capacities (D) Parallel flow with unequal heat capacities

Last Answer : (B) Counter flow with equal heat capacities

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. (du/dy) n the value of 'n' for pseudoplastic and Dilatant fluid are < 1 and >1 respectively (C) Shear stress for Newtonian fluid is proportional to the rate of shear in the direction perpendicular to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids

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

The major limitation of metallic recuperated is ------- a) Limitation of handling COx, NOx etc. b) Limitation of reduced life for handling temperature more than 1000 oC c) Manufacturing difficulty of the required design d) None of the above

Description : The major limitation of metallic recuperated is ------- a) Limitation of handling COx, NOx etc. b) Limitation of reduced life for handling temperature more than 1000 oC c) Manufacturing difficulty of the required design d) None of the above

Last Answer : Limitation of reduced life for handling temperature more than 1000 oC

In a parallel flow heat exchanger, if the outlet temperature of hot and cold fluids are the same, then the log mean temperature difference (LMTD) is (A) Minimum (B) Maximum (C) Zero (D) Infinity

Description : In a parallel flow heat exchanger, if the outlet temperature of hot and cold fluids are the same, then the log mean temperature difference (LMTD) is (A) Minimum (B) Maximum (C) Zero (D) Infinity

Last Answer : (C) Zero

Recuperated is used mainly as a waste heat recovery system in a ____. a) Boiler b) Billet Reheating Furnace c) Compressor d) None of the above

Description : Recuperated is used mainly as a waste heat recovery system in a ____. a) Boiler b) Billet Reheating Furnace c) Compressor d) None of the above

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Which type of cooling towers operate through a chimney or stack ___ a. Cross flow b. Counter flow c. Hyperbolic d. All of above

Description : Which type of cooling towers operate through a chimney or stack ___ a. Cross flow b. Counter flow c. Hyperbolic d. All of above

Last Answer : Hyperbolic

. ______ type of cooling towers are structurally strong. a. Counter flow towers b. Hyperbolic towers c. Cross flow towers d. None of the above

Description : . ______ type of cooling towers are structurally strong. a. Counter flow towers b. Hyperbolic towers c. Cross flow towers d. None of the above

Last Answer : Hyperbolic towers

A 2-4 heat exchanger involves (A) Only counter-flow of fluids (B) Only parallel-flow of fluids (C) Both counter and parallel-flow of the fluids (D) Smaller pressure drop compared to 1-2 exchanger

Description : A 2-4 heat exchanger involves (A) Only counter-flow of fluids (B) Only parallel-flow of fluids (C) Both counter and parallel-flow of the fluids (D) Smaller pressure drop compared to 1-2 exchanger

Last Answer : (C) Both counter and parallel-flow of the fluids

LMTD for evaporators & condensers for a given terminal parameters & set of conditions for counter-flow is equal to that for parallel flow. In such heat exchangers, with one of the fluids condensing or evaporating, the surface area required is the least in the __________ flow. (A) Parallel (B) Mixed (C) Counter flow (D) Same in either 'a', b' or 'c'

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Last Answer : (D) Same in either 'a', b' or 'c'

Extremely large or small volumes of fluids are generally best routed through the shell side of a shell and tube heat exchanger, because of the (A) Less corrosion problems (B) Flexibility possible in the baffle arrangement (C) Low pressure drop (D) High heat transfer co-efficient

Description : Extremely large or small volumes of fluids are generally best routed through the shell side of a shell and tube heat exchanger, because of the (A) Less corrosion problems (B) Flexibility possible in the baffle arrangement (C) Low pressure drop (D) High heat transfer co-efficient

Last Answer : (B) Flexibility possible in the baffle arrangement

According to first law of thermodynamics  (a) mass and energy are mutually convertible  (b) Carnot engine is most efficient  (c) heat and work are mutually convertible  (d) mass and light are mutually convertible  (e) heat flows from hot substance to cold substance.

Description : According to first law of thermodynamics  (a) mass and energy are mutually convertible  (b) Carnot engine is most efficient  (c) heat and work are mutually convertible  (d) mass and light are mutually convertible  (e) heat flows from hot substance to cold substance.

Last Answer : Answer : c

LMTD for counter-flow and parallel flow heat exchanger will be the same, when the (A) Cold fluid is heated to a certain temperature by condensing steam (isothermal fluid) (B) Outlet temperature of both the hot and cold fluid are same (C) Outlet temperature of hot fluid is less than the outlet temperature of the cold fluid (D) None of these

Description : LMTD for counter-flow and parallel flow heat exchanger will be the same, when the (A) Cold fluid is heated to a certain temperature by condensing steam (isothermal fluid) (B) Outlet temperature of ... temperature of hot fluid is less than the outlet temperature of the cold fluid (D) None of these

Last Answer : (A) Cold fluid is heated to a certain temperature by condensing steam (isothermal fluid)

In a counter flow heat exchanger, hot fluid enters at 170°C & leaves at 150°C, while the cold fluid enters at 50°C & leaves at 70°C. The arithmetic mean temperature difference in this case is __________ °C. (A) 20 (B) 60 (C) 120 (D) ∞

Description : In a counter flow heat exchanger, hot fluid enters at 170°C & leaves at 150°C, while the cold fluid enters at 50°C & leaves at 70°C. The arithmetic mean temperature difference in this case is __________ °C. (A) 20 (B) 60 (C) 120 (D) ∞

Last Answer : (D) ∞

Which one of the following statements is incorrect? (a) The principle of countercurrent flow facilitates efficient respiration in gills of fishes. (b) The residual air in lungs slightly decreases the efficiency of respiration in mammals. (c) The presence of non-respiratory air sacs, increases the efficiency of respiration in birds. (d) In insects, circulating body fluids serve to distribute oxygen to tissues.

Description : Which one of the following statements is incorrect? (a) The principle of countercurrent flow facilitates efficient respiration in gills of fishes. (b) The residual air in lungs slightly decreases the ... in birds. (d) In insects, circulating body fluids serve to distribute oxygen to tissues.

Last Answer : (b) The residual air in lungs slightly decreases the efficiency of respiration in mammals.

Baffles in the shell side of a shell and tube heat exchanger (A) Increase the cross-section of the shell side liquid (B) Force the liquid to flow parallel to the bank (C) Increase the shell side heat transfer co-efficient (D) Decrease the shell side heat transfer co-efficient

Description : Baffles in the shell side of a shell and tube heat exchanger (A) Increase the cross-section of the shell side liquid (B) Force the liquid to flow parallel to the bank (C) Increase the shell side heat transfer co-efficient (D) Decrease the shell side heat transfer co-efficient

Last Answer : (C) Increase the shell side heat transfer co-efficient

Radiator of an automobile engine is a __________ type of heat exchanger. (A) Co-current (B) Cross-current (C) Counter-current (D) Direct contact

Description : Radiator of an automobile engine is a __________ type of heat exchanger. (A) Co-current (B) Cross-current (C) Counter-current (D) Direct contact

Last Answer : (D) Direct contact

In a 1-1 concurrent heat exchanger, if the tube side fluid outlet temperature is equal to the shell side fluid outlet temperature, then the LMTD is (A) ∞ (B) 0 (C) Equal to the difference between hot and cold fluids inlet temperature (D) Equal to the difference between hot fluid inlet temperature and cold fluid outlet temperature

Description : In a 1-1 concurrent heat exchanger, if the tube side fluid outlet temperature is equal to the shell side fluid outlet temperature, then the LMTD is (A) ∞ (B) 0 ... temperature (D) Equal to the difference between hot fluid inlet temperature and cold fluid outlet temperature

Last Answer : (B) 0

In the equation Q = UAΔt; Δt is (A) Geometric mean temperature difference (B) Arithmetic mean temperature difference (C) Logarithmic mean temperature difference (D) The difference of average bulk temperatures of hot and cold fluids

Description : In the equation Q = UAΔt; Δt is (A) Geometric mean temperature difference (B) Arithmetic mean temperature difference (C) Logarithmic mean temperature difference (D) The difference of average bulk temperatures of hot and cold fluids

Last Answer : (C) Logarithmic mean temperature difference

Hot water (0.01 m3 /min) enters the tube side of a counter current shell and tube heat exchanger at 80°C and leaves at 50°C. Cold oil (0.05 m3 /min) of density 800 kg/m3 and specific heat of 2 kJ/kg.K enters at 20°C. The log mean temperature difference in °C is approximately (A) 32 (B) 37 (C) 45 (D) 50

Description : Hot water (0.01 m3 /min) enters the tube side of a counter current shell and tube heat exchanger at 80°C and leaves at 50°C. Cold oil (0.05 m3 /min) of density 800 kg/m3 and specific heat of ... mean temperature difference in °C is approximately (A) 32 (B) 37 (C) 45 (D) 50

Last Answer : (A) 32

Maximum heat transfer rate is achieved in __________ flow. (A) Co-current (B) Counter-current (C) Turbulent (D) Laminar

Description : Maximum heat transfer rate is achieved in __________ flow. (A) Co-current (B) Counter-current (C) Turbulent (D) Laminar

Last Answer : (C) Turbulen

The water level in an open well was depressed by pumping 2.5 m and recuperated 2.87 m in 3 hours and 50 minutes. The yield of the well per minute is (A) 0.0033 (B) 0.0044 (C) 0.0055 (D) 0.0066

Description : The water level in an open well was depressed by pumping 2.5 m and recuperated 2.87 m in 3  hours and 50 minutes. The yield of the well per minute is  (A) 0.0033  (B) 0.0044  (C) 0.0055  (D) 0.0066 

Last Answer : (C) 0.0055 

A block of weight 20 kg slides with an initial velocity of 2 m sec down an inclined plane on to a spring of stiffness 10 kg/cm. If the co--efficient of friction is 0.2, angle ? = 30 the ratio of maximum compession of spring, neglecting friction to that while considering friction would be a.More than one b.One c.Less than one d.Depends on the stiffness of spring e.None of the above

Description : A block of weight 20 kg slides with an initial velocity of 2 m sec down an inclined plane on to a spring of stiffness 10 kg/cm. If the co--efficient of friction is 0.2, angle ? = 30 the ratio of ... be a.More than one b.One c.Less than one d.Depends on the stiffness of spring e.None of the above

Last Answer : a. More than one

Pick out the wrong statement. (A) 'Solvates' are chemical compounds formed by solute with their solvents. When water is the solvent, then it is called a 'hydrate' (B) In heat exchanger calculations (Δt) weighted is used in place of Δt, when it involves more than one sequence of heating or cooling i.e., desuperheating & condensation or condensation & sub-cooling (C) Heat transfer co-efficient during nucleate boiling is not influenced by the agitation imparted (D) In case of short tube vertical evaporators, area of central downtake is about 50 to 100% of the total tube cross-sectional area

Description : Pick out the wrong statement. (A) 'Solvates' are chemical compounds formed by solute with their solvents. When water is the solvent, then it is called a 'hydrate' (B) In heat exchanger ... vertical evaporators, area of central downtake is about 50 to 100% of the total tube cross-sectional area

Last Answer : (C) Heat transfer co-efficient during nucleate boiling is not influenced by the agitation imparted

Correction is applied to LMTD for __________ flow. (A) Parallel (B) Counter (C) Cross (D) None of these

Description : Correction is applied to LMTD for __________ flow. (A) Parallel (B) Counter (C) Cross (D) None of these

Last Answer : (C) Cross

A particle moves along a rough plane inclined at 30? to the horizontal. The co-efficient of friction between the particle and the plane is 0.1. Its initial velocity is 15 m/sec. The ratio of the velocity of the particle when it move down the plane to that when it move up the plane would be in the regions a.8 ? 10 b.5 ? 7 c.2 ? 3 d.4 ? 6 e.10 ? 13

Description : A particle moves along a rough plane inclined at 30? to the horizontal. The co-efficient of friction between the particle and the plane is 0.1. Its initial velocity is 15 m/sec. The ratio of the velocity of the particle when it move ... be in the regions a.8 ? 10 b.5 ? 7 c.2 ? 3 d.4 ? 6 e.10 ? 13

Last Answer : b. 5 ? 7

For aluminium, as compared to copper, all the following factors have higher values except (a) specific volume (6) electrical conductivity (c) co-efficient of linear expansion (d) resistance per unit length for same cross-section

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Last Answer : (6) electrical conductivity

Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B) The co-efficient of contraction of a Venturimeter is always unity (C) For a fixed pressure drop, the discharge of a gas through a Venturimeter is greater, when compressibility is taken into account, than when it is neglected (D) None of these

Description : Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B ... , when compressibility is taken into account, than when it is neglected (D) None of these

Last Answer : (D) None of these

A streamline is (A) The line connecting the mid-points of flow cross-sections (B) Defined for uniform flow only (C) Drawn normal to the velocity vector at every point (D) Always the path of a particle

Description : A streamline is (A) The line connecting the mid-points of flow cross-sections (B) Defined for uniform flow only (C) Drawn normal to the velocity vector at every point (D) Always the path of a particle

Last Answer : (C) Drawn normal to the velocity vector at every point

A stream line is (A) Fixed in space in steady flow (B) Always the path of particle (C) Drawn normal to the velocity vector at every point (D) A line connecting the mid points of flow cross-section

Description : A stream line is (A) Fixed in space in steady flow (B) Always the path of particle (C) Drawn normal to the velocity vector at every point (D) A line connecting the mid points of flow cross-section

Last Answer : (A) Fixed in space in steady flow

02. A flow in which each liquid particle does not have a definite path and the paths of individual particles also cross each other is called turbulent flow. A) Agree B) Disagree

Description : 02. A flow in which each liquid particle does not have a definite path and the paths of individual particles also cross each other is called turbulent flow. A) Agree B) Disagree

Last Answer : A

A flow in which each liquid particle has a definite path, and the paths of individual particles do not cross each other, is called (A) Steady flow (B) Uniform flow (C) Streamline flow (D) Turbulent flow

Description : A flow in which each liquid particle has a definite path, and the paths of individual particles do not cross each other, is called (A) Steady flow (B) Uniform flow (C) Streamline flow (D) Turbulent flow

Last Answer : Answer: Option C

The flow in which each liquid particle has a definite path and their paths do not cross each other is called (A) One dimensional flow (B) Streamline flow (C) Steady flow (D) Turbulent flow

Description : The flow in which each liquid particle has a definite path and their paths do not cross each other is called (A) One dimensional flow (B) Streamline flow (C) Steady flow (D) Turbulent flow

Last Answer : Answer: Option B

In industrial operations fluids with temperature less than __________ are set as the limit for waste heat recovery because of the risk of condensation of corrosive liquids a. 80C b. 100C c. 120C d. 200C

Description : In industrial operations fluids with temperature less than __________ are set as the limit for waste heat recovery because of the risk of condensation of corrosive liquids a. 80C b. 100C c. 120C d. 200C

Last Answer : 100C

Using an organic fluid that boils at a low temperature means that energy could be regeneratedfrom waste fluids is known as ________. a) Heat exchanger b) Heat remover c) Heat pumps d) Heat absorber`

Description : Using an organic fluid that boils at a low temperature means that energy could be regeneratedfrom waste fluids is known as ________. a) Heat exchanger b) Heat remover c) Heat pumps d) Heat absorber

Last Answer : Heat pumps

Composite property applicable to all fluids  a. Entropy  b. Enthalpy  c. Specific Heat  d. None of the above

Description : Composite property applicable to all fluids  a. Entropy  b. Enthalpy  c. Specific Heat  d. None of the above

Last Answer : Enthalpy

Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In small columns, local efficiency is larger than Murphree efficiency; in large columns local efficiency is smaller than Murphree efficiency (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s (D) The concentration and hydrodynamic boundary layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s

Pick out the wrong statement. (A) Superheated steam is preferably not used for process heating because of its low heat transfer film co-efficient (B) In a shell and tube heat exchanger, the shell pressure drop is maximum for orifice baffles (C) S.I. unit of fouling factor is Watt/m2 .°K (D) Longitudinal fins are used in extended surface heat exchangers, when the direction of fluid flow is parallel to the axis of the tube

Description : Pick out the wrong statement. (A) Superheated steam is preferably not used for process heating because of its low heat transfer film co-efficient (B) In a shell and tube heat exchanger ... surface heat exchangers, when the direction of fluid flow is parallel to the axis of the tube

Last Answer : (C) S.I. unit of fouling factor is Watt/m2 .°K

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

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

For turbulent flow in a tube, the heat transfer co-efficient is obtained from the Dittus-Boelter correlation. If the tube diameter is halved and the flow rate is doubled, then the heat transfer co-efficient will change by a factor of (A) 1 (B) 1.74 (C) 6.1 (D) 37

Description : For turbulent flow in a tube, the heat transfer co-efficient is obtained from the Dittus-Boelter correlation. If the tube diameter is halved and the flow rate is doubled, then the heat transfer co-efficient will change by a factor of (A) 1 (B) 1.74 (C) 6.1 (D) 37

Last Answer : (C) 6.1

The inside heat transfer co-efficient in case of turbulent flow of liquid in the tube side in a 1-2 shell and tube heat exchanger is increased by __________ times, when the number of tube passes is increased to 8. (A) 2 0.8 (B) 4 0.8 (C) 4 0.4 (D) 2 0.4

Description : The inside heat transfer co-efficient in case of turbulent flow of liquid in the tube side in a 1-2 shell and tube heat exchanger is increased by __________ times, when the number of tube passes is increased to 8. (A) 2 0.8 (B) 4 0.8 (C) 4 0.4 (D) 2 0.4

Last Answer : (B) 4 0.8

In an extended surface heat exchanger, fluid having lower co-efficient (A) Flows through the tube (B) Flows outside the tubes (C) Can flow either inside or outside the tubes (D) Should not be used as it gives very high pressure drop

Description : In an extended surface heat exchanger, fluid having lower co-efficient (A) Flows through the tube (B) Flows outside the tubes (C) Can flow either inside or outside the tubes (D) Should not be used as it gives very high pressure drop

Last Answer : (B) Flows outside the tubes

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 varies with the pipe diameter (D) as (A) D-1.8 (B) D-0.2 (C) D0.2 (D) D1.8

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

Heat transfer co-efficient equation for forced convection, Nu = 0.023 Re 0.8 . Pr n , is not valid, if the value of (A) n = 0.4 is used for heating (B) n = 0.3 is used for cooling (C) Reynolds number for the flow involved is > 10000 (D) Reynolds number for the flow involved is < 2100

Description : Heat transfer co-efficient equation for forced convection, Nu = 0.023 Re 0.8 . Pr n , is not valid, if the value of (A) n = 0.4 is used for heating (B) n = 0.3 is used for cooling (C) Reynolds number for the flow involved is > 10000 (D) Reynolds number for the flow involved is < 2100

Last Answer : (D) Reynolds number for the flow involved is < 2100

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 deviationin practice ?(A) Constant overall heat transfer co-efficient.(B) Constant rate of fluid flow(C) Constant specific heat(D) No partial phase change in the system

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

For a laminar flow of fluid in a circular tube, 'h1 ' is the convective heat transfer co-efficient at velocity 'V1 '. If the velocity is reduced by half and assuming the fluid properties are constant, the new convective heat transfer co-efficient is (A) 1.26 h1(B) 0.794 h1(C) 0.574 h1(D) 1.741 h1

Description : For a laminar flow of fluid in a circular tube, 'h1 ' is the convective heat transfer co-efficient at velocity 'V1 '. If the velocity is reduced by half and assuming the fluid properties are constant, the new convective heat transfer co-efficient is (A) 1.26 h1 (B) 0.794 h1 (C) 0.574 h1 (D) 1.741 h1

Last Answer : (B) 0.794 h1

Cd , Cc and Cv are related (for flow through an orifice) as (where, Cd = discharge co-efficient, Cc = co-efficient of contraction = (area of jet at vena￾contracta/area of opening), Cv = co-efficient of velocity = (actual velocity at vena-contracta/theoretical velocity). (A) Cd = Cc /Cv (B) Cd = Cc .Cv (C) Cd = Cv / Cc (D) None of these

Description : Cd , Cc and Cv are related (for flow through an orifice) as (where, Cd = discharge co-efficient, Cc = co-efficient of contraction = (area of jet at vena￾contracta/area of opening), Cv = co-efficient of velocity = (actual velocity ... A) Cd = Cc /Cv (B) Cd = Cc .Cv (C) Cd = Cv / Cc (D) None of these

Last Answer : (B) Cd = Cc .Cv

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 to have the same hydraulic roughness, when they have equal values of (A) Relative roughness (B) Absolute roughness (C) Friction co-efficient for flows at equal Reynold number (D) All (A), (B) & (C)

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

Drag co-efficient for flow past immersed body is the ratio of __________ to the product of velocity head and density. (A) Shear stress (B) Shear force (C) Average drag per unit projected area (D) None of these

Description : Drag co-efficient for flow past immersed body is the ratio of __________ to the product of velocity head and density. (A) Shear stress (B) Shear force (C) Average drag per unit projected area (D) None of these

Last Answer : (C) Average drag per unit projected area

Which of the following is not a dimension-less group used in catalysis? (Where, D = dispersion co-efficient, cm2 /sec.D1 = diffusion co-efficient; cm2 /sec L = length of the reactor, cm t = time, sec, v = volumetric flow rate, cm3 /sec. V = volume, cm3 .) (A) Reactor dispersion number (D/vL) (B) Reduced time (vt/V) (C) Thiele modulus L √(k/D1 ) (D) None of these

Description : Which of the following is not a dimension-less group used in catalysis? (Where, D = dispersion co-efficient, cm2 /sec.D1 = diffusion co-efficient; cm2 /sec L = length of the reactor, cm t = time, sec, v = volumetric ... (D/vL) (B) Reduced time (vt/V) (C) Thiele modulus L √(k/D1 ) (D) None of these

Last Answer : (D) None of these