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

Correction is applied to LMTD for __________ flow.

(A) Parallel

(B) Counter

(C) Cross

(D) None of these

by

1 Answer

Answer :

(C) Cross


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

LMTD correction factor which is to be applied for a cross-flow heat exchanger increases with increase in the number of shell passes. Its value for a single pass cross flow heat exchanger is (A) 0 (B) 1 (C) > 1 (D) < 1

Description : LMTD correction factor which is to be applied for a cross-flow heat exchanger increases with increase in the number of shell passes. Its value for a single pass cross flow heat exchanger is (A) 0 (B) 1 (C) > 1 (D) < 1

Last Answer : (D) < 1

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'

Description : 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 ... Parallel (B) Mixed (C) Counter flow (D) Same in either 'a', b' or 'c'

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

In counter flow compared to parallel flow, (A) LMTD is greater (B) Less surface area is required for a given heat transfer rate (C) Both (A) and (B) (D) More surface area is required for a given heat transfer rate

Description : In counter flow compared to parallel flow, (A) LMTD is greater (B) Less surface area is required for a given heat transfer rate (C) Both (A) and (B) (D) More surface area is required for a given heat transfer rate

Last Answer : (C) Both (A) and (B)

In a liquid-liquid heat exchanger, for the same process temperature, the ratio of the LMTD in parallel flow to the LMTD in counter flow is always (A) < 1 (B) > 1 (C) 1 (D) ∞

Description : In a liquid-liquid heat exchanger, for the same process temperature, the ratio of the LMTD in parallel flow to the LMTD in counter flow is always (A) < 1 (B) > 1 (C) 1 (D) ∞

Last Answer : (A) < 1

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)

case of condensers & evaporators operating under given terminal conditions, LMTD (logarithmic mean temperature difference) for counter flow as compared to that for parallel flow is (A) More (B) Less (C) Equal (D) Much more

Description : case of condensers & evaporators operating under given terminal conditions, LMTD (logarithmic mean temperature difference) for counter flow as compared to that for parallel flow is (A) More (B) Less (C) Equal (D) Much more

Last Answer : Option C

It is not recommended to use a 1-2 shell and tube heat exchanger for a particular heat duty, whenever the LMTD correction factor is (A) > 0.75 (B) < 0.75 (C) < 0.50 (D) < 0.25

Description : It is not recommended to use a 1-2 shell and tube heat exchanger for a particular heat duty, whenever the LMTD correction factor is (A) > 0.75 (B) < 0.75 (C) < 0.50 (D) < 0.25

Last Answer : (B) < 0.75

LMTD can't be used as such without a correction factor for the (A) Multipass heat exchanger (B) Baffled heat exchanger (C) Condensation of mixed vapour in a condenser (D) All (A) (B) and (C)

Description : LMTD can't be used as such without a correction factor for the (A) Multipass heat exchanger (B) Baffled heat exchanger (C) Condensation of mixed vapour in a condenser (D) All (A) (B) and (C)

Last Answer : (D) All (A) (B) and (C)

For a multipass shell and tube heat exchanger, the LMTD correction factor is always (A) 1 (B) > 1 (C) < 1 (D) Between 1 & 2

Description : For a multipass shell and tube heat exchanger, the LMTD correction factor is always (A) 1 (B) > 1 (C) < 1 (D) Between 1 & 2

Last Answer : (C) < 1

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

A standard steel tape of length 30 m and cross-section 15 × 1.0 mm was standardised at 25°C and at 30 kg pull. While measuring a base line at the same temperature, the pull applied was 40 kg. If the modulus of elasticity of steel tape is 2.2 × 106 kg/cm2 , the correction to be applied is (A) - 0.000909 m (B) + 0.0909 m (C) 0.000909 m (D) None of these

Description : A standard steel tape of length 30 m and cross-section 15 1.0 mm was standardised at 25°C and at 30 kg pull. While measuring a base line at the same temperature, the pull applied was 40 kg. If the modulus of elasticity of ... (A) - 0.000909 m (B) + 0.0909 m (C) 0.000909 m (D) None of these

Last Answer : (A) - 0.000909 m

The assumption on which the trapezoidal formula for volumes is based, is (A) The end sections are parallel planes (B) The mid-area of a pyramid is half the average area of the ends (C) The volume of the Prismoidal is over-estimated and hence a Prismoidal correction is applied (D) All the above

Description : The assumption on which the trapezoidal formula for volumes is based, is (A) The end sections are parallel planes (B) The mid-area of a pyramid is half the average area of the ends (C) The volume of the Prismoidal is over-estimated and hence a Prismoidal correction is applied (D) All the above

Last Answer : (D) All the above

Correction for capillary effect in manometers (used for pressure measurement) need not be applied, if diameter of the manometer tube is __________ mm. (A) < 4 (B) > 4 (C) > 12.5 (D) < 10

Description : Correction for capillary effect in manometers (used for pressure measurement) need not be applied, if diameter of the manometer tube is __________ mm. (A) < 4 (B) > 4 (C) > 12.5 (D) < 10

Last Answer : (C) > 12.5

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

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

A process stream of dilute aqueous solution flowing at the rate of10 Kg.s -1 is to be heated. Steam condensate at 95°C is available for heating purpose, also at a rate of 10 Kg.s -1 . A 1 - 1 shell and tube heat exchanger is available. The best arrangement is (A) Counter flow with process stream on shell side (B) Counter flow with process stream on tube side (C) Parallel flow with process stream on shell side (D) Parallel flow with process stream on tube side

Description : A process stream of dilute aqueous solution flowing at the rate of10 Kg.s -1 is to be heated. Steam condensate at 95°C is available for heating purpose, also at a rate of 10 Kg.s -1 . A 1 ... side (C) Parallel flow with process stream on shell side (D) Parallel flow with process stream on tube side

Last Answer : (A) Counter flow with process stream on shell side

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

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

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

Description : 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

Last Answer : Counter current mode

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

If is the pull applied at the ends of tape in kg, is the length of tape between end marks in metres, is the weight of the tape in kg per metre run, then sag correction (A) C = w²l3 /24F² (B) C = w 3 l²/24F² (C) C = w²l3 /24F3 (D) C = 24w²l3 /80F

Description : If is the pull applied at the ends of tape in kg, is the length of tape between end marks in metres, is the weight of the tape in kg per metre run, then sag correction (A) C = w²l3 /24F² (B) C = w 3 l²/24F² (C) C = w²l3 /24F3 (D) C = 24w²l3 /80F

Last Answer : (A) C = w²l3 /24F²

.When correction preparation for re contouring of occlusal surface is to be applied, grinding only of the adjusted surface: A. Should not be felt flat B. Requires a flat crown C. Requires no contact with adjacent teeth D. Should be felt flat

Description : .When correction preparation for re contouring of occlusal surface is to be applied, grinding only of the adjusted surface: A. Should not be felt flat B. Requires a flat crown C. Requires no contact with adjacent teeth D. Should be felt flat

Last Answer : A. Should not be felt flat

The correction to be applied in decimal adder to the generated sum is (A) 00101 (B) 00110 (C) 01101 (D) 01010

Description : The correction to be applied in decimal adder to the generated sum is (A) 00101 (B) 00110 (C) 01101 (D) 01010

Last Answer : Ans: B The correction to be applied in decimal adder to the generated sum is 00110. When the four bit sum is more than 9 then the sum is invalid. In such cases, add +6(i.e. 0110) to the ... the six invalid states. If a carry is generated when adding 6, add the carry to the next four bit group .

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

The outlet temperature of cooling water in a heat exchanger is generally not allowed to exceed above 50°C in industrial practice mainly to avoid (A) Its evaporation loss (B) Excessive corrosion (C) Uneconomic LMTD (D) Decrease in heat exchanger efficiency

Description : The outlet temperature of cooling water in a heat exchanger is generally not allowed to exceed above 50°C in industrial practice mainly to avoid (A) Its evaporation loss (B) Excessive corrosion (C) Uneconomic LMTD (D) Decrease in heat exchanger efficiency

Last Answer : (B) Excessive corrosion

Log mean temperature difference (LMTD) cannot be used, if (A) Heat transfer co-efficient over the entire heat exchanger is not constant (B) There exists an unsteady state (C) The heat capacity is not constant and there is a phase change (D) None of these

Description : Log mean temperature difference (LMTD) cannot be used, if (A) Heat transfer co-efficient over the entire heat exchanger is not constant (B) There exists an unsteady state (C) The heat capacity is not constant and there is a phase change (D) None of these

Last Answer : (D) None of these

In a heat exchanger, the rate of heat transfer from the hot fluid to the cold fluid (A) Varies directly as the area and the LMTD (B) Directly proportional to LMTD and inversely proportional to the area (C) Varies as square of the area (D) None of these

Description : In a heat exchanger, the rate of heat transfer from the hot fluid to the cold fluid (A) Varies directly as the area and the LMTD (B) Directly proportional to LMTD and inversely proportional to the area (C) Varies as square of the area (D) None of these

Last Answer : (A) Varies directly as the area and the LMTD

For a heat exchanger, will the overall heat transfer coefficient increase along with an increase in LMTD (log mean temperature difference) around the unit?

Description : For a heat exchanger, will the overall heat transfer coefficient increase along with an increase in LMTD (log mean temperature difference) around the unit?

Last Answer : The overall heat transfer coefficient is generally weakly dependent on temperature. As the temperatures of the fluids change, the degree to which the overall heat transfer coefficient will be affected depends ... with temperature as I've noted and the U-value will decrease over time with fouling).

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

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) ∞

The kinetic energy correction factor for velocity distribution of laminar flow is (A) 0.5 (B) 1.66 (C) 1 (D) 2

Description : The kinetic energy correction factor for velocity distribution of laminar flow is (A) 0.5 (B) 1.66 (C) 1 (D) 2

Last Answer : (B) 1.66

Momentum correction factor used in fluid flow problems accounts for the (A) Change in direction of flow (B) Change in total energy (C) Change in pressure (D) Non uniform direction of velocities at inlet & outlet sections

Description : Momentum correction factor used in fluid flow problems accounts for the (A) Change in direction of flow (B) Change in total energy (C) Change in pressure (D) Non uniform direction of velocities at inlet & outlet sections

Last Answer : (D) Non uniform direction of velocities at inlet & outlet sections

The momentum correction factor for the velocity distribution of laminar flow is (A) 1.3 (B) 1.66 (C) 2.5 (D) None of these

Description : The momentum correction factor for the velocity distribution of laminar flow is (A) 1.3 (B) 1.66 (C) 2.5 (D) None of these

Last Answer : (D) None of these

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

Velocity distribution for flow between two fixed parallel plates (A) Varies parabolically across the section (B) Is constant over the entire cross-section (C) Is zero at the plates and increases linearly to the mid-plane (D) None of these

Description : Velocity distribution for flow between two fixed parallel plates (A) Varies parabolically across the section (B) Is constant over the entire cross-section (C) Is zero at the plates and increases linearly to the mid-plane (D) None of these

Last Answer : (A) Varies parabolically across the section

If h1 and h2 are the differences in level between ground and the formation levels, m is the slope of the sloping sides. D is the distance between the cross sections then, Prismoidal correction for a level section is (A) D/2m(h1 - h2) (B) D/3m(h1 - h2) (C) D/6m(h1 - h2)2(D) D/6m(h1 - h2)3

Description : If h1 and h2 are the differences in level between ground and the formation levels, m is the slope of the sloping sides. D is the distance between the cross sections then, Prismoidal correction for a level section is (A) D/2m(h1 - h2) (B) D/3m(h1 - h2) (C) D/6m(h1 - h2)2 (D) D/6m(h1 - h2)3

Last Answer : (C) D/6m(h1 - h2)2

Pick up the incorrect statement from the following: (A) While measuring a distance with a tape of length 100.005 m, the distance to be increasing by 0.005 m for each tape length (B) An increase in temperature causes a tape to increase in length and the measured distance is too large (C) The straight distance between end points of a suspended tape is reduced by an amount called the sag correction (D) A 100 m tape of cross section 10 mm × 0.25 mm stretches about 10 mm under 5 kg pull

Description : Pick up the incorrect statement from the following: (A) While measuring a distance with a tape of length 100.005 m, the distance to be increasing by 0.005 m for each tape length (B) An increase in ... ) A 100 m tape of cross section 10 mm 0.25 mm stretches about 10 mm under 5 kg pull

Last Answer : (B) An increase in temperature causes a tape to increase in length and the measured distance is too large

For stripping of a gas in a counter current stripper, the operating line (A) Lies above the equilibrium curve (B) Lies below the equilibrium curve (C) Can lie above or below the equilibrium curve (D) Is always parallel to the equilibrium curve

Description : For stripping of a gas in a counter current stripper, the operating line (A) Lies above the equilibrium curve (B) Lies below the equilibrium curve (C) Can lie above or below the equilibrium curve (D) Is always parallel to the equilibrium curve

Last Answer : (C) Can lie above or below the equilibrium curve

Article addressed to deceased person a) Delivery such articles to any near relative of the deceased who may have applied for them in case uninsured article. b) Delivery such articles to any near relative of the deceased who may have applied for them in case do not appear to contain any valuable property c) Delivery such articles to any near relative of the deceased who may have applied for them in case no counter –claimant or likelihood of dispute. d) All the above

Description : Article addressed to deceased person a) Delivery such articles to any near relative of the deceased who may have applied for them in case uninsured article. b) Delivery such articles to any near relative ... applied for them in case no counter -claimant or likelihood of dispute. d) All the above

Last Answer : d) All the above

. What type of counter has clock pulses applied to all FFs?

Description : . What type of counter has clock pulses applied to all FFs?

Last Answer : Synchronous.

An approximately __________ process exemplifies the flow of a gas through a very long pipe of uniform cross-section. (A) Adiabatic (B) Isothermal (C) Isentropic (D) Isochoric

Description : An approximately __________ process exemplifies the flow of a gas through a very long pipe of uniform cross-section. (A) Adiabatic (B) Isothermal (C) Isentropic (D) Isochoric

Last Answer : (B) Isothermal

In case of parallel flow heat exchanger, the lowest temperature theoretically attainable by the hot fluid is __________ the outlet temperature of the cold fluid. (A) Equal to (B) More than (C) Less than (D) Either more or less than (depending upon the fluid)

Description : In case of parallel flow heat exchanger, the lowest temperature theoretically attainable by the hot fluid is __________ the outlet temperature of the cold fluid. (A) Equal to (B) More than (C) Less than (D) Either more or less than (depending upon the fluid)

Last Answer : (A) Equal to

In a counter-current liquid extractor (A) Both liquids flow at fixed rate (B) Both liquids can have any desired flow rate (C) Only one of the liquids may be pumped at any desired rate (D) Liquid’s flow rate depends upon the temperature and pressure

Description : In a counter-current liquid extractor (A) Both liquids flow at fixed rate (B) Both liquids can have any desired flow rate (C) Only one of the liquids may be pumped at any desired rate (D) Liquid’s flow rate depends upon the temperature and pressure

Last Answer : (C) Only one of the liquids may be pumped at any desired rate

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 as the ratio of the concentration gradient at wall to the overall concentration difference (C) According to film theory for equimolar counter diffusion, the mass transfer coefficient is given by DAB(B)P - 3, Q - 2 (D) The z-component of the total mass flux of a component A in binary mixture of A and B is given by - Dab'.dCA/dz

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

With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop (A) Decreases (B) Remains unchanged (C) Increases (D) Decreases exponentially

Description : With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop (A) Decreases (B) Remains unchanged (C) Increases (D) Decreases exponentially

Last Answer : (C) Increases

In a semi-batch reactor (A) Velocity of reaction can be controlled (B) Maximum conversion can be controlled (C) Both the reactants flow counter-currently (D) Residence time is constant

Description : In a semi-batch reactor (A) Velocity of reaction can be controlled (B) Maximum conversion can be controlled (C) Both the reactants flow counter-currently (D) Residence time is constant

Last Answer : (A) Velocity of reaction can be controlled

Wet chlorine gas produced during electrolysis of brine is dehydrated by (A) Spraying 66° Be H2SO4 counter current to the flow of the gas (B) Passing it through a bed of diatomaceous earth (C) Passing it through a bed of silica gel (D) None of these

Description : Wet chlorine gas produced during electrolysis of brine is dehydrated by (A) Spraying 66° Be H2SO4 counter current to the flow of the gas (B) Passing it through a bed of diatomaceous earth (C) Passing it through a bed of silica gel (D) None of these

Last Answer : (A) Spraying 66° Be H2SO4 counter current to the flow of the gas