The actual temperature drop across the heating surface in an evaporator depends on the (A) Feed (B) Depth of liquid over heating surface (C) Pressure difference between steam chest and vapour space (D) All (A), (B) and (C)

The actual temperature drop across the heating surface in an

evaporator depends on the

(A) Feed

(B) Depth of liquid over heating surface

(C) Pressure difference between steam chest and vapour space

(D) All (A), (B) and (C)

by

1 Answer

Answer :

(D) All (A), (B) and (C)

by

Related questions

The actual temperature drop across the heating surface of an evaporator depends on the (A) Liquid depth over the heating surface (B) Solution being evaporated (C) Pressure difference between the steam chest and the vapor space above the boiling liquid (D) All (A), (B) and (C)

Description : The actual temperature drop across the heating surface of an evaporator depends on the (A) Liquid depth over the heating surface (B) Solution being evaporated (C) Pressure difference between the steam chest and the vapor space above the boiling liquid (D) All (A), (B) and (C)

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

Vacuum is generally maintained in the vapour space of an evaporator mainly to (A) Get economical temperature difference by using moderate pressure steam (B) Facilitate forward feeding in multiple effect evaporation (C) Concentrate heat sensitive materials (D) Achieve very high concentration of the final product

Description : Vacuum is generally maintained in the vapour space of an evaporator mainly to (A) Get economical temperature difference by using moderate pressure steam (B) Facilitate forward ... (C) Concentrate heat sensitive materials (D) Achieve very high concentration of the final product

Last Answer : (A) Get economical temperature difference by using moderate pressure steam

In sub-cooled boiling, (A) Temperature of the heating surface is less than the boiling point of the liquid (B) Temperature of the heating surface is more than the boiling point of the liquid (C) Bubbles from heating surface are absorbed by the mass of the liquid (D) Very large vapour space is necessary

Description : In sub-cooled boiling, (A) Temperature of the heating surface is less than the boiling point of the liquid (B) Temperature of the heating surface is more than the boiling point of the liquid (C) ... from heating surface are absorbed by the mass of the liquid (D) Very large vapour space is necessary

Last Answer : (B) Temperature of the heating surface is more than the boiling point of the liquid

Economy of an evaporator is influenced by the (A) Steam pressure (B) Feed temperature (C) Number of effect (D) Both (B) & (C)

Description : Economy of an evaporator is influenced by the (A) Steam pressure (B) Feed temperature (C) Number of effect (D) Both (B) & (C)

Last Answer : (D) Both (B) & (C)

. A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because (A) Total heat transfer area of all the effects is -less than that in a single effect evaporator system (B) Total amount of vapor produced per Kg of feed steam in a multiple effect system is much higher than in a single effect (C) Boiling point elevation in a single effect system is much higher than that in any effect in a multi-effect system (D) Heat transfer co-efficient in a single effect is much lower than that in any effect in a multi-effect system

Description : . A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because (A) Total heat transfer area of ... in a single effect is much lower than that in any effect in a multi-effect system

Last Answer : (B) Total amount of vapor produced per Kg of feed steam in a multiple effect system is much higher than in a single effect

Pick out the wrong statement. (A) Economy of a multiple effect evaporator is not influenced by the boiling point elevation (B) Two identical cubes of iron and copper will have the same heat content under the same conditions of temperature (C) Double pipe heat exchangers are mostly used in the field of refrigeration (D) Finned tube heat exchangers are suitable for heating air by steam

Description : Pick out the wrong statement. (A) Economy of a multiple effect evaporator is not influenced by the boiling point elevation (B) Two identical cubes of iron and copper will have the same heat ... in the field of refrigeration (D) Finned tube heat exchangers are suitable for heating air by steam

Last Answer : (B) Two identical cubes of iron and copper will have the same heat content under the same conditions of temperature

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

Relative humidity is the ratio of the (A) Partial pressure of the vapour to the vapour pressure of the liquid at room temperature (B) Partial pressure of the vapour to the vapour pressure of the liquid at gas temperature (C) Actual humidity to saturation humidity (D) None of these

Description : Relative humidity is the ratio of the (A) Partial pressure of the vapour to the vapour pressure of the liquid at room temperature (B) Partial pressure of the vapour to the vapour pressure of the liquid at gas temperature (C) Actual humidity to saturation humidity (D) None of these

Last Answer : (B) Partial pressure of the vapour to the vapour pressure of the liquid at gas temperatur

Pick out the wrong statement: (A) The capacity of an evaporator is reduced by the boiling point elevation (B) Corrosive liquid is normally passed through the tubes in a shell and tube heat exchanger (C) Steam jet ejector is used for vapor compression in a thermal recompression evaporator (D) Heat sensitive materials should be concentrated in high pressure evaporators

Description : Pick out the wrong statement: (A) The capacity of an evaporator is reduced by the boiling point elevation (B) Corrosive liquid is normally passed through the tubes in a ... recompression evaporator (D) Heat sensitive materials should be concentrated in high pressure evaporators

Last Answer : (D) Heat sensitive materials should be concentrated in high pressure evaporators

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

In case of steam distillation, the steam leaving the liquid is not completely saturated with distillate vapour, because(A) Temperature is less(B) Total pressure is less(C) Mixing of steam with the material being vaporised is not so intimate asto result in equilibrium condition(D) Saturated steam is used for steam distillation

Description : In case of steam distillation, the steam leaving the liquid is not completely saturated with distillate vapour, because (A) Temperature is less (B) Total pressure is less (C) Mixing of steam ... not so intimate as to result in equilibrium condition (D) Saturated steam is used for steam distillation

Last Answer : (C) Mixing of steam with the material being vaporised is not so intimate as to result in equilibrium condition

In a single evaporator system, the steam economy __________ by creating vacuum in the evaporator. (A) Increases (B) Decreases (C) Remain constant (D) May increase or decrease, depends on the vacuum

Description : In a single evaporator system, the steam economy __________ by creating vacuum in the evaporator. (A) Increases (B) Decreases (C) Remain constant (D) May increase or decrease, depends on the vacuum

Last Answer : (A) Increases

In case of vertical tube evaporator, with increase in liquor level, the overall heat transfer co-efficient (A) Increases (B) Decreases (C) Is not affected (D) May increase or decrease; depends on the feed

Description : In case of vertical tube evaporator, with increase in liquor level, the overall heat transfer co-efficient (A) Increases (B) Decreases (C) Is not affected (D) May increase or decrease; depends on the feed

Last Answer : (B) Decreases

Through what is feed water from hot-well is passed through, before entering steam and water drum in Lamont boiler? a. Evaporator tubes b. Economizer c. Distributor header d. Circulating pump

Description : Through what is feed water from hot-well is passed through, before entering steam and water drum in Lamont boiler? a. Evaporator tubes b. Economizer c. Distributor header d. Circulating pump

Last Answer : b. Economizer

For concentrating an aqueous solution of a material like anhydrous Na2SO4, whose solubility decreases with rise in temperature, the most suitable evaporator is a __________ evaporator. (A) High pressure (B) Vacuum (C) Backward feed (D) None of these

Description : For concentrating an aqueous solution of a material like anhydrous Na2SO4, whose solubility decreases with rise in temperature, the most suitable evaporator is a __________ evaporator. (A) High pressure (B) Vacuum (C) Backward feed (D) None of these

Last Answer : (B) Vacuum

In vapour compression refrigeration system, refrigerant occurs as liquid between (a) condenser and expansion valve (b) compressor and evaporator (c) expansion valve and evaporator (d) compressor and condenser

Description : In vapour compression refrigeration system, refrigerant occurs as liquid between (a) condenser and expansion valve (b) compressor and evaporator (c) expansion valve and evaporator (d) compressor and condenser

Last Answer : Ans: c

In a flooded evaporator refrigerator, an accumulator at suction of compressor is used to (a) collect liquid refrigerant and prevent it from going to compressor (b) detect liquid in vapour (c) superheat the vapour (d) increase refrigeration effect

Description : In a flooded evaporator refrigerator, an accumulator at suction of compressor is used to (a) collect liquid refrigerant and prevent it from going to compressor (b) detect liquid in vapour (c) superheat the vapour (d) increase refrigeration effect

Last Answer : Ans: a

Back-trapping in a distillation column (A) Increases tray efficiency (B) Decreases tray efficiency (C) Reduces pressure drop (D) Is desirable, as it provides improved vapour-liquid contact

Description : Back-trapping in a distillation column (A) Increases tray efficiency (B) Decreases tray efficiency (C) Reduces pressure drop (D) Is desirable, as it provides improved vapour-liquid contact

Last Answer : (B) Decreases tray efficiency

Kg of liquid evaporated per hour in an evaporator is defined as its (A) Capacity (B) Economy (C) Steam load (D) None of these

Description : Kg of liquid evaporated per hour in an evaporator is defined as its (A) Capacity (B) Economy (C) Steam load (D) None of these

Last Answer : (A) Capacity

Pick out the wrong statement. (A) Bubble size increases with the dynamic viscosity of the liquid in case of nucleate pool boiling (B) Thermal conductivity of a dry material is more than that of the damp material (C) Ratio of its capacity to economy equals the steam consumption in kg/hr in an evaporator (D) Vaporisation of organic substances in evaporator mostly causes foam formation

Description : Pick out the wrong statement. (A) Bubble size increases with the dynamic viscosity of the liquid in case of nucleate pool boiling (B) Thermal conductivity of a dry material is more than ... in kg/hr in an evaporator (D) Vaporisation of organic substances in evaporator mostly causes foam formation

Last Answer : (B) Thermal conductivity of a dry material is more than that of the damp material

In a forward feed multiple effect evaporator unit (A) Viscosity of liquid is highest in first effect (B) Transfer from effect to effect is done by pumps (C) No pump is required to withdraw the product from the last effect (D) None of these

Description : In a forward feed multiple effect evaporator unit (A) Viscosity of liquid is highest in first effect (B) Transfer from effect to effect is done by pumps (C) No pump is required to withdraw the product from the last effect (D) None of these

Last Answer : (D) None of these

Which of the following psychrometric processes is followed by water vapour laden unsaturated air, when it is passed through solid or liquid adsorbent? (A) Cooling and dehumidification (B) Heating and dehumidification at almost constant wet bulb temperature (C) Dehumidification with dry bulb temperature remaining constant (D) None of these

Description : Which of the following psychrometric processes is followed by water vapour laden unsaturated air, when it is passed through solid or liquid adsorbent? (A) Cooling and dehumidification ... (C) Dehumidification with dry bulb temperature remaining constant (D) None of these

Last Answer : (B) Heating and dehumidification at almost constant wet bulb temperature

Lowering of condenser temperature (keeping the evaporator temperature constant) in case of vapour compression refrigeration system results in (A) Increased COP (B) Same COP (C) Decreased COP (D) Increased or decreased COP; depending upon the type of refrigerant

Description : Lowering of condenser temperature (keeping the evaporator temperature constant) in case of vapour compression refrigeration system results in (A) Increased COP (B) Same COP (C) Decreased COP (D) Increased or decreased COP; depending upon the type of refrigerant

Last Answer : (A) Increased COP

The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is (A) Less pronounced (B) More pronounced (C) Equal (D) Data insufficient, can't be predicted

Description : The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is (A) Less pronounced (B) More pronounced (C) Equal (D) Data insufficient, can't be predicted

Last Answer : (B) More pronounced

In vapour compression refrigeration system, if the evaporator temperature and the condenser temperatures are -13°C and 37°C respectively, the Carnot COP will be (A) 5.2 (B) 6.2 (C) 0.168 (D) Data insufficient, can't be found out

Description : In vapour compression refrigeration system, if the evaporator temperature and the condenser temperatures are -13°C and 37°C respectively, the Carnot COP will be (A) 5.2 (B) 6.2 (C) 0.168 (D) Data insufficient, can't be found out

Last Answer : A) 5.2

Stage efficiency in a leaching process depends on the (A) Time of contact between the solid and the solution (B) Rate of diffusion of the solute through the solid and into the liquid (C) Both (A) and (B) (D) Vapour pressure of the solution

Description : Stage efficiency in a leaching process depends on the (A) Time of contact between the solid and the solution (B) Rate of diffusion of the solute through the solid and into the liquid (C) Both (A) and (B) (D) Vapour pressure of the solution

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

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

Explain the type of multiple effect evaporator feed arrangement used for handling viscous liquid.

Description : Explain the type of multiple effect evaporator feed arrangement used for handling viscous liquid.

Last Answer : Backward feed arrangement  If the liquid is very viscous, then we have to adopt backward feed arrangement. In this arrangement, the feed solution and vapour flow is in opposite direction. Fresh feed is ... Not very common as it need pump. At low values of feed temperature higher economy.

Where does the lowest temperature occur in a vapour compression cycle ? (a) condenser (b) evaporator (c) compressor (d) expansion valve

Description : Where does the lowest temperature occur in a vapour compression cycle ? (a) condenser (b) evaporator (c) compressor (d) expansion valve

Last Answer : Ans: b

The higher temperature in vapour compression cycle occurs at (a) compressor discharge. (b) expansion valve (c) evaporator (d) condenser discharge

Description : The higher temperature in vapour compression cycle occurs at (a) compressor discharge. (b) expansion valve (c) evaporator (d) condenser discharge

Last Answer : Ans: a

In case of a vertical tube evaporator, with increase in the liquor level, the (A) Capacity of the evaporator is decreased (B) Capacity of the evaporator is increased (C) True temperature drop increases (D) Both (B) and (C)

Description : In case of a vertical tube evaporator, with increase in the liquor level, the (A) Capacity of the evaporator is decreased (B) Capacity of the evaporator is increased (C) True temperature drop increases (D) Both (B) and (C)

Last Answer : (A) Capacity of the evaporator is decreased

Increasing the liquor level in the evaporator results in the (A) Decreased capacity (B) Increase in liquor film co-efficient (C) Decreased effect of hydrostatic head (D) Increased true temperature drop

Description : Increasing the liquor level in the evaporator results in the (A) Decreased capacity (B) Increase in liquor film co-efficient (C) Decreased effect of hydrostatic head (D) Increased true temperature drop

Last Answer : (A) Decreased capacity

. In a backward feed multiple effect evaporator (A) Feed is introduced in the first effect (B) Feed flows from low pressure to high pressure (C) No pumps are required between successive effects (D) None of these

Description : . In a backward feed multiple effect evaporator (A) Feed is introduced in the first effect (B) Feed flows from low pressure to high pressure (C) No pumps are required between successive effects (D) None of these

Last Answer : (B) Feed flows from low pressure to high pressure

In a forward feed multiple effect evaporator, the pressure is (A) Highest in last effect (B) Lowest in last effect (C) Same in all effects (D) Dependent on the number of effects

Description : In a forward feed multiple effect evaporator, the pressure is (A) Highest in last effect (B) Lowest in last effect (C) Same in all effects (D) Dependent on the number of effects

Last Answer : (B) Lowest in last effect

Economy of a multiple effect evaporator is not influenced much by the (A) Boiling point elevations (B) Temperature of the feed (C) Rate of heat transfer (D) Ratio of the weight of the thin liquor to thick liquor

Description : Economy of a multiple effect evaporator is not influenced much by the (A) Boiling point elevations (B) Temperature of the feed (C) Rate of heat transfer (D) Ratio of the weight of the thin liquor to thick liquor

Last Answer : (A) Boiling point elevations

On average, how do low clouds affect the surface temperature (compared to a clear sky)? (a) Low clouds warm the surface by increasing the greenhouse effect (b) Low clouds cool the surface by increasing the energy emitted to space (c) Low clouds cool the surface by increasing the albedo (d) It depends on whether they are comprised of ice or liquid water

Description : On average, how do low clouds affect the surface temperature (compared to a clear sky)? (a) Low clouds warm the surface by increasing the greenhouse effect (b) Low clouds cool the surface by ... surface by increasing the albedo (d) It depends on whether they are comprised of ice or liquid water

Last Answer : (c) Low clouds cool the surface by increasing the albedo

On average, how do high clouds affect the surface temperature (compared to a clear sky)? (a) High clouds warm the surface by increasing the greenhouse effect (b) High clouds cool the surface by increasing the energy emitted to space (c) High clouds cool the surface by increasing the albedo (d) It depends on whether they are comprised of ice or liquid water

Description : On average, how do high clouds affect the surface temperature (compared to a clear sky)? (a) High clouds warm the surface by increasing the greenhouse effect (b) High clouds cool the surface ... surface by increasing the albedo (d) It depends on whether they are comprised of ice or liquid water

Last Answer : High clouds warm the surface by increasing the greenhouse effect

Clausius-Clapeyron Equation gives accurate result, when the (A) Vapour pressure is relatively low and the temperature does not vary over wide limits (B) Vapour obeys the ideal gas law and the latent heat of vaporisation is constant (C) Volume in the liquid state is negligible compared with that in the vapour state (D) All (A), (B) and (C)

Description : Clausius-Clapeyron Equation gives accurate result, when the (A) Vapour pressure is relatively low and the temperature does not vary over wide limits (B) Vapour obeys the ideal gas law and the latent heat of ... is negligible compared with that in the vapour state (D) All (A), (B) and (C)

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

The capacity of double-effect evaporator is less than half of the capacity of two single effects, each of which is operating over same terminal temperature difference, when the (A) Solution has an elevation of boiling point (B) Evaporators operate under vacuum (C) Evaporators operate at atmospheric pressure (D) None of these

Description : The capacity of double-effect evaporator is less than half of the capacity of two single effects, each of which is operating over same terminal temperature difference, when the (A) Solution has ... B) Evaporators operate under vacuum (C) Evaporators operate at atmospheric pressure (D) None of these

Last Answer : (A) Solution has an elevation of boiling point

The vapour pressure exerted by the moisture contained in a wet solid depends upon the (A) Nature of the moisture (B) Temperature (C) Nature of the solid (D) All (A), (B) and (C)

Description : The vapour pressure exerted by the moisture contained in a wet solid depends upon the (A) Nature of the moisture (B) Temperature (C) Nature of the solid (D) All (A), (B) and (C)

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

Steam undergoes isentropic expansion in a turbine from 5000 kPa and 400°C (entropy = 6.65 kJ/kg K) to 150 kPa) (entropy of saturated liquid = 1.4336 kJ/kg. K, entropy of saturated vapour = 7.2234 kJ/kg. K) The exit condition of steam is (A) Superheated vapour (B) Partially condensed vapour with quality of 0.9 (C) Saturated vapour (D) Partially condensed vapour with quality of 0.1

Description : Steam undergoes isentropic expansion in a turbine from 5000 kPa and 400°C (entropy = 6.65 kJ/kg K) to 150 kPa) (entropy of saturated liquid = 1.4336 kJ/kg. K, entropy of saturated vapour = 7.2234 ... vapour with quality of 0.9 (C) Saturated vapour (D) Partially condensed vapour with quality of 0.1

Last Answer : (A) Superheated vapour

The feed to fractionating column is changed from saturated vapour to saturated liquid. If the separation and reflux ratio remains unchanged, the number of ideal stages will (A) Increase (B) Decrease (C) Remain same (D) Depend on saturated boiling point; may increase or decrease

Description : The feed to fractionating column is changed from saturated vapour to saturated liquid. If the separation and reflux ratio remains unchanged, the number of ideal stages will (A) Increase (B) Decrease (C) Remain same (D) Depend on saturated boiling point; may increase or decrease

Last Answer : (A) Increase

Relative humidity is the ratio of actual vapour pressure to the saturation vapour pressure (A) At the same temperature (B) At the same pressure (C) In the same volume (D) In the atmosphere

Description : Relative humidity is the ratio of actual vapour pressure to the saturation vapour pressure (A) At the same temperature (B) At the same pressure (C) In the same volume (D) In the atmosphere

Last Answer : Answer: Option A

Pick up the correct statement from the following: (A) Absolute humidity at a given temperature is equal to weight of moisture present in a unit volume (B) Relative humidity is the ratio of actual vapour pressure and saturation vapour pressure at the same temperature (C) Relative humidity is the ratio of the weight of the vapours present per unit volume to the weight of vapours which could be contained at the same temperature when fully saturated (D) All the above

Description : Pick up the correct statement from the following: (A) Absolute humidity at a given temperature is equal to weight of moisture present in a unit volume (B) Relative humidity is the ratio of ... of vapours which could be contained at the same temperature when fully saturated (D) All the above

Last Answer : Answer: Option D

Pick out the wrong statement about nucleate boiling. (A) Bubble generation is by expansion of entrapped gas/vapour at small cavities in the surface (B) Surface temperature is greater than the saturation temperature of the liquid (C) Heat transfer from the surface of the liquid is less than that in film boiling (D) The temperature is less than that of film boiling

Description : Pick out the wrong statement about nucleate boiling. (A) Bubble generation is by expansion of entrapped gas/vapour at small cavities in the surface (B) Surface temperature is greater than the saturation ... less than that in film boiling (D) The temperature is less than that of film boiling

Last Answer : (D) The temperature is less than that of film boiling

The heating capacity of muffle furnace depends on the (A) Surface area & emissivity of the stock (B) Properties of the muffle wall (temperature, area, and emissivity) (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : The heating capacity of muffle furnace depends on the (A) Surface area & emissivity of the stock (B) Properties of the muffle wall (temperature, area, and emissivity) (C) Both (A) & (B) (D) Neither (A) nor (B)

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

The heating capacity of continuous reheating furnace depends upon the (A) Hearth area and furnace temperature (B) Emissivity of the stock (C) Ratio of wall surface to stock surface (D) All (A), (B) and (C)

Description : The heating capacity of continuous reheating furnace depends upon the (A) Hearth area and furnace temperature (B) Emissivity of the stock (C) Ratio of wall surface to stock surface (D) All (A), (B) and (C)

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

When vaporisation takes place directly at the heating surface, it is called (A) Film boiling (B) Nucleate boiling (C) Vapour binding (D) None of these

Description : When vaporisation takes place directly at the heating surface, it is called (A) Film boiling (B) Nucleate boiling (C) Vapour binding (D) None of these

Last Answer : (B) Nucleate boiling

Condensing film co-efficient for steam on horizontal tubes ranges from 5000 to 15000 Kcal/hr.m2 .°C. Condensation of vapor is carried out inside the tube in a shell and tube heat exchanger, when the (A) Higher condensing film co-efficient is desired (B) Condensate is corrosive in nature (C) Lower pressure drop through the exchanger is desired (D) Temperature of the incoming vapor is very high Answer: Option B

Description : Condensing film co-efficient for steam on horizontal tubes ranges from 5000 to 15000 Kcal/hr.m2 .°C. Condensation of vapor is carried out inside the tube in a shell and tube heat ... drop through the exchanger is desired (D) Temperature of the incoming vapor is very high

Last Answer : (B) Supersaturated