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'

1 Answer

Answer :

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

Related questions

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

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

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

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

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Last Answer : (A) < 1

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Description : In a co-current double pipe heat exchanger used for condensing saturated steam over the inner tube, if the entrance and exit conditions of the coolant are interchanged, then the rate of condensation ... Decrease (C) Remain unchanged (D) Either increase or decrease; depends on the coolant flow rate

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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

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