A. Minimum
B. Maximum
C. Zero
D. Infinity
Related Mcqs:
- 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 - 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 - 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) - 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. ∞ - 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. - 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 - 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 - 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 - For a counter current heat exchanger with Ti h = 80°C, T°c = 60°C, T°h = 50°C and Ti c = 30°C, and the temperature difference between the two streams being the same everywhere along Z, the direction of flow of hot fluid. The temperature profile should satisfy___________________?
A. d2T/dZ2 > 0
B. d2T/dZ2 = 0
C. d2T/dZ2 < 0
D. dT/dZ = 0 - Air is to be heated by condensing steam. Two heat exchangers are available (i) a shell and tube heat exchanger and (ii) a finned tube heat exchanger. Tube side heat transfer area are equal in both the cases. The recommended arrangement is________________?
A. Finned tube heat exchanger with air inside and steam outside
B. Finned tube heat exchanger with air outside and steam inside
C. Shell and tube heat exchanger with air inside tubes and steam on shell side
D. Shell and tube heat exchanger with air on shell side and steam inside tubes
