Pick out the wrong statement?
A backward feed multiple effect evaporator is better than forward feed for concentrating cold feed, because it provides __________?
For evaporation of viscous solution in a multiple effect evaporator, the preferred feeding scheme is __________?
1000 Kg of liquid at 30°C in a well stirred vessel has to be heated to 120°C, using immersed coils carrying condensing steam at 150°C. The area of the steam coils is 1.2 m2 and the overall heat transfer co-efficient to the liquid is 1500 W/m2.°C. Assuming negligible heat loss to the surrounding and specific heat capacity of the liquid to be 4 kJ/kg.°C, the time taken for the liquid to reach desired temperature will be__________?
Heat waves__________?
If air (a non-condensing gas) is present in a condensing vapor stream, it will __________ the condensation rate of vapor?
For a perfectly transparent surface (like gases), the__________?
A fluid is flowing inside the inner tube of a double pipe heat exchanger with diameter ‘d’. For a fixed mass flow rate, the tube side heat transfer co-efficient for turbulent flow conditions is proportional to__________?
Heat transfer co-efficient (h) for a fluid flowing inside a clean pipe is given by h = 0.023 (K/D) (DVρ/μ)0.8 (CP.μ/k)0.4. This is valid for the value of NRe equal to__________?
The ratio of kinematic viscosity to thermal diffusivity is called the __________ number?
Vibrations in the tubes of a shell and tube heat exchanger is induced due to the __________?
What is the steam economy in case of a single effect evaporator system ?
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__________?
Baffles in the shell side of a shell and tube heat exchanger ?
__________ chart is known as transient heat conduction chart?
Controlling heat transfer film co-efficient is the one, which offers __________ resistance to heat transfer?
Which of the following is concerned with both heat and mass transfer ?
Duhring‟s rule is important in solving problems on__________?
Heat transfer by radiation between two bodies at T1 & T2 and in an ambient temperature of Ta°C depends on__________?
The film thickness for laminar film condensation on vertical surface __________ from top to bottom?
__________ paint has the minimum absorption co-efficient?
For shell and tube heat exchanger, with increasing heat transfer area, the purchased cost per unit heat transfer area__________?
Mode of heat transfer in which the fluid moves under the influence of changes in fluid pressure produced by external work is called__________?
Steam traps are provided in steam carrying pipelines to__________?
Kirchoff‟s law applies to __________ radiation?
Log mean temperature difference (LMTD) cannot be used, if __________?
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__________?
Bulk of the convective heat transfer resistance from a hot tube surface to the fluid flowing in it, is __________?
If Prandtl number is greater than the Schmidt number, then the__________?
Thermal diffusivity is the most important in heat transfer by__________?
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 __________?
The statement that “maximum wavelength of radiation is inversely proportional to the temperature” is __________ law?
Among liquids, water has a comparatively high value of thermal conductivity, due to its__________?
In which mode of heat transfer, the Biot number is important ?
A diathermanous substance __________ the thermal radiation completely?
Boiling point elevation of a solution of NaOH __________?
Radiant energy received by a body is proportional to (where, d = the distance between the object emitting radiation and that receiving it.) ?
Overall thermal resistance for conductive heat transfer through a series of flat resistances is equal to the__________?
Prandtl and Reynolds analogy are same, when Prandtl number is__________?
Arithmetic mean area can be used in heat transfer problem to calculate the heat flow by conduction through a cylinder which is __________?
jH factor for heat transfer is not a function of the __________ number?
In a heat exchanger, one transfer unit means__________?
A 2-4 heat exchanger involves__________?
In a shell and tube heat exchanger, the height of 25 percent cut baffles is equal to (where, D = inside diameter of shell) ?
Latent heat absorbed by 1 lb of water at 212°F, when it is changed to steam at 212°F, may be around __________ BTU?
Baffle spacing __________?
The local surface conductance for laminar film condensation on vertical surface is (where, t = film thickness) __________?
The purpose of floating head in a heat exchanger is to__________?
Mechanical recompression evaporation is used in the production of__________?
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__________?
The Fourier number (defined as a.t/L2) is used in the analysis of problem involving heat transfer by__________?

Pick out the wrong statement ?

A. In case of heat transfer by purely forced convection, GR/Re 2 ≤ 1
B. The equivalent diameter of heat transfer for a duct of square cross-section (having each side as
‘x’) is equal to 4x
C. Distillation process is not the same as evaporation
D. The effectiveness of nucleate boiling depends basically on the ease with which the bubbles are
formed and detached from the heating surface

Correct Answer: B. The equivalent diameter of heat transfer for a duct of square cross-section (having each side as
‘x’) is equal to 4x ✔

Last Updated: March 03, 2019