Home
About Us
Contact Us
Privacy Policy
Search
Home
→
Chemical Heat Transfer
→
In the free convection regime of pool boiling, the heat flux is proportional to__________________?
Related MCQs
Prandtl number is the ratio of__________?
Prandtl number is given by__________?
Trap is used to remove __________ from steam pipe lines?
Wavelength corresponding to the maximum energy is inversely proportional to the absolute temperature. This is __________ law?
Economy of a multiple effect evaporator depends upon the __________?
A wall has two layers of materials A and B; each made of a different material. Both the layers have the same thickness. The thermal conductivity of material A is twice that of B. Under the equilibrium, the temperature difference across the wall is 36°C. The temperature difference across the layer A is __________ °C?
Temperature profile in steady state heat transfer is__________?
Maximum water velocity in tubes of a 1-2 shell and tube heat exchanger may be around __________ metres/second?
A tank painted with which of the following coloured paints, would heat up maximum by radiation from sun ?
Three materials A, B and C of equal thickness and of thermal conductivity of 20, 40 & 60 kcal/hr. m. °C respectively are joined together. The temperature outside of A and C are 30°C and 100°C respectively. The interface between B and C will be at a temperature of __________ °C?
The thermal radiation emitted by a body is proportional to Tn, where T is its absolute temperature. The value of ‘n’ is exactly 4 for__________?
Evaporation by thermo compression results in the __________?
Use of transverse baffles in a shell and tube heat exchanger is done to increase the__________?
Which of the following situations can be approximated to a steady state heat transfer system ?
Heat transfer by __________ may not necessarily require the presence of a medium?
Nusselt number is the ratio of the __________?
Prandtl number is the reciprocal of__________?
For a multipass shell and tube heat exchanger, the LMTD correction factor is always__________?
Thermal conductivity of a gas at low density, __________ with increase in temperature ?
The interchange factor for radiation heat transfer from surface ‘x’ to surface ‘y’ in case of an infinite parallel planes with emissivities εx & εy is given by__________?
With increase in temperature, the thermal conductivity of a gas __________?
Which area is used in case of heat flow by conduction through a cylinder ?
The rate of emission of radiation by a body does not depend upon the__________?
In a cooling tower, water becomes cool by__________?
Out of the following four assumptions used in the derivation of the equation for LMTD [LMTD = (Δt1 – Δt2)/ln(Δt1/Δt2)], which one is subject to the largest deviation in practice ?
What is the logarithmic mean of r1 and r2 ?
The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe, where the wall heat flux is constant, is__________?
The overall resistance for heat transfer through a series of flat resistance, is the __________ of the resistances?
Heat transfer co-efficient equation for forced convection, Nu = 0.023 Re 0.8. Pr n, is not valid, if the value of __________?
An ejector is used to__________?
In a laboratory test run, the rate of drying was found to be 0.5 x 10-3 kg/m2.s, when the moisture content reduced from 0.4 to 0.1 on dry basis. The critical moisture content of the material is 0.08 on a dry basis. A tray dryer is used to dry 100 kg (dry basis) of the same material under identical conditions. The surface area of the material is 0.04 m2/kg of dry solid. The time required (in seconds) to reduce the moisture content of the solids from 0.3 to 0.2 (dry basis) is__________?
Peclet number (Pe) is given by__________?
In Fourier’s law, the proportionality constant is called the__________?
When the ratio of the Grashoff number and to the square of Reynolds number is one, the dominant mechanism of heat transfer is __________?
The units of resistance to heat transfer is __________?
For hot feed, forward feeding as compared to backward feeding results in __________ economy?
In sub-cooled boiling ?
Heat transfer by conduction results due to the transfer of free electrons, kinetic energy & vibrational energy from one molecule to another. Conduction heat transfer cannot take place__________?
The thickness of condensate layer in filmwise condensation depends on the__________?
The heat transfer co-efficient in film type condensation is __________ that for dropwise condensation?
Steam economy in case of a triple effect evaporator will be __________?
In a forward feed multiple effect evaporator unit__________?
Dropwise condensation is promoted on a/an __________ surface?
Which of the following parameters of the fluid is not very important, while deciding its route in a shell and tube heat exchanger ?
It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of vaporisation is 2100 kJ/kg and the specific heat of the solution is 4 kJ/kg.K. The rate at which the heat has to be supplied in (kJ/min) to the evaporator is__________?
Fqra cold viscous feed, backward feed gives __________ than forward feed?
The Graetz number is concerned with the__________
The unit of conductance in SI unit is__________?
Which of the following has the lowest Prandtl number ?
In case of a multipass shell and tube heat exchanger, the temperature drop in the fluid __________?
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__________ ?
In the free convection regime of pool boiling, the heat flux is proportional to__________________?
A. Δt1/2
B. Δt2
C. Δt5/4
D. Δt
Correct Answer:
Δt5/4
✔
Last Updated:
March 03, 2019