Vacuum is generally maintained in the vapour space of an evaporator mainly to__________________?

Related Mcqs:

For the same heat load and mass flow rate in the tube side of a shell and tube heat exchanger, one may use multipass on the tube side, because it__________________?

A. Decreases the pressure drop B. Decreases the outlet temperature of cooling medium C. Increases the overall heat transfer coefficient D. None of these...

A multiple effect evaporator as compared to a single effect evaporator of the same capacity has _________________?

A. Lower heat transfer area B. Lower steam economy C. Higher steam economy D. Higher solute concentration in the product...

Tube expansion allowances exist in _____________ heat exchanger?

A. Multipass fixed tube sheet B. U-tube C. Single pass fixed tube sheet D. None of these...

In a shell and tube heat exchanger, square pitch compared to triangular pitch__________________?

A. Gives a higher shell side pressure drop B. Gives a lower shell side pressure drop C. Can pack more surface area into a shell of given diameter D. None of these...

Thermal diffusivity of a material __________________?

A. Has the unit m2 /sec B. Is defined as K/ρ . Cp C. Is the ratio of thermal conductivity to thermal capacity D. All A., B. and C....