Chemical Heat Transfer

Radiation energy is emitted by all the substances, which are above____________________?

Byadmin March 2, 2019August 24, 2021

Radiation energy is emitted by all the substances, which are above____________________?

A. 0°K
B. 0°C
C. 100°C
D. Room temperature

Chemical Heat Transfer

Peclet number (Pe) is given by____________________?

Peclet number (Pe) is given by____________________?

A. Pe = Re.Pr
B. Pe = Re/Pr
C. Pe = Pr/Re
D. Pe = Nu.Re

Read More Peclet number (Pe) is given by____________________?
Chemical Heat Transfer

Grashoff number, which is defined as g . β (Ts – T∞) ρ2. L3/μ2, is proportional to the ratio of buoyancy force to ____________ force?

Grashoff number, which is defined as g . β (Ts – T∞) ρ2. L3/μ2, is proportional to the ratio of buoyancy force to ____________ force?

A. Viscous
B. Elastic
C. Inertial
D. None of these

Read More Grashoff number, which is defined as g . β (Ts – T∞) ρ2. L3/μ2, is proportional to the ratio of buoyancy force to ____________ force?
Chemical Heat Transfer

Steam side heat transfer co-efficient in an evaporator is in the range of ______________ kcal/hr.m2°C?

Steam side heat transfer co-efficient in an evaporator is in the range of ______________ kcal/hr.m2°C?

A. 10-50
B. 100-500
C. 1000-1500
D. 5000-15000

Read More Steam side heat transfer co-efficient in an evaporator is in the range of ______________ kcal/hr.m2°C?
Chemical Heat Transfer

The absorptivity of a grey body at a given temperature _____________ with increasing wavelength of radiation?

The absorptivity of a grey body at a given temperature _____________ with increasing wavelength of radiation?

A. Increases
B. Decreases
C. Remain constant
D. May increase or decrease; depends on the material

Read More The absorptivity of a grey body at a given temperature _____________ with increasing wavelength of radiation?
Chemical Heat Transfer

Double pipe heat exchangers are preferably useful, when____________________?

Double pipe heat exchangers are preferably useful, when____________________?

A. High viscosity liquid is to be cooled
B. Requirement of heat transfer area is low
C. Overall heat transfer co-efficient is very high
D. A corrosive liquid is to be heated

Read More Double pipe heat exchangers are preferably useful, when____________________?
Chemical Heat Transfer

A perfect black body is a perfect _____________ of radiation?

A perfect black body is a perfect _____________ of radiation?

A. Absorber
B. Emitter
C. Both A. & B.
D. Neither A. nor B.

Read More A perfect black body is a perfect _____________ of radiation?