Heat is transferred by conduction, convection and radiation in

Related MCQs

• Heat is transferred by all three modes of transfer, viz, conduction, convection and radiation in
• 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
• Extended heat transfer surface like fins are used to increase the heat transfer rate. Fin efficiency is defined as the ratio of heat transferred across the fin surface to the theoretical heat transfer across an equal area held at the
• With increase in the distance between the heat source and the object receiving the heat, the radiation heat transfer
• In convection heat transfer from hot flue gases to water tube, even though flow may be turbulent, a laminar flow region (boundary layer of film) exists close to the tube. The heat transfer through this film takes place by
• Resistance to heat flow by conduction is proportional to (where, t & ρ are thickness & density of the material respectively and A = area normal to the direction of heat flow.)
• A dimensionless number which is the ratio of mass heat flow rate to the heat flow rate by conduction under a unit temperature gradient and through a thickness L is known as
• 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
• In case of heat flow by conduction for a cylindrical body with an internal heat source, the nature of temperature distribution is
• In case of heat transfer by conduction in a hollow cylinder, __________ mean area is used to calculate the heat transfer rate.