Heat and Mass Transfer In heat exchangers, degree of approach is defined as the difference between temperatures of Cold water inlet and outlet Hot medium inlet and outlet Hot medium outlet and cold water inlet Hot medium outlet and cold water outlet Cold water inlet and outlet Hot medium inlet and outlet Hot medium outlet and cold water inlet Hot medium outlet and cold water outlet ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass 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 Both convection and conduction Convection Radiation Conduction Both convection and conduction Convection Radiation Conduction ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The amount of heat flow through a body by conduction is Directly proportional to the surface area of the body Directly proportional to the temperature difference on the two faces of the body All of these Dependent upon the material of the body Directly proportional to the surface area of the body Directly proportional to the temperature difference on the two faces of the body All of these Dependent upon the material of the body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Reynolds number (RN) is given by (where h = Film coefficient, l = Linear dimension, V = Velocity of fluid, k = Thermal conductivity, t = Temperature, ρ = Density of fluid, cp = Specific heat at constant pressure, and μ = Coefficient of absolute viscosity) RN = V²/t.cp RN = hl/k RN = μ cp/k RN = ρ V l /μ RN = V²/t.cp RN = hl/k RN = μ cp/k RN = ρ V l /μ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two plates spaced 150 mm apart are maintained at 1000°C and 70°C. The heat transfer will take place mainly by Free convection Radiation Convection Forced convection Free convection Radiation Convection Forced convection ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Prevost theory of heat exchange All bodies above absolute zero emit radiation Heat transfer in most of the cases takes place by combination of conduction, convection and radiation Heat transfer by radiation requires no medium It is impossible to transfer heat from low temperature source to t high temperature source All bodies above absolute zero emit radiation Heat transfer in most of the cases takes place by combination of conduction, convection and radiation Heat transfer by radiation requires no medium It is impossible to transfer heat from low temperature source to t high temperature source ANSWER DOWNLOAD EXAMIANS APP
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