Heat and Mass Transfer Which of the following would lead to a reduction in thermal resistance? In radiation, increasing the temperature and reducing the emissivity. All of these In convection, stirring of the fluid and cleaning the heating surface. In conduction, reduction in the thickness of the material and an increase in thermal conductivity. In radiation, increasing the temperature and reducing the emissivity. All of these In convection, stirring of the fluid and cleaning the heating surface. In conduction, reduction in the thickness of the material and an increase in thermal conductivity. ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When absorptivity (α) = 1, reflectivity (ρ) = 0 and transmissivity (τ) = 0, then the body is said to be a Opaque body White body Grey body Black body Opaque body White body Grey body Black body 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 Radiation Conduction Convection Both convection and conduction Radiation Conduction Convection ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A steam pipe is to be insulated by two insulating materials put over each other. For best results Better insulation should be put over pipe and better one over it Whether to put inferior OIL over pipe or the better one would depend on steam temperature Both may be put in any order Inferior insulation should be put over pipe and better one over it Better insulation should be put over pipe and better one over it Whether to put inferior OIL over pipe or the better one would depend on steam temperature Both may be put in any order Inferior insulation should be put over pipe and better one over it ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Stefan Boltzmann law, the total radiation from a black body per second per unit area is directly proportional to the Cube of the absolute temperature Fourth power of the absolute temperature Square of the absolute temperature Absolute temperature Cube of the absolute temperature Fourth power of the absolute temperature Square of the absolute temperature Absolute temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In a shell and tube heat exchanger, baffles are provided on the shell side to Prevent stagnation of shell side fluid Provide support for tubes All of these Improve heat transfer Prevent stagnation of shell side fluid Provide support for tubes All of these Improve heat transfer ANSWER DOWNLOAD EXAMIANS APP