Heat Transfer At what value of Prandtl number, the hydrodynamic and thermal boundary layers are identical? 0.5 1.5 1 80 0.5 1.5 1 80 ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Condensing film co-efficient for steam on horizontal tubes ranges from 5000 to 15000 Kcal/hr.m² .°C. Condensation of vapor is carried out inside the tube in a shell and tube heat exchanger, when the Lower pressure drop through the exchanger is desired Higher condensing film co-efficient is desired Temperature of the incoming vapor is very high Condensate is corrosive in nature Lower pressure drop through the exchanger is desired Higher condensing film co-efficient is desired Temperature of the incoming vapor is very high Condensate is corrosive in nature ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer A steel sphere of radius 0.1 m at 400°K is immersed in an oil at 300°K. If the centre of the sphere reaches 350°K in 20 minutes, how long will it take for a 0.05 m radius steel sphere to reach the same temperature (at the centre) under identical conditions ? Assume that the conductive heat transfer co-efficient is infinitely large. 20 minutes 40 minutes 10 minutes 5 minutes 20 minutes 40 minutes 10 minutes 5 minutes ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Multipass heat exchangers are used To obtain higher heat transfer co-efficient and shorter tube For low heat load To reduce the pressure drop Because of simplicity of fabrication To obtain higher heat transfer co-efficient and shorter tube For low heat load To reduce the pressure drop Because of simplicity of fabrication ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer For turbulent flow in a tube, the heat transfer co-efficient is obtained from the Dittus-Boelter correlation. If the tube diameter is halved and the flow rate is doubled, then the heat transfer co-efficient will change by a factor of 1 37 6.1 1.74 1 37 6.1 1.74 ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer In Joule's experiment, an insulated container contains 20 kg of water initially at 25°C. It is stirred by an agitator, which is made to turn by a slowly falling body weighing 40 kg through a height of 4 m. The process is repeated 500 times. The acceleration due to gravity is 9.8 ms⁻². Neglecting the heat capacity of agitator, the temperature of water (in °C) is 25 34.4 40.5 26.8 25 34.4 40.5 26.8 ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS