Heat Transfer Which of the following situations can be approximated to a steady state heat transfer system? Boiling brine kept in open vessel when the bottom surface temperature of the vessel is maintained constant at 180°C A red hot steel slab (having outside surface temperature as 1300°C) exposed to the atmosheric air at 35°C 10 kg of dry saturated steam at 8 kgf/cm² flowing through a short length of stainless steel pipe exposed to atmospheric air at 35°C A sub-cooled refrigerant liquid at 8°C flowing at the rate of 6 Kg/minute through a copper pipe exposed to atmospheric air at 35°C Boiling brine kept in open vessel when the bottom surface temperature of the vessel is maintained constant at 180°C A red hot steel slab (having outside surface temperature as 1300°C) exposed to the atmosheric air at 35°C 10 kg of dry saturated steam at 8 kgf/cm² flowing through a short length of stainless steel pipe exposed to atmospheric air at 35°C A sub-cooled refrigerant liquid at 8°C flowing at the rate of 6 Kg/minute through a copper pipe exposed to atmospheric air at 35°C ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Multipass heat exchangers are used To obtain higher heat transfer co-efficient and shorter tube Because of simplicity of fabrication For low heat load To reduce the pressure drop To obtain higher heat transfer co-efficient and shorter tube Because of simplicity of fabrication For low heat load To reduce the pressure drop ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer A hollow sphere and a solid sphere of the same material and equal radii are heated to the same temperature. In this case, The cooling rate will be the same for the two spheres and hence the two spheres will have equal temperatures at any instant Both B & C Both the spheres will emit equal amount of radiation per unit time in the beginning Both will absorb equal amount of radiation from the surrounding in the beginning The cooling rate will be the same for the two spheres and hence the two spheres will have equal temperatures at any instant Both B & C Both the spheres will emit equal amount of radiation per unit time in the beginning Both will absorb equal amount of radiation from the surrounding in the beginning ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Which of the following has the lowest Prandtl number? Molten sodium (a coolant used in fast breeder reactor) Transformer oil Dilute H₂SO₄ Water Molten sodium (a coolant used in fast breeder reactor) Transformer oil Dilute H₂SO₄ Water ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Absorptivity and refletivity of a perfect black body are respectively 1 and 0 1 and ? 0 and 0.5 0 and 1 1 and 0 1 and ? 0 and 0.5 0 and 1 ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Nucleate boiling is promoted In the absence of agitation On rough surfaces On polished surfaces None of these In the absence of agitation On rough surfaces On polished surfaces None of these ANSWER DOWNLOAD EXAMIANS APP