Steam Boilers, Engines, Nozzles and Turbines It is required to produce large amount of steam at low pressure. Which boiler should be used? Cochran boiler Babcock and Wilcox boiler Pulverized fuel fired boiler Lancashire boiler Cochran boiler Babcock and Wilcox boiler Pulverized fuel fired boiler Lancashire boiler ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines The velocity of steam leaving the nozzle (V) is given by (where K = Nozzle coefficient or nozzle efficiency, and hd = Enthalpy or heat drop during expansion of steam in a nozzle) V = 44.72 K hd V = 44.72 K hd V = 44.72 hd K V = 44.72 K hd V = 44.72 K hd V = 44.72 K hd V = 44.72 hd K V = 44.72 K hd ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines The crown of the fire box is made hemispherical in order to Withstand pressure inside boiler Give maximum strength Give maximum space Resist intense heat in fire box Withstand pressure inside boiler Give maximum strength Give maximum space Resist intense heat in fire box ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines In an ideal impulse turbine, the Axial velocity at inlet is equal to that at the outlet Whirl velocity at inlet is equal to that at the outlet Absolute velocity at the inlet of moving blade is equal to that at the outlet Relative velocity at the inlet of the moving blade is equal to that at the outlet Axial velocity at inlet is equal to that at the outlet Whirl velocity at inlet is equal to that at the outlet Absolute velocity at the inlet of moving blade is equal to that at the outlet Relative velocity at the inlet of the moving blade is equal to that at the outlet ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines With increase in load, radiant superheater has Linear characteristic Rising characteristic Flat characteristic Drooping characteristic Linear characteristic Rising characteristic Flat characteristic Drooping characteristic ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines The efficiency of an impulse turbine is maximum when (where Vb = Blade speed, V = Absolute velocity of steam entering the blade, and α = Nozzle angle) Vb = V² cosα Vb = V cosα Vb = 0.5 V cosα Vb = 0.5 V² cosα Vb = V² cosα Vb = V cosα Vb = 0.5 V cosα Vb = 0.5 V² cosα ANSWER DOWNLOAD EXAMIANS APP
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