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 = 0.5 V cosα Vb = V cosα Vb = 0.5 V² cosα Vb = V² cosα Vb = 0.5 V cosα Vb = V cosα Vb = 0.5 V² cosα Vb = V² cosα ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines The impulse turbine rotor efficiency will have a maximum value of 0.5 cos 2α, where α is the nozzle exit flow angle, if the Blade solidity is 0.65 Blades are equiangular and frictionless Blades are equiangular Blade velocity coefficient is unity Blade solidity is 0.65 Blades are equiangular and frictionless Blades are equiangular Blade velocity coefficient is unity ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines The isentropic enthalpy drop in moving blade is two-third of the isentropic enthalpy drop in fixed blades of a turbine. The degree of reaction will be 1.67 0.4 0.56 0.67 1.67 0.4 0.56 0.67 ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines With increase in load, radiant superheater has Rising characteristic Flat characteristic Linear characteristic Drooping characteristic Rising characteristic Flat characteristic Linear characteristic Drooping characteristic ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines Incomplete combustion can be best judged by Excess air in flue gases Measuring carbon monoxide in flue gases Smoky chimney exit Measuring temperature of flue gases at exit of furnace Excess air in flue gases Measuring carbon monoxide in flue gases Smoky chimney exit Measuring temperature of flue gases at exit of furnace ANSWER DOWNLOAD EXAMIANS APP
Steam Boilers, Engines, Nozzles and Turbines The shell of the Cochran boiler is made hemispherical Both (A) and (B) To withstand the pressure of steam inside the boiler To give maximum space and strength None of these Both (A) and (B) To withstand the pressure of steam inside the boiler To give maximum space and strength None of these ANSWER DOWNLOAD EXAMIANS APP
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