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
0.4
0.56
0.67
1.67
Correct Answer :
A. 0.4
Related Questions
The diameter of flue tube in a Cornish boiler is _________ that of the shell.
One-fourth
One-third
Two-fifth
Three-fifth
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Does not change
Increases
Decreases
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Work done during adiabatic expansion
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Superheated steam
Cushion steam
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15 to 25 %
25 to 40 %
40 to 60 %
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130 mm
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The cost of the engine, for the same power and economy, is more than that of a simple steam engine.
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The ratio of expansion is reduced, thus reducing the length of stroke.
The temperature range per cylinder is increased, with corresponding increase in condensation.
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If partial pressure of air and steam be pa and ps respectively in a condenser, then according to Dalton's law, the pressure in condenser is equal to
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Which of the following statement is correct for steam turbines as compared to reciprocating steam engines?
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Increases
Decreases
Does not effect
None of these
A double acting steam engine with a cylinder diameter of 190 mm and a stroke of 300 mm has a cut-off of 0.35. The expansion ratio for this engine is nearly
1.05
2.86
6.65
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Pulverised coal
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Blade velocity coefficient is unity
Blades are equiangular and frictionless
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Two
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Indicated thermal efficiency
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Steam turbine
Steam condenser
Steam injector
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Tandem type compound engine
Woolf type compound engine
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More than
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