Statement (I): Modern turbines have velocity compounding at the initial stages and pressure compounding in subsequent stages.
Statement (II): Excessive tip leakage occurs in the high-pressure region of reaction blading.

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ESE Mechanical 2014 Official Paper - 1

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Both statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
Both Statement (I) and Statement (II) are individually true but statement (II) is not the correct explanation of Statement (I)
Statement (I) is true but Statement (II) is false
Statement (I) is false but Statement (II) is true

Answer 1

Explanation:

Modern turbines have velocity compounding at the initial stages and pressure compounding in subsequent stages.
This is due to fact that there is a high enthalpy drop in velocity compounding turbine (one 2 row Curtis stage is equivalent to eight 50% reaction), two single-stage impulse turbines and also there is higher density of steam. Hence statement I is true.
Now, statement II says excessive tip leakage occurs in the high-pressure region of reaction blading i.e. at the Curtis stage, which is also true but along with it there is another cause also which is having all pressure stages or reaction stages, the length and size of the turbine become very large which eventually increases the cost of the turbine.

Since both the assertion and reason are individually correct but the reason is not the only or main cause, so the correct option is option (2).