What is the optimum blade speed ratio for maximum blade efficiency in a multi-stage turbine? (n denotes the number of moving blade rows in series)

What is the optimum blade speed ratio for maximum blade efficiency in

1.	What is the optimum blade speed ratio for maximum blade efficiency in a multi-stage turbine? (n denotes the number of moving blade rows in series)
A.	\(\frac{cos⁡α}{2*n} \)
B.	\(\frac{cos⁡β}{2*n} \)
C.	\(\frac{2*cos ⁡α}{n} \)
D.	\(\frac{2*cos β}{n} \)
Answer» B. \(\frac{cos⁡β}{2*n} \)

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What is the optimum blade speed ratio for maximum blade efficiency in a multi-stage turbine? (n denotes the number of moving blade rows in series)

What is the optimum blade speed ratio for maximum blade efficiency in a multi-stage turbine? (n denotes the number of moving blade rows in series)

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