Question:-
Which one of the following relationship between angle of fixed blades and moving blades corresponds to that of parson’s turbine
Option (A)
a1 = a2
Option (B)
a1 = b2
Option(C)
a2 = b2
Option(D)
b1 = b2
Correct Option:
(B)
Question Solution:


Degree of reaction = (1/2) (Cf/Cb) (tan b1 + tan b2)
For 50% reaction balding
0.5 = (1/2)(Cf/Cb) (tan b 1 + tan b2 ....(1)
From velocity triangle, we have
(Cb/Cf) = tana1 + tanb1..... (2)
(Cb/Cf) = tana2 + tanb2 .....(3)
a1= b2 and b1 =a2
question-answer-faq-2829