Mechanical Engineering - Hydraulic Machines - Discussion
Discussion Forum : Hydraulic Machines - Section 1 (Q.No. 1)
1.
Power required to drive a centrifugal pump is directly proportional to __________ of its impeller.
Discussion:
34 comments Page 3 of 4.
Indrajeet said:
8 years ago
According to affinity law of pump.
Power is directly proportional to the fifth Power of diameter.
Power is directly proportional to the fifth Power of diameter.
Vinit said:
8 years ago
The Correct answer will be d^5.
Jigar k patel said:
8 years ago
Correct Ans is C.
Law 2c Power is proportional to the cube of impeller diameter (assuming constant shaft speed):
{\displaystyle {P_{1} \over P_{2}}={\left({D_{1} \over D_{2}}\right)^{3}}} {P_{1} \over P_{2}}={\left({D_{1} \over D_{2}}\right)^{3}}.
Law 2c Power is proportional to the cube of impeller diameter (assuming constant shaft speed):
{\displaystyle {P_{1} \over P_{2}}={\left({D_{1} \over D_{2}}\right)^{3}}} {P_{1} \over P_{2}}={\left({D_{1} \over D_{2}}\right)^{3}}.
Pabitra said:
8 years ago
Fifth power of diameter will be the correct answer.
Manish said:
8 years ago
Note that there are two sets of affinity laws:.
Affinity laws for a specific centrifugal pump - to approximate head, capacity and power curves for different motor speeds and /or different diameter of impellers.
Affinity laws for a family of geometrically similar centrifugal pumps - to approximate head, capacity and power curves for different motor speeds and /or different diameter of impellers.
Affinity laws for a specific centrifugal pump - to approximate head, capacity and power curves for different motor speeds and /or different diameter of impellers.
Affinity laws for a family of geometrically similar centrifugal pumps - to approximate head, capacity and power curves for different motor speeds and /or different diameter of impellers.
Sharan said:
8 years ago
Ans: C is correct.
i.e d^3--p=TW=(Tou*pi*d^3/16*T)*(v/r).
i.e d^3--p=TW=(Tou*pi*d^3/16*T)*(v/r).
Pushpender said:
8 years ago
Affinity laws applied to axial and radial flows pumps and turbines. Its a tangent flow ; impulse turbine so I think 4th power is correct.
Sandeep said:
7 years ago
d^4 will be the correct answer. Since the question is asked as directly proportional the tangent flow of an impulse turbine always takes 4th power to diameter.
(2)
Sullahe sanu said:
7 years ago
d^4 is the answer.
Deepak Rathva said:
7 years ago
The Correct answer is D^5.
Ref: R.K.Bansal.
Ref: R.K.Bansal.
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