MCQ Questions and Answers on Turbo Machines

Q.

Cavitation in a centrifugal pump is likely to occur at the

A. Impeller exit

B. Impeller inlet

C. Diffuser exit

D. Involute casing

Discuss

Answer : Option:- B

Explanation :

Cavitation in a centrifugal pump is likely to occur at the impeller inlet.

Q.

The use of a draft tube in a reaction type water turbine helps to

A. Prevent air from entering

B. Increase the flow rate

C. Convert the kinetic energy to pressure energy

D. Eliminate eddies in the downstream

Discuss

Answer : Option:- C

Explanation :

At the exit of reaction turbines, a pipe of gradually increasing cross-sectional area known as draft tube. It is used to permit negative suction head by having the capability of converting kinetic energy of water into pressure head, thus increasing the power capacity of turbine system.

Q.

Which one of the following is not correct regarding both Kaplan and propeller turbines?

A. The runner is axial

B. The blades are wing type

C. There are four to eight blades

D. The blades can be adjusted

Discuss

Answer : Option:- D

Explanation :

Blades can be adjusted only in case of Kaplan turbine.

Q.

Kaplan turbine is

A. A high head mixed flow turbine

B. A low axial flow turbine

C. An outward flow reaction turbine

D. An impulse inward flow turbine

Discuss

Answer : Option:- A

Explanation :

Kaplan turbine is a highly efficient mixed flow reaction turbine with adjustable blades and adjustable wicket gates. It is used with low head high discharge specifications.

Q.

Priming is necessary in

A. Centrifugal pumps to lift water from a greater depth

B. Centrifugal pumps to remove air in the suction pipe and casing

C. Hydraulic turbine to remove air in the turbine casing

D. Hydraulic turbine to increase the speed of turbine and to generate more power

Discuss

Answer : Option:- B

Explanation :

Priming is done in centrifugal pump operation in which suction pipe, casing and portion up to delivery pipe are completely filled with the same liquid to be lifted such that no air pocket is left and then the delivery valve is closed.

Q.

A centrifugal pump gives maximum efficiency when its blades are

A. Bent forward

B. End backward

C. Bent backward

D. Wave shaped

Discuss

Answer : Option:- C

Explanation :

Maximum efficiency can be obtained when blades are bent backward.

Q.

Why is a minimum of Net Positive Suction Head (NPSH) required for a hydraulic pump?

A. To prevent cavitation

B. To increase discharge

C. To increase suction head

D. To increase efficiency

Discuss

Answer : Option:- A

Explanation :

Minimum NPSH is required in centrifugal pumps to prevent cavitation.

MCQ Questions and Answers on Turbo Machines

Q. Cavitation in a centrifugal pump is likely to occur at the

Q. The use of a draft tube in a reaction type water turbine helps to

Q. Which one of the following is not correct regarding both Kaplan and propeller turbines?

Q. Kaplan turbine is

Q. Priming is necessary in

Q. A centrifugal pump gives maximum efficiency when its blades are

Q. Why is a minimum of Net Positive Suction Head (NPSH) required for a hydraulic pump?

Q.

Cavitation in a centrifugal pump is likely to occur at the

Q.

The use of a draft tube in a reaction type water turbine helps to

Q.

Which one of the following is not correct regarding both Kaplan and propeller turbines?

Q.

Kaplan turbine is

Q.

Priming is necessary in

Q.

A centrifugal pump gives maximum efficiency when its blades are

Q.

Why is a minimum of Net Positive Suction Head (NPSH) required for a hydraulic pump?