Hydraulic Machines MCQ with answer and solution

Concept

Classification of Francis turbine

Formula

NONE

Step-by-step solution

1. Francis turbine is a reaction turbine in which water enters the runner radially inwards and leaves in the radial or axial direction. 2. Historically and in classical classification, it is characterized as an inward flow reaction turbine with radial discharge at the outlet. 3. Therefore, it is classified as an inward flow reaction turbine having radial discharge at outlet. Answer: B

Explanation

A Francis turbine is a reaction turbine where water enters the runner radially inwards and leaves axially or radially at the outlet, typically classified as an inward flow reaction turbine with radial discharge at the outlet. This configuration allows it to efficiently extract hydraulic energy across medium heads.

Why the other options are wrong

A) Tangential flow impulse turbine describes a Pelton wheel turbine. C) Axial flow reaction turbine describes a Kaplan or Propeller turbine. D) Option B is correct because a Francis turbine is an inward flow reaction turbine with radial discharge at the outlet.

Shortcut

Francis turbine = Inward radial reaction turbine ("Francis Inward Reaction").

Common mistake

Confusing a Francis turbine with a tangential flow impulse turbine like Pelton or an axial flow turbine like Kaplan.