(SEM III) THEORY EXAMINATION 2023-24 FLUID MECHANICS & FLUID MACHINES

This question paper is designed to assess the student’s understanding of Fundamental Fluid Mechanics Principles and Fluid Machines, including flow behavior, boundary layers, pumps, turbines, and hydraulic systems. The paper evaluates theoretical knowledge, mathematical derivations, and problem-solving skills required in mechanical engineering.

The entire exam is divided into three structured sections, ensuring a balanced evaluation of conceptual clarity, numerical ability, and analytical thinking.

SECTION A — Short Conceptual Questions (14 Marks)

Section A contains 7 short-answer questions, each of 2 marks, focusing on basic definitions, differences, and fundamental concepts related to:

Fluid properties such as specific weight, specific gravity

Flow characteristics including laminar vs turbulent flow and rotational vs irrotational flow

Important dimensionless numbers such as Reynolds number

Basic pump parameters like mechanical efficiency and slip in reciprocating pumps

Discharge coefficients (Cc, Cv) for measuring instruments

This section checks the student’s foundational understanding and ability to recall key concepts concisely.

SECTION B — Descriptive & Analytical Questions (21 Marks)

Students must attempt any three out of five questions, each carrying 7 marks.
This section tests deeper understanding, derivation skills, and the ability to explain concepts with clarity.
Topics include:

Working principle and derivation of discharge formula for Venturimeter

Continuity equation and types of flows (steady vs unsteady)

Boundary layer velocity profile and computation of displacement & momentum thickness

Detailed derivation and velocity triangles for the Pelton Wheel and its maximum efficiency

Concept & importance of air vessels in reciprocating pumps

Numerical problems, derivations, and theoretical explanations are expected in this section.

SECTION C — Long Analytical / Application-Based Questions (35 Marks)

Section C consists of 5 sets, each containing two options. Students must attempt one question from each set, making a total of 5 long-answer questions, each worth 7 marks.

These questions are designed to evaluate:

Problem-solving with viscosity, shear stress, and fluid motion

Application of continuity equation in piping networks

Understanding of boundary layer separation, velocity distribution in pipes, and pressure gradients

Advanced turbine problems involving velocity diagrams, flow rate, and power calculations

Concept of cavitation, its harmful effects, and preventive methods

Difference between centrifugal and reciprocating pumps, indicator diagrams, and work calculations

This section assesses the student’s ability to apply theoretical knowledge to engineering problems.

Additional 2–3 Questions Added (As Requested)

To make the paper more comprehensive, you may include the following:

SECTION A (Additional Questions)

h. Define hydraulic gradient line (HGL) and total energy line (TEL).
i. What is cavitation number?

SECTION B (Additional Question)

f. Explain Bernoulli’s equation along a streamline and discuss its practical applications in fluid systems.

SECTION C (Additional Question)

c. Derive Euler’s equation for fluid motion and explain each term in detail.

Overall Purpose of This Question Paper

This question paper aims to:

Test the student's ability to analyze fluid behavior under different flow conditions

Evaluate derivation skills and theoretical understanding of pumps and turbines

Assess numerical accuracy and practical engineering applications

Strengthen fundamentals necessary for advanced subjects like CFD, Hydraulics, and Turbo Machines

It ensures that mechanical engineering students develop the required competency in both fluid mechanics theory and fluid machine applications.