Fluid Mechanics II

Code:

L.EM023

Acronym:

MF II

Keywords
Classification	Keyword
OFICIAL	Fluids and Energy

Instance: 2022/2023 - 1S

Active?	Yes
Responsible unit:	Fluids and Energy Division
Course/CS Responsible:	Bachelor in Mechanical Engineering

Cycles of Study/Courses

Acronym	No. of Students	Study Plan	Curricular Years	Credits UCN	Credits ECTS	Contact hours	Total Time
L.EM	217	Syllabus	3	-	6	52	162

Teaching language

Portuguese

Objectives

Analyse, understand and characterize the behaviour of internal flows, the energetic needs of a fluid flow and the functioning of centrifugal pumps and fans, the measurement of fundamental quantities in fluid flows, the interaction between a moving fluid and an immersed body and some fundamental aspects of compressible flows, in view of solving problems of fluid mechanics in engineering.

Learning outcomes and competences

It is expected that, at the end of the semester, students will be able to/know:
1. The fundamental differences between flows with negligible fluid density variation and compressible flows;
2. Apply the mass conservation and energy equations to viscous flows in pipes, calculate pressure drop, energy needs and available flux, and dimensioning simple pipes and ducts;
3. The fundamental principles of operation and the characteristic curves of centrifugal fans and pumps in view of selecting and analyze the operation of such equipment;
4. The principles of operation and the domains of use of the most common types of speed meters, flow meters and pressure transducers;
5. Understand the essential aspects of flows around immersed bodies and characterize the forces resulting from the interaction flow-body.

Working method

Presencial

Pre-requirements (prior knowledge) and co-requirements (common knowledge)

Mathematics, Mechanics I and II

Program

VISCOUS FLOW IN PIPES
General Characteristics of Pipe Flow. Laminar or Turbulent Flow. Entrance Region and Fully Developed Flow. Pressure and Shear Stress. Fully Developed Laminar Flow. From F = ma Applied Directly to a Fluid Element. From the Navier–Stokes Equations. From Dimensional Analysis. Energy Considerations. Fully Developed Turbulent Flow. Transition from Laminar to Turbulent Flow. Turbulent Shear Stress. Turbulent Velocity Profile. Turbulence Modeling. Chaos and Turbulence. Dimensional Analysis of Pipe Flow. Major Losses. Minor Losses. Noncircular Conduits. Pipe Flow Examples. Single Pipes. Multiple Pipe Systems. Pipe Flowrate Measurement. Pipe Flowrate Meters. Volume Flowmeters. Chapter Summary and Study Guide. References. Problems.

 

FLOW OVER IMMERSED BODIES.
General External Flow Characteristics. Lift and Drag Concepts. Characteristics of Flow Past an Object. Boundary Layer Characteristics. Boundary Layer Structure and Thickness on a Flat . Prandtl/Blasius Boundary Layer Solution. Momentum Integral Boundary Layer Equation for a F. Transition from Laminar to Turbulent Flow. Turbulent Boundary Layer Flow. Effects of Pressure Gradient. Momentum Integral Boundary Layer Equation with No. Drag. Friction Drag. Pressure Drag. Drag Coefficient Data and Examples. Lift. Surface Pressure Distribution. Circulation. hapter Summary and Study Guide. References. Problems.

 

OPEN CHANNEL FLOW
General Characteristics of Open-Channel Flow. Surface Waves. Wave Speed. Froude Number Effects. Energy Considerations. Energy Balance. Specific Energy. Uniform Flow. Uniform Flow Approximations. The Chezy and Manning Equations. Uniform Flow Examples. Gradually Varied Flow. Rapidly Varied Flow. The Hydraulic Jump. Sharp-Crested Weirs. Broad-Crested Weirs. Underflow (Sluice) Gates.

 

COMPRESSIBLE FLOW
Ideal Gas Thermodynamics. Stagnation Properties. Mach Number and Speed of Sound. Compressible Flow Regimes. Shock Waves. Normal Shock. entropic Flow. Steady Isentropic Flow of an Ideal Gas. Incompressible Flow and Bernoulli’s Equation. The Critical State. One-Dimensional Flow in a Variable Area Duct. General Considerations. Isentropic Flow of an Ideal Gas With Area Change. Operation of a Converging Nozzle. Operation of a Converging–Diverging Nozzle. Constant-Area Duct Flow With Friction. Preliminary Consideration: Comparison with Incompr. The Fanno Line. Adiabatic Frictional Flow (Fanno Flow) of an Ideal. Frictionless Flow in a Constant-Area Duct with Hea. The Rayleigh Line. Frictionless Flow of an Ideal Gas with Heating or . Rayleigh Lines, Fanno Lines, and Normal Shocks. Analogy between Compressible and Open-Channel Flow. Two-Dimensional Supersonic Flow.

 

TURBOMACHINES
Introduction. Basic Energy Considerations. Angular Momentum Considerations. The Centrifugal Pump. Theoretical Considerations. Pump Performance Characteristics. Net Positive Suction Head (NPSH). System Characteristics, Pump-System Matching, and . Dimensionless Parameters and Similarity Laws. Special Pump Scaling Laws. Specific Speed. Suction Specific Speed. Axial-Flow and Mixed-Flow Pumps. Fans. Turbines. Impulse Turbines. Reaction Turbines. Compressible Flow Turbomachines. Compressors. Compressible Flow Turbines.

INTRODUCTION TO COMPUTATIONAL FLUID DDYNAMICS (CFD)

Introduction. What is CFD?. A Very Simple Example. Discretization. The Computational Grid. Boundary Conditions. Turbulence Models. Solving the equations. Some Unexpected Complications. Verification and Validation. Application of CFD. Advantages of CFD.

Mandatory literature

Philip M. Gerhart, John I. Hochstein, Andrew L. Gerhart; Munson, Young and Okiishi's Fundamentals of Fluid Mechanics, 9th Edition, Wiley, 2021. ISBN: 978-1-119-59811-4

Complementary Bibliography

Russell C. Hibbeler; Fluid Mechanics (in SI Units), 2nd GLOBAL Edition, 2020. ISBN: 9781292247304

Teaching methods and learning activities

The course is organized in three classes per week, each one with a duration of 1.5 hour. Two sessions are theoretical and the other one a teoretical-pratical session.

There will be three 2 hour lab session.

Participation in the 3 laboratory sessions (each lasting 2 hours) is compulsory for first-time students.

Students who have held laboratory sessions in the 2021-2022 academic year may choose not to attend these sessions, maintaining the previous year's classification.

Software

Matlab

keywords

Physical sciences > Physics > Classical mechanics > Fluid dynamics
Technological sciences > Engineering > Mechanical engineering > Propulsion systems engineering
Technological sciences

Evaluation Type

Distributed evaluation with final exam

Assessment Components

Designation	Weight (%)
Exame	60,00
Teste	30,00
Trabalho laboratorial	10,00
Total:	100,00

Amount of time allocated to each course unit

Designation	Time (hours)
Estudo autónomo	101,00
Frequência das aulas	59,00
Trabalho laboratorial	6,00
Total:	166,00

Eligibility for exams

Attendance of, at least, 70% of theoretical-practical and lab sessions.

Participation in the 3 laboratory sessions (each lasting 2 hours) is compulsory for first-time students.

Students who have held laboratory sessions in the 2021-2022 academic year may choose not to attend these sessions, maintaining the previous year's classification.

Calculation formula of final grade

Two theoretical exams, in Moodle platform, at the end of the semester. Exam without consultation, 30 minutes in duration.
Written practical examination at the examinations season. Limited consultation (two A4 pages), 90minutes in duration. A minimum grade of 7/20 is required as a classification of the theoretical exam (Moodle) to have access to this practical exam.
The overall grade will be obtained weighting by 30% the average grade in the theoretical exam (Moodle) and by 60% the practical test.


All students must participate in the laboratory sessions. 

The improvement/final examination includes, as a whole, both theoretical and practical components. The weight of theoretical and practical components will be the same as in the regular examination.

Final grade can be adjusted plus or minus 1/20, in function of assiduity, participation in the classes, etc..

Students with marks above 16/20, may have an oral examination.

Examinations or Special Assignments

Not planned.

Internship work/project

Not applicable.

Special assessment (TE, DA, ...)

According to FEUP regulations, with rules similar to the ones of the improvement/final examination.

Classification improvement

According to FEUP regulations, simultaneously with improvement/final examination, with the same rules.

Observations

Language of instruction: Portuguese