# Fluid Mechanics

## Course Description:

Knowledge of the fundamental laws of fluid mechanics and ability to solve problems regarding stagnant and fluids in motion. Hydrostatic forces on flat and curved surfaces and submerged bodies. Computation of flow parameters of ideal and real fluids. Computation of the flow using control volume analysis. Laminar flow, introduction to turbulent flow and boundary layer. Velocity distributions and friction coefficient.

### Prerequisite Knowledge

Mechanics of deformable bodies, Calculus of several variables, Differential equations

### Course Units

# Title Description Hours
1 Introduction Fluid properties. 1Χ4=4
2 Hydrostatics Hydrostatics equation, pressure distribution in homogeneous and density-stratified fluids, manometers, pressure forces on flat and curved surfaces, Archimedes principle, buoyancy force on submerged bodies. 2Χ4=8
3 Kinematics Eulerian and Lagrangian flow description. Streamlines, streaklines, pathlines and timelines. Deformation of fluid elements, vorticity and circulation. 1Χ4=4
4 Fundamental laws of fluid mechanics Differential analysis of the flow. Mass, momentum and energy conservation principles, continuity and Navier Stokes equations. 1Χ4=4
5 Control volume analysis Reynolds transport theorem,continuity, momentum and energy equations. Energy and hydraulic grade lines, hydraulic machinery, pumps and turbines. 2Χ4=8
6 Ideal fluid and applications Euler and Bernoulli equations, irrotational flow, potential and stream function, Laplace equation, Pitot tube.Flow separation and cavitation. Flow discharge through orifices, trajectory of free jets, flow over weirs and under sluice gates. 2Χ4=8
7 Viscous fluids Reynolds number, laminar and turbulent flow. Lift and drag forces on submerged bodies in a moving fluid. 1Χ4=4
8 Laminar flow Couette and Poiseuille flow. 1Χ4=4
9 Turbulent flow in pipes, boundary layer, velocity distribution, energy loss Laminar and turbulent boundary layer, displacement and momentum thickness, boundary shear stress. Velocity distributions in turbulent pipe flow. Darcy-Weisbach equation, friction energy losses. Friction coefficient in turbulent and laminar flow, Colebrook-White equation, Moody diagram. 2Χ4=8

### Learning Objectives

Upon the successful completion of the course the student will be able to:

o Calculate pressure forces on flat and curved submerged surfaces o Calculate flow velocity and pressure distribution using control volume analysis in open and in closed (confined) flow fields, as well as the dynamic loads on structures that contain or are submerged in the moving fluid o Calculate flow rate through orifices, over weirs and under sluice gates o Calculate lift and drag forces on submerged bodies in a moving fluid o Calculate the velocity and shear stress distribution in laminar flow fields o Calculate friction energy loss and draw the energy (EGL) and hydraulic grade lines (HGL) in closed systems

### Teaching Methods

 Teaching methods Lectures. Power point lectures, fluid mechanics films from laboratory or field experiments and natural flows The solutions of 7-8 problem sets assigned, to be returned by the students.

### Student Assessment

• Final written exam: 70%
• Mid-term exam: 15%
• Problems - Applications: 15%

### Textbooks - Bibliography

1. Νουτσόπουλος, Γ. Χριστοδούλου Γ. Μαθήματα Μηχανικής των Ρευστών, Εκδόσεις Φούντα
2. Λιακόπουλος Α. Μηχανική Ρευστών, Εκδόσεις Τζιόλα.
3. Elger, DF, Williams, BC, Crowe, CT and Robertson, JA, 2016. Μηχανική ρευστών για μηχανικούς, 10η Έκδοση, Εκδόσεις Τζιόλα.
4. Gerhart, PM, Gerhart, AL, Hochstein, JI, 2017. Munson, Young και Okiishi’s Μηχανική ρευστών, 8η Έκδοση, Εκδόσεις Τζιόλα.

## Lecture Time - Place:

• Tuesday, 12:45 – 14:30,
Rooms:
• Ζ. Κτ. 1 Πολ., Αιθ. 1
• Ζ. Κτ. 1 Πολ., Αιθ. 7
• Friday, 12:45 – 14:30,
Rooms:
• Αιθ. 17
• Ζ. Κτ. 1 Πολ., Αιθ. 12

© 2017 School of Civil Engineering, ΕΜΠ