CE 204 FLUID MECHANICS - Okan Üniversitesi · PDF fileCE 204 FLUID MECHANICS Onur AKAY...
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Chapter 3 Fluid Statics Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib. CE 204 FLUID MECHANICS Onur AKAY Assistant Professor Onur Akay, Ph.D. CE 204 Fluid Mechanics 1 Okan University Department of Civil Engineering Akfırat Campus 34959 Tuzla-Istanbul/TURKEY Phone: +90-216-677-1630 ext.1974 Fax: +90-216-677-1486 E-mail: [email protected]
Transcript of CE 204 FLUID MECHANICS - Okan Üniversitesi · PDF fileCE 204 FLUID MECHANICS Onur AKAY...
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
CE 204
FLUID MECHANICS
Onur AKAY
Assistant Professor
Onur Akay, Ph.D. CE 204 Fluid Mechanics 1
Assistant Professor
Okan University
Department of Civil Engineering
Akfırat Campus
34959 Tuzla-Istanbul/TURKEY
Phone: +90-216-677-1630 ext.1974
Fax: +90-216-677-1486
E-mail: [email protected]
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Forces on Plane Surfaces (Review):
A plane surface or panel is a flat surface of arbitrary shape.
A description of the pressure at all points along a surface is called pressure distribution.
Onur Akay, Ph.D. CE 204 Fluid Mechanics 2
For a uniform pressure distribution, the CP is located at the centroid of area of the panel.
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Forces on Plane Surfaces (Review):
Onur Akay, Ph.D. CE 204 Fluid Mechanics 3
For a hydrostatic pressure distribution, the CP is located below the centroid of area.
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Magnitude of Resultant Hydrostatic Force (Review):
Onur Akay, Ph.D. CE 204 Fluid Mechanics 4
Hydrostatic force = (Pressure at the centroid of area) x (Panel area)
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Line of Action of the Resultant Force (Review):
Area
Moment of
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Moment of
Inertia
- Applies only to a single fluid of constant density
- Pressure at liquid surface p=0 gage
- Gives only the vertical location of the CP
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Forces on Curved Surfaces:
AC: Simulate as vertical gate
CB: Simulate as horizontal gate
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Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Onur Akay, Ph.D. CE 204 Fluid Mechanics 7
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Forces on Curved Surfaces:
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Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Problem 3.76:
Determine the hydrostatic force acting on the radial gate if the gate is 15 m long (normal to
the page). Show the line of action of the hydrostatic force acting on the gate.
Onur Akay, Ph.D. CE 204 Fluid Mechanics 9
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Buoyancy:
The upward force that is produced on a body that is totally or partially submerged in a fluid.
The Buoyant Force Equation:
Onur Akay, Ph.D. CE 204 Fluid Mechanics 10
Displaced
volume Archimedes´ principle
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Onur Akay, Ph.D. CE 204 Fluid Mechanics 11
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Stability of Immersed and Floating Bodies:
Stability: Determines whether an object will tip over or remain in an upright position when
placed in a liquid.
Immersed Bodies: Center of buoyancy (C) is at the centroid of the displaced volume.
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Stable
(righting couple)
Neutral Unstable
(overturning couple)
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Floating Bodies: Center of Buoyancy (C) may take different positions.
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Metacenter, M: Point of intersection of the lines of action of FB.
Metacentric Height, GM: Distance between G and M.
If M is above G, the ship is stable (GM+)
MOVIE
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Floating Bodies:
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Righting or Overturning Moment:
GM (+): STABLE
GM (-): UNSTABLE
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
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Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Relative Equilibrium:
If a fluid mass is subjected to an external acceleration , an additional force will be
introduced (No relative motion of the liquid particles, no shear stress).
Liquid Subject to Horizontal & Vertical Acceleration:
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Fluid Mass Under Constant Linear Acceleration
The acceleration affects depth but does not change the relationship:
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
Fluid Mass Rotating at Constant Angular Velocity :
Constant angular velocity: w (rad/s)
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Rotating Fluid Mass
Chapter 3 Fluid Statics
Forces on Curved Surfaces, Buoyancy, Stability of Immersed and Floating Bodies, Relative Equilib.
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