1. Introduction to Fluid Mechanics
Chapter 3
Fluid Statics

2. Main Topics The Basic Equations of Fluid Statics
Pressure Variation in a Static Fluid
Hydrostatic Force on Submerged Surfaces
Buoyancy

3. The Basic Equations of Fluid Statics
Body Force

4. The Basic Equations of Fluid Statics
Surface Force

5. The Basic Equations of Fluid Statics
Surface Force

6. The Basic Equations of Fluid Statics
Surface Force

7. The Basic Equations of Fluid Statics
Total Force

8. The Basic Equations of Fluid Statics
Newton’s Second Law

9. The Basic Equations of Fluid Statics
Pressure-Height Relation

10. Pressure Variation in a Static Fluid
Incompressible Fluid: Manometers

11. Pressure Variation in a Static Fluid
Compressible Fluid: Ideal Gas
Need additional information, e.g., T(z) for atmosphere

12. Hydrostatic Force on Submerged Surfaces
Plane Submerged Surface

13. Hydrostatic Force on Submerged Surfaces
Plane Submerged Surface
We can find FR, and y´ and x´,
by integrating, or …

14. Hydrostatic Force on Submerged Surfaces
Plane Submerged Surface
Algebraic Equations – Total Pressure Force

15. Hydrostatic Force on Submerged Surfaces
Plane Submerged Surface
Algebraic Equations – Net Pressure Force

16. Hydrostatic Force on Submerged Surfaces
Curved Submerged Surface

17. Hydrostatic Force on Submerged Surfaces
Curved Submerged Surface
Horizontal Force = Equivalent Vertical Plane Force
Vertical Force = Weight of Fluid Directly Above (+ Free Surface Pressure Force)

18. Buoyancy

19. For example, for a hot air balloon (Example 3.8):
Buoyancy
For example, for a hot air balloon (Example 3.8):