Final Fluid dynamics Flashcards
(17 cards)
What are the two types of fluid forces?
Buoyant and Dynamic
Buoyant force
- always acts vertically, upward on an object immersed in a fluid
- its equal to the weight of the volume of the fluid displaced by the object
(Bouncy ball moves up and down)
Dynamic force
proportional to the density of the fluid, the surface area of the object immersed in the fluid, and the square of the relative velocity of the object of the fluid
What is Dynamic fluid broken into?
Lift force and Drag force
Drag force
resistance to movement
- acts in opposition to relative motion of the object with respect to the fluid
What is drag force broken into?
surface drag and form drag
Surface drag
Friction occurs between the surface and the molecules
The coefficient of surface drag is influenced by?
1- roughness of the surface - equipment and clothing of athlete are smooth to reduce surface drag
2. Viscosity- measure of internal friction between the layers of molecules
Form Drag
the molecule will follow the curvature of the objects surface area as it moves past
- Laminar flow and Turbulent flow
What is the form drag coefficient
1- shape of the object
2. surface texture
Lift force
acts perpendicular to motion
Bernoullis principle
As speed increases the pressure decreases
As pressure decreases then lift increases
Manus Effect
Lift force causes spin
Center of pressure
theoretical point of application of the force to the object
How do you determine if an object floats?
the volume of the object immersed and the weight of the object
What happens when the material weighs more than the volume of water?
buoyancy force will act upon it and it will accelerate downwards
Specific gravity
ratio of the weight of the object to the weight and an equal volume of water
