Swimming Mechanics: Reynolds Number Flashcards
1
Q
What does inertia do?
A
- allows for continued fwd motion between swimming strokes
2
Q
What needs to happen for the fish to move fwd?
A
- inertial forces (momentum) must be greater than viscous forces (drag)
3
Q
What does Reynolds number do?
A
- predicts ratio of inertial vs. viscous forces
4
Q
Fast swimmers have a ______ Re
A
high
5
Q
Velocity ____ at small size
A
dominates
6
Q
Bigger animals move ____. This is due to ____.
A
- faster
- inertial force
7
Q
What is reynolds equation?
A
Re = body length * Speed * density of water / Viscosity of water
8
Q
The ratio of reynolds number is what unit?
A
unitless because they cross eachother out
9
Q
What is reynolds number used for?
A
to predict relative ease of locomotion in a fluid medium
10
Q
What is constant in reynolds equation?
A
- density and viscosity
11
Q
What do you look for in reynolds number?
A
- Re of body length (size) and speed
12
Q
Re is proportional to what?
A
- inertial forces
13
Q
What is Re inversely proportional to?
A
- viscous forces (DRAG)
14
Q
What happens if Re>1?
A
- fish moves forward
15
Q
Small fish have ____ drag. What does this mean?
A
- higher drag = slower moving
