Flashcards in Bruce's Fluid Dynamics Final Prep Deck (52)

Loading flashcards...

1

## Pressure definition ?

### the force per unit area applied in a direction perpendicular to the surface of an object

2

## Hydrostatic pressure

### (AKA: Stagnation Pressure) The pressure at any given point of a non-moving ﬂuid

3

## what do we measure with our manometers ?

### Static Pressure

4

## Hydrostatic Pressure - Static Pressure =

### Dynamic Pressure

5

## ‘Where the velocity of the ﬂuid is high

###
the (static) pressure is low’

6

## Static Pressure + dynamic pressure =

### Total Pressure

7

## Bernoulli's Priciple =

###
P+1/2pv^2 = Po

P=static pressure

p=density of the fluid

v=flow velocity

Po=total pressure

8

## Velocity is directly related to ?

###
=Flow

and inversely related to cross sectional area.

9

## Boundary layers are slower in ?

### the edge

10

## Boundary layers are faster in ?

### the middle

11

## 3 types of ﬂuid ﬂow in pipes ?

###
• laminar

• turbulent

• transient

12

## Laminar Flow =

### happens when dealing with small pipes and low ﬂow velocities

13

## Turbulent Flow =

###
- vortices, eddies and wakes make the ﬂow unpredictable

- happens in general at high ﬂow rates and with larger pipes

14

## Transitional Flow =

### mixture of laminar and turbulent ﬂow, with turbulence in the center of the pipe, and laminar ﬂow near the edges

15

## Transient flow range =

### 2300 < 4000

16

## Laminar Flow range =

### RE < 2300

17

## Turbulent flow range =

### RE > 4000

18

## Reynolds number (Formula) =

###
Re =

(velocity)(radius)(density)

_____________________

Viscocity

19

## Poiseuille's law on blood circulation in the body is dependent on what?

### Laminar flow

20

## In turbulent ﬂow the ﬂow rate is proportional to the

### square root of the pressure gradient

21

## atheroma = turbulent flow

### is an accumulation of degenerative material in the tunica intima (inner layer) of artery walls.

22

## Rapid changes in vessel diameter may lead to what?

### Turbulent flow

23

## As the blood leaves the arterial cannula, it is ____ flow?

### Turbulent

24

## Poiseuille’s Law:

###
Delta P =8u L Q / pi r^4

Delta P = pressure loss

L = length of pipe

u = dynamic viscosity

Q = volumetric flow rate

r = radius

d = diameter

pi = mathematical constant Pi

25

## As length increases. .

###
-Resistance Increases

-Flow decreases

for a given pressure

26

## As radius increases. .

###
-Resistance decreases

-Flow increases

for a given pressure

27

##
which oxygenator circuit has a lower resistance ?

series or parallel?

### parallel

28

## Two variable that we manipulate that alter blood viscosity:

###
1-Temperature

2-Hematocrit

29

## Viscosity definition ?

### a measure of the resistance of a ﬂuid which is being deformed by either shear or tensile stress

30