Forms of energy and Flow

Question 1

Energy of motion

Answer 1

Kinetic

Question 2

Kinetic energy is proportional to ____ and ____ of velocity.

Answer 2

It is proportional to mass and square of velocity.

Question 3

Stored energy

Answer 3

Potential

Question 4

Potential energy translates to what?

Answer 4

Pressure against walls: BP

Question 5

What type of energy constitutes by far the greatest proportion of the overall energy?

Answer 5

Potential energy

Question 6

What are the two components of potential energy?

Answer 6

1. Hydrostatic pressure

2. Gravitational potential energy

Question 7

Hydrostatic pressure is gravity acting on what?

Answer 7

Gravity acting on a column of fluid

Question 8

Gravitational potential energy is proportional to what?

Answer 8

It is proportional to the height of a column of fluid

Question 9

Hydrostatic pressure is ____ at the ____ point, where as gravitational potential energy is ____ at the ____ point in a column of fluid.

Answer 9

Hydrostatic pressure is highest at the lowest point. Gravitational potential energy is highest at the highest point.

Question 10

Basic flow equation:

Answer 10

Q= ΔP

R

Question 11

Another flow equation:

Answer 11

Q= v x CSA

Question 12

Resistance equation:

Answer 12

R= 8Ln

πr4

Question 13

If you increase the length or viscosity it causes the resistance to ____.

Answer 13

Increase

Question 14

If you increase the radius, the resistance ____ GREATLY.

Answer 14

Decreases

Question 15

If you double the radius, you reduce the resistance to what?

Answer 15

1/16

Question 16

Poiseuille’s law:

Answer 16

Q= ΔPπr4

8Ln

Question 17

Which component of Poiseuilles law has the most profound effect on flow?

Answer 17

Radius

Question 18

What is laminar flow?

Answer 18

Orderly flow moving in concentric layers.

Question 19

The layer next to the wall of a vessel is theoretically ____.

Answer 19

Motionless

Question 20

Where is the fastest velocity?

Answer 20

Center stream

Question 21

Center stream velocity is __x the mean velocity.

Answer 21

2x

Question 22

What flow profile has the same velocities across the lumen?

Answer 22

Plug

Question 23

In which vessels and during what part of the cardiac cycle does Plug profile occur?

Answer 23

It occurs:

• at the initial systolic push
• at systole in large vessels >3mm
• at entrances to stenosis
• at entrances to branching

Question 24

In which vessels and during what part of the cardiac cycle does Parabolic profile occur?

Answer 24

It occurs:

• at late systole
• throughout cardiac cycle in small vessels < 3mm
• in diastole in large vessels >3mm

Question 25

What characteristics show parabolic and plug profiles on spectral display?

Answer 25

Narrow range of velocities at the systolic upstroke represents plug flow, and a wider range of velocities during diastole represents parabolic flow.

Question 26

What does the systolic window on spectral display represent?

Answer 26

Orderly laminar flow moving at a narrow range of velocities.

Question 27

What type of flow is it when the systolic window is filled in?

Answer 27

Turbulence

Question 28

What is the flow pattern in higher-resistance peripheral arteries?

Answer 28

Multi-phasic: having a forward, reverse, and second forward component.

Question 29

Lower resistance equals ____ diastolic flow.

Answer 29

more diastolic flow

Question 30

Higher resistance equals ____ diastolic flow.

Answer 30

less diastolic flow

Question 31

2 characteristics of flow at bifurcations

Answer 31

1. Flow disturbance occurs here normally (common site for plaque) 2. Boundary layer of separation

Question 32

In boundary layer of separation the shear forces are ____ at the flow divider, and ____ on wall away from the flow divider.

Answer 32

Shear forces are higher at the flow divider, and lower on wall away from the flow divider.

Question 33

Faster flow is at the ____ contour.

Answer 33

Outer

Question 34

Slower flow is at the ____ contour.

Answer 34

Inner