Ch.5 Wkst 1&2

Question 1

Flow

Answer 1

to move in a stream continually changing position and possibly direction.

Question 2

Fluids

Answer 2

a material that flows and conforms to the shape of its container (gas or liquid).

Question 3

Flow Resistance

Answer 3

pressure difference divided by volume flow rate for steady flow.

R(g/cm⁴-s)=8xL(cm)x Π(poise) / π x[r⁴(cm⁴)]

Question 4

Volumetric Flow Rate

Answer 4

volume of fluid passing a point per unit of time (per second or minute).

Q(mL/s)=^P(dyne/cm²) / R(poise)

or Poiseuille’s Equation:

Q(mL/s)= ^P(dyne/cm²)xπxd⁴(cm⁴) / 128xL(cm)xΠ(poise)

Question 5

Pressure Gradient (slope)

Answer 5

pressure difference divided by distance between the two pressure locations.

Question 6

Viscosity

Answer 6

resistance of fluid to flow.

R(poise) =^P(dyne/cm²) / Q(mL/s)

Question 7

Plug flow

Answer 7

flow with all fluid portions traveling with the same flow speed and direction.

Question 8

Laminar flow

Answer 8

flow in which fluid layers slide over each other in a smooth, orderly manner, with no mixing between layers.

Question 9

Parabolic flow

Answer 9

laminar flow with a profile in the shape of a parabola.

Question 10

Disturbed flow

Answer 10

flow that cannot be described by straight parallel streamlines.

Question 11

Turbulent flow

Answer 11

random, chaotic, multidirectional flow of a fluid with mixing between layers; flow that is not laminar.

Question 12

Pulsatile flow

Answer 12

flow that accelerates and decelerates with each cardiac cycle.

Question 13

Continuity Rule

Answer 13

blood is neither created nor destroyed as it flows through a vessel.

Question 14

Bernoulli Effect

Answer 14

pressure reduction in a region of high-flow speed. Pressure Drop (where V2=flow speed at stenosis): △P=4(V2)2