Question

What is the Reynolds number for blood leaving the heart through the aorta if the diameter of the aorta is 2.15 cm and the blood has a dynamic viscosity of 2.70 × 10-3 Pa·s, a density of 1050 kg/m3, and travels at a mean fluid velocity of 15.9 cm/s?
The blood flow through the aorta in the given scenario is:

a) turbulen

b) laminar

c) transitioning between laminar and turbulen.

Answer 1

Answer:

b. laminar flow

the reynold number is 1329.26

Explanation:

Re = (V x D x ρ)/ η

where,

V = mean velocity = 15.9 cm/s = 0.159m/s

D = vessel diameter = 2.15cm = 0.0215m

ρ = blood density = 1050 kg/m3 = 0.00105 kg/cm3

η = dynamic viscousity= 2.70 × 10-3 Pa·s = 2.70 × 10-3 kg/m-s

applying the formular to calculate for reynolds number, Re =

Re = (V x D x ρ)/ η

   =(0.159 x 0.0215 x 1050) / 2.70 × 10-3

   =3.589/0.0027 = 1329.26

the Reynolds number for the blood leaving the heart through the aorta if the diameter of the aorta is 2.15 cm and the blood has a dynamic viscosity of 2.70 × 10-3 Pa·s, a density of 1050 kg/m3, and travels at a mean fluid velocity of 15.9 cm/s is 1329.26

which flow through the aorta in a Laminar flow

Note that

a) turbulen= Re  >4000

b) laminar= Re  <2300

c) transitioning between laminar and turbulen= Re between 2100 and 4000