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A soft drink with the properties of 10 oC water is sucked through a 4.1-mm-diameter, 0.25-m-long straw at a rate of 4.1 cm3/s.

(a) Is the flow at the outlet of the straw laminar?
(b) Is it fully developed? To explain calculate
(c) the Reynolds number and
(d) the entrance length.

User Vasko
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1 Answer

6 votes

Answer:

1. it is laminar flow

2. it is not fully developed

3.Re=63.156

4. entrance length is the entrance diameter which is 4.1-mm-

Step-by-step explanation:

A soft drink with the properties of 10 oC water is sucked through a 4.1-mm-diameter, 0.25-m-long straw at a rate of 4.1 cm3/s.

(a) Is the flow at the outlet of the straw laminar?

(b) Is it fully developed? To explain calculate

(c) the Reynolds number and

(d) the entrance length

note te following

For&pipe&flow:&

Re&<&2100 laminar&flow&

Re&>&4000 turbulent&flow&

kinematic viscosity of water at 10 oCis 1.267E-6m^2/S

Re=vl/k.viscosity

v=q/A

q=4.1 cm3/s=4.1*10^-6m3/s

A=3.142*0.0041/4

A=0.00322m2

v=0.000318m/s

l= 0.25-m

RE=0.000318m/s*0.25/( 1.267E-6m^2/S)

Re=63.156

since re<2100 , it is laminar flow

2. it is not fully developed

3.Re=63.156

4. entrance length is the entrance diameter wic is 4.1-mm-

User Joasa
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