LE 2: Flow Past Immersed Objects

Question 1

Flow of small particles through gas/liquid (low viscosity)

Answer 1

creeping flow

Question 2

if there’s a high Nre, what happens?

Answer 2

a. wake shrinks
b. stagnation point
c. separation point moves smaller

Question 3

in this type of drag, there is a stagnation

Answer 3

skin/wall drag

Question 4

it is defined as the ratio of drag force per unit area to the product
density times velocity head

Answer 4

friction factor

Question 5

what is the assumption in the flow in backed beds

Answer 5

packing is uniform

Question 6

it is the additional frictional losses due to change in the direction of the fluid flow

Answer 6

form drag

Question 7

what are the common fluids used in immersed solids flow?

Answer 7

a. water
b. air

Question 8

it is the flow of the fluid

Answer 8

streamlines

Question 9

this is used for low reynold’s number

Answer 9

stoke’s law

Question 10

this is a very short stop in a skin/wall drag

Answer 10

stagnation

Question 11

Larger particles through gas/liquid (high viscosity)

Answer 11

creeping flow

Question 12

valid only if the Reynold’s number is

Answer 12

stoke’s law

Question 13

this type of drag already has an immersed object

Answer 13

skin/wall drag

Question 14

these are viscous forces since inertial forces are negligible

Answer 14

wall shear (drag)

Question 15

at this point, fluid velocity will be zero and boundary layer growth begins at this point and continues over a surface until it separates

Answer 15

stagnation point

Question 16

other term for packed beds?

Answer 16

packed columns

Question 17

it is the force exerted by the fluid on the solid direction flow

Answer 17

skin/wall drag

Question 18

this is used if less than unity

Answer 18

stoke’s law

Question 19

it is the force in the direction of the flow exerted by the fluid

Answer 19

drag force

Question 20

in stoke’s law, this will be coming from the viscosity

Answer 20

wall shear (drag)

Question 21

this is the resistance

Answer 21

creeping flow

Question 22

at stagnation point, this will be zero

Answer 22

fluid velocity

Question 23

this is important between the fluid and solid in immersed solids

Answer 23

relative velocity

Question 24

this forms to the right of the object will the fluid is flowing

Answer 24

turbulence

Question 25

what do you call the flow where the fluid regain its flow

Answer 25

creeping flow

Question 26

3 points of separation

Answer 26

a. shape or geometry of the particle b. reynold's number (characteristic of the flow) c. others

Question 27

At ______________ at which the law is valid, the sphere moves through the fluid by deforming it.

Answer 27

low velocities

Question 28

this has no wake shrinks and the flow of the fluid goes back to the object

Answer 28

critical reynold's number