Exam 15: Fluid Dynamics and Aerodynamics

A square smooth conduit, 80 cm on a side, circulates 35 $35 ^ { \circ } \mathrm { C }$ C air in a large building. The pressure drop over a 50-m length of the horizontal conduit is not to exceed 800 Pa. Assume an average Pressure in the conduit of 120 kPa. The maximum flow rate in the conduit is nearest:

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(Multiple Choice)

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Question 1

Correct Answer:

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B

If the average velocity in the pipe of Number 2 is 5 m/s, the energy grade line would increase suddenly at the pump a distance nearest:

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Question 2

Correct Answer:

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D

An aircraft flies at an altitude of 20,000 m. With what speed would it fly if M = 1?

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(Multiple Choice)

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Question 3

Correct Answer:

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C

A smooth 10-cm-diameter sphere weighs 6 N. If it is dropped in 5 $5 ^ { \circ } \mathrm { C }$ C water, its terminal velocity will be nearest:

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Question 4

$\text {If the straight-line approximation u = U _ { \infty } y / \delta to the velocity profile is used, the boundary-}$ $\text {layer thickness for a zero-pressure gradient flow on a flat plate would be approximated to be:}$

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Question 5

$\text {In the region near the wall where \overline { u ^ { \prime } v ^ { \prime } } is constant, if $\bar { u } ( y ) = c _ { 1 } \ln y + c _ { 2 }$ (see Example $7.8$ ), the }$ $\text {eddy viscosity \eta is proportional to:}$

(Multiple Choice)

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Question 6

The drag on a blunt object is due primarily to:

(Multiple Choice)

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Question 7

A tall cell-phone tower is 12 cm in diameter over much of the height. A wind blows at 25 m/s. The frequency of the vortices being shed from the tower is nearest:

(Multiple Choice)

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Question 8

The shear velocity in the 60-mm-diameter horizontal water pipe of Problem 2 is nearest:

(Multiple Choice)

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Question 9

One liter of $20 ^ { \circ } \mathrm { C }$ C water is collected from a 60-cm-long, 4-mm-diameter tube over a time span of 4 minutes. The length of the entrance region is nearest:

(Multiple Choice)

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Question 10

$\text {If an irrotational vortex approximates the air flow in a tornado, the highest possible velocity,}$ $\text {assuming an incompressible flow with p _ { \text {atm } } = 100 \mathrm { kPa }, is nearest:}$

(Multiple Choice)

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Question 11

The free-stream flow outside a boundary layer is:

(Multiple Choice)

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Question 12

The horsepower required to rotate the shaft of Problem 2, if SAE-30 oil at 40 $40 ^ { \circ } \mathrm { C }$ ills the gap, is nearest:

(Multiple Choice)

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Question 13

A farmer is using a tank of 20 $20 ^ { \circ } \mathrm { C }$ C nitrogen pressurized to 540 kPa absolute. It exits the tank out a hose. The hose snaps and the farmer is hit with the expanding nitrogen. Air is primarily Nitrogen so assuming it is air flowing with no losses, the temperature of the exiting nitrogen is Nearest:

(Multiple Choice)

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Question 14

Water at 20 $20 ^ { \circ } \mathrm { C }$ C flows between 80-cm-wide horizontal parallel plates 12 mm apart such that a pressure drop of 100 Pa occurs over a distance of 2 m. If the top plate is moving at 1.8 m/s inThe direction of the flow, the flow rate is nearest:

(Multiple Choice)

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Question 15

$\text {Water at 20 ^ { \circ } \mathrm { C } is transported in a 10 -cm-diameter cast iron horizontal pipe at a flow rate of}$ $\text { 0.02 \mathrm {~m} ^ { 3 } / \mathrm { s }. The pressure drop over $100 \mathrm {~m}$ of the pipe is nearest:}$

(Multiple Choice)

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Question 16

$\text {It is desired to transport 4 \mathrm {~m} ^ { 3 } / \mathrm { s } of water through a rectangular finished concrete canal that can}$ $\text { be at most 2 \mathrm {~m} wide. The slope of the land through which it passes is $0.0004$. What depth of}$ $\text {water should be expected?}$

(Multiple Choice)

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Question 17

In which one of the following flows must compressibility be considered?

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Question 18

$\text {A large dirigible measures 18 \mathrm {~m} in diameter and is $100 \mathrm {~m}$ long. The thin boundary layer can}$ $\text {be assumed to be developing on a flat plate with thickness at the leading edge. The drag}$ $\text {contributed by the shear stress due to the boundary layer for a dirigible speed of 10 \mathrm {~m} / \mathrm { s } is}$ $\text { approximately:}$

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Question 19

$\text {If the velocity profile in a boundary layer was approximated by the linear distribution}$ $\text {u = A y + B, the boundary condition(s) that the profile would be required to satisfy is (are):}$

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Question 20

If the average velocity in the pipe of Number 2 is 5 m/s, the energy grade line would increase suddenly at the pump a distance nearest:

An aircraft flies at an altitude of 20,000 m. With what speed would it fly if M = 1?

A smooth 10-cm-diameter sphere weighs 6 N. If it is dropped in 5 $5 ^ { \circ } \mathrm { C }$ C water, its terminal velocity will be nearest:

$\text {If the straight-line approximation u = U _ { \infty } y / \delta to the velocity profile is used, the boundary-}$ $\text {layer thickness for a zero-pressure gradient flow on a flat plate would be approximated to be:}$

$\text {In the region near the wall where \overline { u ^ { \prime } v ^ { \prime } } is constant, if \(\bar { u } ( y ) = c _ { 1 } \ln y + c _ { 2 }\) (see Example \(7.8\) ), the }$ $\text {eddy viscosity \eta is proportional to:}$

The drag on a blunt object is due primarily to:

A tall cell-phone tower is 12 cm in diameter over much of the height. A wind blows at 25 m/s. The frequency of the vortices being shed from the tower is nearest:

The shear velocity in the 60-mm-diameter horizontal water pipe of Problem 2 is nearest:

One liter of $20 ^ { \circ } \mathrm { C }$ C water is collected from a 60-cm-long, 4-mm-diameter tube over a time span of 4 minutes. The length of the entrance region is nearest:

$\text {If an irrotational vortex approximates the air flow in a tornado, the highest possible velocity,}$ $\text {assuming an incompressible flow with p _ { \text {atm } } = 100 \mathrm { kPa }, is nearest:}$

The free-stream flow outside a boundary layer is:

The horsepower required to rotate the shaft of Problem 2, if SAE-30 oil at 40 $40 ^ { \circ } \mathrm { C }$ ills the gap, is nearest:

Water at 20 $20 ^ { \circ } \mathrm { C }$ C flows between 80-cm-wide horizontal parallel plates 12 mm apart such that a pressure drop of 100 Pa occurs over a distance of 2 m. If the top plate is moving at 1.8 m/s inThe direction of the flow, the flow rate is nearest:

$\text {Water at 20 ^ { \circ } \mathrm { C } is transported in a 10 -cm-diameter cast iron horizontal pipe at a flow rate of}$ $\text { 0.02 \mathrm {~m} ^ { 3 } / \mathrm { s }. The pressure drop over \(100 \mathrm {~m}\) of the pipe is nearest:}$

$\text {It is desired to transport 4 \mathrm {~m} ^ { 3 } / \mathrm { s } of water through a rectangular finished concrete canal that can}$ $\text { be at most 2 \mathrm {~m} wide. The slope of the land through which it passes is \(0.0004\). What depth of}$ $\text {water should be expected?}$

In which one of the following flows must compressibility be considered?

$\text {If the velocity profile in a boundary layer was approximated by the linear distribution}$ $\text {u = A y + B, the boundary condition(s) that the profile would be required to satisfy is (are):}$

Basic Considerations

Fluid Statics

Introduction to Fluids in Motion

The Integral Forms of the Fundamental Laws

The Differential Forms of the Fundamental Laws

Dimensional Analysis and Similitude

Internal Flows

External Flows

Compressible Flow

Flow in Open Channels

Flows in Piping Systems

Turbomachinery

Measurements in Fluid Mechanics

Computational Fluid Dynamics

Filters

Exam 15: Fluid Dynamics and Aerodynamics

If the average velocity in the pipe of Number 2 is 5 m/s, the energy grade line would increase suddenly at the pump a distance nearest:

An aircraft flies at an altitude of 20,000 m. With what speed would it fly if M = 1?

A smooth 10-cm-diameter sphere weighs 6 N. If it is dropped in 5 5∘C5 ^ { \circ } \mathrm { C }5∘C C water, its terminal velocity will be nearest:

The drag on a blunt object is due primarily to:

A tall cell-phone tower is 12 cm in diameter over much of the height. A wind blows at 25 m/s. The frequency of the vortices being shed from the tower is nearest:

The shear velocity in the 60-mm-diameter horizontal water pipe of Problem 2 is nearest:

One liter of 20∘C20 ^ { \circ } \mathrm { C }20∘C C water is collected from a 60-cm-long, 4-mm-diameter tube over a time span of 4 minutes. The length of the entrance region is nearest:

The free-stream flow outside a boundary layer is:

The horsepower required to rotate the shaft of Problem 2, if SAE-30 oil at 40 40∘C40 ^ { \circ } \mathrm { C }40∘C ills the gap, is nearest:

Water at 20 20∘C20 ^ { \circ } \mathrm { C }20∘C C flows between 80-cm-wide horizontal parallel plates 12 mm apart such that a pressure drop of 100 Pa occurs over a distance of 2 m. If the top plate is moving at 1.8 m/s inThe direction of the flow, the flow rate is nearest:

\text {Water at 20 ^ { \circ } \mathrm { C } is transported in a 10 -cm-diameter cast iron horizontal pipe at a flow rate of}\text { 0.02 \mathrm {~m} ^ { 3 } / \mathrm { s }. The pressure drop over \(100 \mathrm {~m}\) of the pipe is nearest:}

In which one of the following flows must compressibility be considered?

Basic Considerations

Fluid Statics

Introduction to Fluids in Motion

The Integral Forms of the Fundamental Laws

The Differential Forms of the Fundamental Laws

Dimensional Analysis and Similitude

Internal Flows

External Flows

Compressible Flow

Flow in Open Channels

Flows in Piping Systems

Turbomachinery

Measurements in Fluid Mechanics

Computational Fluid Dynamics

Filters

A smooth 10-cm-diameter sphere weighs 6 N. If it is dropped in 5 $5 ^ { \circ } \mathrm { C }$ C water, its terminal velocity will be nearest:

One liter of $20 ^ { \circ } \mathrm { C }$ C water is collected from a 60-cm-long, 4-mm-diameter tube over a time span of 4 minutes. The length of the entrance region is nearest:

The horsepower required to rotate the shaft of Problem 2, if SAE-30 oil at 40 $40 ^ { \circ } \mathrm { C }$ ills the gap, is nearest:

Water at 20 $20 ^ { \circ } \mathrm { C }$ C flows between 80-cm-wide horizontal parallel plates 12 mm apart such that a pressure drop of 100 Pa occurs over a distance of 2 m. If the top plate is moving at 1.8 m/s inThe direction of the flow, the flow rate is nearest:

$\text {Water at 20 ^ { \circ } \mathrm { C } is transported in a 10 -cm-diameter cast iron horizontal pipe at a flow rate of}$ $\text { 0.02 \mathrm {~m} ^ { 3 } / \mathrm { s }. The pressure drop over \(100 \mathrm {~m}\) of the pipe is nearest:}$