Supersonic Wind and Imaging Flow Tunnel

Supersonic Wind and Supersonic Wind and Imaging Flow TunnelImaging Flow Tunnel

•Kendria AltKendria Alt•Joshua ClementJoshua Clement•Shannon FortenberryShannon Fortenberry•Katelynn GreerKatelynn Greer

•David McNeill David McNeill •Charlie Murphy Charlie Murphy •Matthew OsbornMatthew Osborn•David SpringerDavid Springer

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ContentContent

• BackgroundBackground• ObjectiveObjective• Tunnel DesignTunnel Design• Visualization DesignVisualization Design• Current ConfigurationCurrent Configuration• Project ManagementProject Management

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ObjectiveObjective

• Supersonic wind tunnel and flow Supersonic wind tunnel and flow visualization system visualization system

• Operable by engineering Operable by engineering undergraduatesundergraduates

• Mach 1.5 – 3 in 0.5 incrementsMach 1.5 – 3 in 0.5 increments• Mach ±0.05 accuracyMach ±0.05 accuracy

• Customer: Dr. Brian ArgrowCustomer: Dr. Brian Argrow

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BackgroundBackground

• Project attempted 6 years agoProject attempted 6 years ago– Failed due to choked flow before nozzleFailed due to choked flow before nozzle

• Commercially available supersonic wind Commercially available supersonic wind tunnelstunnels– Aerolab 1” x 1” with Schlieren and 4 modelsAerolab 1” x 1” with Schlieren and 4 models

• $127,213.00 $127,213.00 • Footprint ≈ 30 ftFootprint ≈ 30 ft22

• Noise ≈ 120 dBNoise ≈ 120 dB

• Commercially available Schlieren systemCommercially available Schlieren system– Focal length longer than cart topFocal length longer than cart top– Low qualityLow quality– Edmund OpticsEdmund Optics

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RequirementsRequirements

•SpeedsSpeeds– Mach 1.5 - 3.0Mach 1.5 - 3.0– ±0.05±0.05

•Steady State Run TimeSteady State Run Time– 5 sec5 sec

•Lab SessionLab Session– 12 runs at Mach 2 12 runs at Mach 2 without changing tankswithout changing tanks– 1 run in 30 min1 run in 30 min– Operable in Operable in temperatures of 20temperatures of 20oo - 80 - 80oo FF

•Size and WeightSize and Weight– Volume < 30” x 42” x Volume < 30” x 42” x 36”36”– Weight < 100 lbs/cart Weight < 100 lbs/cart toptop– 2 cart tops available2 cart tops available

•VisualizationVisualization– Used for Mach Used for Mach verificationverification– Must see aerodynamic Must see aerodynamic phenomena at front and phenomena at front and back of test objectback of test object

•Test SectionTest Section– Area ≥ 1” x 0.25”Area ≥ 1” x 0.25”– Test 3 objects at all Test 3 objects at all speedsspeeds

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Tunnel SystemTunnel System

Matt OsbornMatt OsbornDavid SpringerDavid Springer

**Conceptual Representation Only

Pressure

Reservoir

Valve

Regulator

Settling Tank

Nozzle and Test Section

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Tunnel Decision FlowdownTunnel Decision Flowdown

Pressure Reservoir

VR

ST

Conceptual Representation Only

Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves

1 ValveNo Flow Regulators

Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Vacuum

Gas Nitrogen

Liquid Nitrogen

Grade 705 Zirconium

InvarTitanium Beta

IIIK300 Nickle

Flange / Bolts Clamps

Slip Connector

Round Nozzle / Pipe

Threading

12 Nozzle / Test Sections

4 Nozzles and 3 Test Sections

Plexiglass Glass Polycarbonate

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Tunnel Configuration AlternativesTunnel Configuration Alternatives

Pressure Reservoir

VR

ST


Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves


Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Vacuum

Gas Nitrogen

Liquid Nitrogen

Grade 705 Zirconium

InvarTitanium Beta

IIIK300 Nickle


Slip Connector

Round Nozzle / Pipe

Threading




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Tunnel Configuration AlternativesTunnel Configuration Alternatives

Nozzle

AtmosphereAtmosphere

Compressor

Steady StateSteady State (Appendix B)(Appendix B)

Not FeasibleNot Feasible

• Too large of a compressor at Too large of a compressor at Mach 3Mach 3

• ComplicatedComplicated

Vacuum Reservoir

V

Nozzle


Vacuum TunnelVacuum Tunnel (Appendix B)(Appendix B)

Not FeasibleNot Feasible

• Huge 21 ftHuge 21 ft33 required required• Need large vacuum pumpNeed large vacuum pump• Condensation and IcingCondensation and Icing

Pressure Reservoir

V

Nozzle


Blowdown TunnelBlowdown Tunnel((Appendix B)Appendix B)

• Much smaller reservoir (high pressure)Much smaller reservoir (high pressure)• No condensation or icingNo condensation or icing• Commercial gas (no pumps)Commercial gas (no pumps)

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Initial Analysis ConclusionsInitial Analysis Conclusions

Property UnitsMach Number

1.50 3.00

Test Section Size [in by 0.25 in] 1.00 1.00

Nozzle Size [in by 0.25 in] 0.85 0.24

Nozzle Tolerance [in] 0.0488 0.0225

Nozzle Temperature [deg R] 444.2 447.2

Test Section Temp. [deg R] 367.6 190.4

Temperature Difference [deg R] 76.6 256.8

Static Pressure [psi] 43.2 432.6

Mass Flow [slugs/s] 0.0066 0.0183

Full Mach Range

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Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves


Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Vacuum Gas Nitrogen

Liquid Nitrogen

Grade 705 Zirconium

InvarTitanium Beta

IIIK300 Nickle


Slip Connector

Round Nozzle / Pipe

Threading




Gas SelectionGas Selection

Pressure Reservoir

VR

ST


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Gas SelectionGas Selection

Air N2 O2 He

Weight Score Score Score Score

Safety 35% 3 3.25 0.5 3.25

Cost 25% 3 3.25 3.25 0.5

Mass Flow

20% 2 2 1 5

Mass per Tank

20% 3 3 3.5 0.5

Total 100% 2.76 2.92 1.81 2.32

Specifics

•Oxygen eliminated on safety

•Nitrogen selected over air based on cost

• 2200 psi: $6.45

• 3500 psi: $138

• 6000 psi: $198Conclusions

Nitrogen available in both liquid and gaseous forms. Purchase through AirGas or on campus.

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Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves


Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Vacuum

Gas Nitrogen

Liquid Nitrogen

Grade 705 Zirconium

InvarTitanium Beta

IIIK300 Nickle


Slip Connector

Round Nozzle / Pipe

Threading




Liquid vs. Gas NitrogenLiquid vs. Gas Nitrogen

Pressure Reservoir

VR

ST


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Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves

1 Valve

No Flow Regulators

Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Vacuum

Gas Nitrogen

Liquid Nitrogen

Grade 705 Zirconium

InvarTitanium Beta

IIIK300 Nickle


Slip Connector

Round Nozzle / Pipe

Threading




Regulators vs. Second TankRegulators vs. Second Tank

Pressure Reservoir

VR

ST


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Regulators vs. Second TankRegulators vs. Second Tank

Conceptual Representations Only

R R

R R

R RR R V

R

V

V

8 Tanks – 8 Regulators 8 Tanks – 8 Regulators • RequirementRequirement

– 0.0183 slugs/s → 29,000 scfh0.0183 slugs/s → 29,000 scfh• Tanks: 4000 scfhTanks: 4000 scfh

– Minimum 8 tanksMinimum 8 tanks• Regulators: 6000 scfhRegulators: 6000 scfh

– Minimum 6 regulatorsMinimum 6 regulators– Each regulator > $300Each regulator > $300

• 48 Runs at Mach 248 Runs at Mach 2• Constant test section propertiesConstant test section properties

8 Tanks – 1 Regulator – Second Tank – 2 8 Tanks – 1 Regulator – Second Tank – 2 ValvesValves

• Second tankSecond tank– 4 cubic feet @ 1000 psi maximum4 cubic feet @ 1000 psi maximum– Can manufacture for ~ $700Can manufacture for ~ $700

• 12 Runs at Mach 212 Runs at Mach 2• Properties in test section changeProperties in test section change

Appendix C

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Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves


Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Vacuum

Gas Nitrogen

Liquid Nitrogen

Grade 705 Zirconium

InvarTitanium Beta

IIIK300 Nickle


Slip Connector

Round Nozzle / Pipe

Threading




Liquid vs. Gaseous NitrogenLiquid vs. Gaseous Nitrogen

Pressure Reservoir

VR

ST


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Liquid vs. Gaseous NitrogenLiquid vs. Gaseous Nitrogen

R

V

V

V

V

• Gaseous NitrogenGaseous Nitrogen– 8 Tanks – One Regulator – Two Gaseous Valves8 Tanks – One Regulator – Two Gaseous Valves– 8 Hoses and Manifold – Complicated ($$)8 Hoses and Manifold – Complicated ($$)

• Liquid NitrogenLiquid Nitrogen– 1 Tank –Cryogenic Valve – Heater Element – 1 Tank –Cryogenic Valve – Heater Element –

Gaseous ValveGaseous Valve– Hours of run timeHours of run time– 11,430.67 BTU/hr → $200 heater11,430.67 BTU/hr → $200 heater– Liquid Nitrogen available on campusLiquid Nitrogen available on campus– Thermal Fatigue on 2Thermal Fatigue on 2ndnd Tank Tank

• Currently not enough information to Currently not enough information to decidedecide– Parallel PathsParallel Paths– Drop Dead Date of Oct. 26Drop Dead Date of Oct. 26

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Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves


Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Plexiglass

Vacuum

Gas Nitrogen

Liquid Nitrogen

Glass Polycarbonate


Slip Connector

Round Nozzle / Pipe

Threading



Grade 705 Zirconium

InvarTitanium Beta III

K300 Nickle

Nozzle MaterialNozzle Material

Pressure Reservoir

VR

ST


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Nozzle Material SelectionNozzle Material Selection

V∞

Not to Scale

•Temperature differences at throat and test section• Contraction differences modify Mach number

447.2°R

190.4°R

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Nozzle Material SelectionNozzle Material Selection

Ti-BetaIII

InvarK-300

NiGrade 705 Zr


CTE 60% 0.8 4.2 2.1 2.9

σ/ρ 20% 4.1 1.7 2.5 1.7

Cost 10% 2.1 1.3 3.7 2.9

Hard 10% 1.7 2.5 2.5 3.3

Total 100% 1.7 3.2 2.4 2.7

Specifics

• CTE: Coefficient of Thermal Expansion

• Specific Strength: lightweight under pressure

• Hardness affects machinability

•Assumed 120 sec of continuous Mach 2 flow Conclusions

• Sensitivity analysis supports Invar for CTE > 43%

Material Specs: Appendix D

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Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves


Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Plexiglass

Vacuum

Gas Nitrogen

Liquid Nitrogen

Glass Polycarbonate


Slip Connector

Round Nozzle / Pipe

Threading



Grade 705 Zirconium

InvarTitanium Beta

IIIK300 Nickle

Test Section SidewallTest Section Sidewall

Pressure Reservoir

VR

ST


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Test Section Material SelectionTest Section Material Selection

• Test section cross sectionTest section cross section

• Grey: Transparent windows Grey: Transparent windows

• Green: MetalGreen: Metal

• Materials contract at different Materials contract at different ratesrates

Not to Scale

190.4°R

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Test Section Material SelectionTest Section Material Selection

Glass Plexiglass Polycarbonate

Weight Score Score Score

k 20% 1.7 4.4 3.9

n 20% 5 2.2 2.8

CTE 15% 5.5 2.5 2

% Visible 15% 2.8 3.9 3.3

σ/ρ 15% 1.7 3.9 4.4

Cost 10% 3.1 3.9 3

Hard 5% 4.5 3.3 2.2

Total 100% 3.37 3.42 3.21

Specifics

• k: Conductivity affects condensation

• n: Refractive Index - visualization

• % Visible - transparency

• Hardness - scratch resistance

•Assumed 120 sec of continuous Mach 2 flow

Conclusions

• Sensitivity analysis shows Plexiglass and Glass ~50/50

Material Specs : Appendix D

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Tunnel Decisions

Steady State

Blowdown

Commercial Gas

Compressor

Oxygen

Air

Helium

Nitrogen

Gas Nitrogen

Liquid Nitrogen

Multiple Valves


Flow Regulators

Direct

Second Tank

No Regulator

Regulator Between

Tanks

Plexiglass

Vacuum

Gas Nitrogen

Liquid Nitrogen

Glass Polycarbonate


Slip ConnectorRound Nozzle / Pipe Threading



Grade 705 Zirconium

InvarTitanium Beta

IIIK300 Nickle

Test Section / Nozzle Test Section / Nozzle StructureStructure

Pressure Reservoir

VR

ST


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Test Section / Nozzle Test Section / Nozzle StructureStructure

• Requirement: 3 objects, 4 Mach numbers Requirement: 3 objects, 4 Mach numbers eacheach

• Test Section/Nozzle configurationTest Section/Nozzle configuration– 4 Nozzles with 3 interchangeable test sections4 Nozzles with 3 interchangeable test sections– 12 Fixed nozzle / test section combos12 Fixed nozzle / test section combos

• Less complexLess complex

• Nozzle / Settling Tank ConnectionNozzle / Settling Tank Connection– Round nozzle w/ pipe threadsRound nozzle w/ pipe threads– Slip connectorSlip connector– Flanges w/ clampsFlanges w/ clamps

• Easy to useEasy to use• Quick change out of nozzleQuick change out of nozzle

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Additional Requirements & Additional Requirements & RisksRisks

• Noise ConstraintsNoise Constraints– EH&S guidelinesEH&S guidelines– 85 dB85 dB

• Ability to TroubleshootAbility to Troubleshoot– In the event of initial failure to achieve supersonic In the event of initial failure to achieve supersonic

flowflow– Reservoir pressure and temperature Reservoir pressure and temperature

measurements measurements

• RisksRisks– BudgetBudget– ManufacturingManufacturing– SafetySafety

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NoiseNoise

•RequirementRequirement– 85 dB at 85 dB at WalkwaysWalkways– 20 - 30 ft from 20 - 30 ft from tunneltunnel

SolutionSolution• Noise is DirectionalNoise is Directional

– Small half boothSmall half booth

• AcousticAcoustic FoamsFoams– 2 - 4” thick2 - 4” thick– NRC 0.8 - 1.25NRC 0.8 - 1.25

• HighHigh DensityDensity VinylVinyl BarriersBarriers

– STC 27 - 32STC 27 - 32

• Foam - Vinyl Foam - Vinyl CompositesComposites

•EmpiricalEmpirical DataData– 65 -160 dB65 -160 dB

• Test section Test section 20x30 mm to 2x2 20x30 mm to 2x2 mm• 0.8 < M < 80.8 < M < 8

Ref [7]

Ref [7]

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Troubleshooting Troubleshooting InstrumentationInstrumentation

• Settling Tank Settling Tank ThermocoupleThermocouple– Easily integrated with LabViewEasily integrated with LabView– K typeK type– NPT fitting for pressure vesselsNPT fitting for pressure vessels

• Settling Tank Pressure Settling Tank Pressure TransducerTransducer– Commercially availableCommercially available– CompactCompact– Easily integrated with LabViewEasily integrated with LabView– 0 - 2000 psi0 - 2000 psi– NPT fittingNPT fitting

• Pitot TubePitot Tube Appendix EAppendix E

Ref [8]

Ref [9]

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Tunnel RisksTunnel Risks

CCoonnsseeqquueennccee

55 Cost

44 Nozzle Design

LN2 Heater

Settling Tank

Thermal Fatigue

Cryogenic Valve

33Machining Tolerances

Settling Tank

22 Volume

Constraint

11 Connections

11 22 33 44 55

LikelihoodLikelihood

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Tunnel RiskTunnel Risk• Liquid Nitrogen Heater (11/01)Liquid Nitrogen Heater (11/01)

– Inadequate specificationsInadequate specifications– Thoroughly research heater optionsThoroughly research heater options

• Settling Tank Design and Thermal Fatigue (10/26)Settling Tank Design and Thermal Fatigue (10/26)– Inadequate specifications and costInadequate specifications and cost

• Custom or in-houseCustom or in-house– Contact vendors and Matt RhodeContact vendors and Matt Rhode

• Cryogenic Valve (10/26)Cryogenic Valve (10/26)– Inadequate specificationsInadequate specifications– Continue dialog with AirGas vendorContinue dialog with AirGas vendor

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Visualization SystemVisualization System

Kendria AltKendria AltJosh ClementJosh Clement

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Visualization Decision Visualization Decision FlowdownFlowdown

VisualizationSystem

Interferometer

Shadowgraph

Achromatic Objective

Achromatic

Focusing

Fixed Lens

MountDouble Pass

StraightSchlieren

Z

Horseshoe

Radial Color

Cart BaseStructure

AdjustableLens

Mount

Vertical Black and

White

Horizontal Black and

White

Linear Color

Metal Foundation

PlasticFoundation

CCD FILMCMOS

Commercial Mount

Manufactured Mount

2-Axis Adjustable

3-Axis Adjustable

Knife Edge / Filter

Interchange

Knife Edge Only

3-Axis Adjustable

2-Axis Adjustable

FireWire GPIB USB Ethernet

Plastic Encasing

Aluminum Encasing

Wooden Encasing

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Schlieren, Shadowgraph, Schlieren, Shadowgraph, InterferometerInterferometer

VisualizationSystem

Interferometer

Shadowgraph


Achromatic

Focusing

Fixed Lens

MountDouble Pass

StraightSchlieren

Z

Horseshoe

Radial Color

Cart BaseStructure

AdjustableLens

Mount

Vertical Black and

White


White

Linear Color

Metal Foundation

PlasticFoundation

CCD FILMCMOS

Commercial Mount

Manufactured Mount

2-Axis Adjustable

3-Axis Adjustable

Knife Edge / Filter

Interchange

Knife Edge Only

3-Axis Adjustable

2-Axis Adjustable


Plastic Encasing

Aluminum Encasing

Wooden Encasing

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Schlieren, Shadowgraph, Schlieren, Shadowgraph, InterferometerInterferometer

• Shadow GraphShadow Graph– 22ndnd derivative of density derivative of density– Simplest methodSimplest method– Lower contrastLower contrast

• SchlierenSchlieren– 11st st derivative of densityderivative of density– Small increase in complexitySmall increase in complexity– Increase in contrast Increase in contrast

• InterferometerInterferometer– DensityDensity– Sum of path differences < Sum of path differences < λλ

/10/10thth

– Least familiarityLeast familiarity

Example Pictures: Appendix F

Ref [1]Home

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Schlieren LayoutSchlieren Layout

VisualizationSystem

Interferometer

Shadowgraph


Achromatic

Focusing

Fixed Lens

Mount

Double Pass

StraightSchlieren

Z

Horseshoe

Radial Color

Cart BaseStructure

AdjustableLens

Mount

Vertical Black and

White


White

Linear Color

Metal Foundation

PlasticFoundation

CCD FILMCMOS

Commercial Mount

Manufactured Mount

2-Axis Adjustable

3-Axis Adjustable

Knife Edge / Filter

Interchange

Knife Edge Only

3-Axis Adjustable

2-Axis Adjustable


Plastic Encasing

Aluminum Encasing

Wooden Encasing

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Schlieren LayoutsSchlieren Layouts• Z

• Precise angles prevent coma aberration• Large footprint

•Double Pass• Nonparallel light in test section• Advantage of size

•Straight Schlieren

• Smaller focal length• Ease of integration

Ref [2]

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Schlieren LayoutSchlieren Layout

Double Pass

ZHorsesho

eStraight

Weight ScoreScor

eScore Score

Clarity 35% 1 4 1 4

Size 20% 3 2 1 4

Setup 15% 3 1 2 4

Stability 10% 3 1.5 1.5 4

Cost 10% 4 2 2 2

Time to Build

5% 3 2 2 3

Ease of Design

5% 4 2 1 3

Total 100% 2.45 2.5 1.35 3.7

Specifics• Clarity: most important, verification

• Size: must be able to fit on cart top

• Stability: must be able to withstand movement without quality loss

•Time to build: number of parts, complexity, and tolerances

•Ease of design: depth of calculations

Conclusions

•Straight setup has high accuracy and small footprint

•Straight setup is easy to use and calibrateHome

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Visualization Decision Visualization Decision FlowdownFlowdown

VisualizationSystem

Interferometer

Shadowgraph


Achromatic

Focusing

Fixed Lens Mount

Double Pass

StraightSchlieren

Z

Horseshoe

Radial Color

Cart BaseStructure

AdjustableLens Mount

Vertical Black and

White


White

Linear Color

Metal Foundation

PlasticFoundation

CCD FILMCMOS

Commercial Mount

Manufactured Mount

2-Axis Adjustable

3-Axis Adjustable

Knife Edge / Filter

Interchange

Knife Edge Only

3-Axis Adjustable

2-Axis Adjustable


Plastic Encasing

Aluminum Encasing

Wooden Encasing

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LensesLenses• TypesTypes

– Focusing LensFocusing Lens• Different wavelengths have different focal lengthsDifferent wavelengths have different focal lengths

– Achromatic LensAchromatic Lens• Reduces chromatic aberrationReduces chromatic aberration• Dual lensesDual lenses

– Achromatic Objective LensAchromatic Objective Lens• Changes orientation of aberrationsChanges orientation of aberrations• Two lenses separated by air or oilTwo lenses separated by air or oil• Expensive ~$500 to $1000Expensive ~$500 to $1000

• SpecificationsSpecifications– Diameter: 3 inDiameter: 3 in– Focal Length: 0 to 6 inFocal Length: 0 to 6 in

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Refraction Detection MethodRefraction Detection Method

VisualizationSystem

Interferometer

Shadowgraph


Achromatic

Focusing

Fixed Lens

MountDouble Pass

StraightSchlieren

Z

Horseshoe

Radial Color

Cart BaseStructure

AdjustableLens

Mount

Vertical Black and White


WhiteLinear Color

Metal Foundation

PlasticFoundation

CCD FILMCMOS

Commercial Mount

Manufactured Mount

2-Axis Adjustable

3-Axis Adjustable

Knife Edge / Filter

Interchange

Knife Edge Only

3-Axis Adjustable

2-Axis Adjustable


Plastic Encasing

Aluminum Encasing

Wooden Encasing

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Refraction DetectionRefraction Detection• Knife EdgeKnife Edge

– Clear black and white Clear black and white visualizationvisualization

– Vertical or horizontal Vertical or horizontal placement show different placement show different detailsdetails

• Radial Color FilterRadial Color Filter– Density variations stand Density variations stand

outout• Linear Color FilterLinear Color Filter

– Provides color and intensity Provides color and intensity differences for high and differences for high and low densitieslow densities

Ref [14 ]

Ref [15 ]

Ref [16 ]

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Refraction DetectionRefraction Detection

• Manual Three Axis SupportManual Three Axis Support– Easy calibration within 7.87 10Easy calibration within 7.87 10-5-5 in in– Calibration performed once per semesterCalibration performed once per semester– Cost ~ $500Cost ~ $500

• Motorized MountsMotorized Mounts– Expensive ~ $1000Expensive ~ $1000– Accurate to 3.94 10Accurate to 3.94 10-3-3 in in

• InterchangeInterchange– Provide 3 filters for the 4 visualization methodsProvide 3 filters for the 4 visualization methods– Filters mount on a 3-axis adjustable supportFilters mount on a 3-axis adjustable support

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Capture MethodCapture Method

VisualizationSystem

Interferometer

Shadowgraph


Achromatic

Focusing

Fixed Lens

MountDouble Pass

StraightSchlieren

Z

Horseshoe

Radial Color

Cart BaseStructure

AdjustableLens

Mount

Vertical Black and

White


White

Linear Color

Metal Foundation

PlasticFoundation

CCD FILMCMOS

Commercial Mount

Manufactured Mount

2-Axis Adjustable

3-Axis Adjustable

Knife Edge / Filter

Interchange

Knife Edge Only

3-Axis Adjustable

2-Axis Adjustable


Plastic Encasing

Aluminum Encasing

Wooden Encasing

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Capture MethodCapture Method

Film CMOS CCD

Weight Score Score Score

Frame/sec 30% 1 4.5 4.5

Remote Control 30% 0.5 4.75 4.75

Resolution 20% 5 2.5 2.5

Cost 20% 3.12 3.12 3.76

Total 100% 2.1 3.9 4.0

Specifics•Requirement: 2 fps

•Resolution normalized to 3 Mega pixels

•Frames per second normalized to 20 fps

•Prices normalized to a $1500 camera

Conclusions

•CMOS and CCD comparable

•Final decision based on individual specifications

Ref [18]

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File Transfer MethodFile Transfer Method

USB GPIB FireWire Ethernet


LabStation Compatibility

30% 3.5 3.5 2 1

Cost 30% 3 2.5 3 1.5

LabView Compatibility

20% 2 2.5 5 0.5

Cable 10% 3 2.5 2 2.5

Speed 10% 2.5 1 5 1.5

Total 100% 3 2.55 3.2 1.25

Specifics• Speed normalized to 10 Mbytes/s

• Cable cost includes max length and durability

• Only USB and GPIB are immediately compatible with LS

• FireWire cards $50

• Ethernet activation- $350

Conclusions

• The ideal file transfer method will be FireWire

• Other constraints may require a less desirable method

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Camera AdjustabilityCamera Adjustability

• 2-Axis Adjustability2-Axis Adjustability – Ability to focus 3Ability to focus 3rdrd dimension with camera dimension with camera– Ease of useEase of use– LockingLocking

• Commercial MountCommercial Mount– Expensive ~ $350Expensive ~ $350

• Custom MountCustom Mount– Complicated designComplicated design– Intricate FabricationIntricate Fabrication Ref [12]

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Schlieren Base and EncasingSchlieren Base and Encasing

VisualizationSystem

Interferometer

Shadowgraph


Achromatic

Focusing

Fixed Lens

MountDouble Pass

StraightSchlieren

Z

Horseshoe

Radial Color

Cart BaseStructure

AdjustableLens

Mount

Vertical Black and

White


White

Linear Color

Metal Foundation

PlasticFoundation

CCD FILMCMOS

Commercial Mount

Manufactured Mount

2-Axis Adjustable

3-Axis Adjustable

Knife Edge / Filter

Interchange

Knife Edge Only

3-Axis Adjustable

2-Axis Adjustable


Plastic Encasing

Aluminum Encasing

Wooden Encasing

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Schlieren Base and Schlieren Base and EncasingEncasing

• BaseBase– Use the cart topUse the cart top– Use a metal foundation to secure optical Use a metal foundation to secure optical

componentscomponents• EncasingEncasing

– Plastic is light and inexpensivePlastic is light and inexpensive• Metal and wood heavyMetal and wood heavy

– Protection of lenses and cameraProtection of lenses and camera • StudentsStudents• Dust, scratches, etc.Dust, scratches, etc.

– Light tight during testingLight tight during testing– Window for educational purposeWindow for educational purpose– Opening for T.A.s to access instrumentationOpening for T.A.s to access instrumentation

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Visualization RisksVisualization Risks

Consequence

5 Lenses

4 Internal Interference

Aberration

3 Optical Mounts Camera

2 External

Interference

1 Calibration Encasing

1 2 3 4 5

Likelihood

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Current ConfigurationCurrent Configuration

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Cost EstimatesCost EstimatesItem Qua Price Cost

Schlieren

Visualization System

CCD Camera PL-A781/2 1 1,583.00 1,583.00

Achromatic Objective Lenses 2 700.00 1,400.00

Optical Cell Mounts 3" 2 20.00 40.00

Knife Edge 1 10.00 10.00

Knife Edge Mount 1 295.00 295.00

Student Made Color Filter 2 10.00 20.00

Light source (straight filament) 1 4.99 4.99

Light mount with slit 1 10.00 10.00

Structure and Encasing

Aluminum Stock for machining mounts 1 9.19 9.19

Black Plexiglas sheet 12x12 (10 sheets) 1 46.90 46.90

Aluminum 1" square tubing 1 143.46 143.46

Box of 25 head machine Skews 1 8.33 8.33

Black Silicone cocking 1 1.95 1.95

Misc.

Prototype 1 100.00 100.00

Gas

Nitrogen tank 16 6.51 104.16

Settling Tank 1 500.00 500.00

Pressure Regulator 1 200.00 200.00

Linkages 15 20.00 300.00

Insulated Tubing (60 feet) 1 100.00 100.00

Manual On/Off Valve 1 150.00 150.00

Pneumatic Valve 1 795.00 795.00

Wind tunnel

12 Nozzles @ 6x2x2

Stock Invar @ 6x6x1 4 185.00 740.00

Spare Invar Stock 2 185.00 370.00

Mills 2 28.45 56.89

12 Test Sections @ 3x2

Stock Invar @ 6x6x1 1 185.00 185.00

Optical Grade Polycarbonate @ 3x2x0.5 24 3.00 72.00

Spare Polycarbonate 4 3.00 12.00

O rings 40 0.50 20.00

Misc.

Sound Booth 1 100.00 100.00

100 1/8" Bolts 3 15.00 45.00

100 1/8" Nuts 3 12.00 36.00

100 1/8" Washers 3 12.00 36.00

Data Collection

Pressure Transducers 1 205.00 205.00

Thermocouples 1 35.00 35.00

Additional Hardware 1 100.00 100.00

TOTAL +25% $9,134.21

Initial Total $7,534.87Contingency (25%) $1,883.72TOTALTOTAL$9,418.59$9,418.59Applying for UROP, EFF, Department and Dean’s Fund resources.

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52

Base DeliverablesBase Deliverables

Base: Base: $4000$4000

Consequence Consequence

2 Invar Nozzles / Test Sections2 Invar Nozzles / Test Sections Mach Accuracy not guaranteed at Mach Accuracy not guaranteed at all temperaturesall temperatures

Linkages for 1 tankLinkages for 1 tank Only 1 run tank, wastefulOnly 1 run tank, wasteful

1 Settling Tank1 Settling Tank

1 Manual Valve1 Manual Valve No one button start / stopNo one button start / stop

1 Pressure Regulator1 Pressure Regulator

1 Low Resolution Camera1 Low Resolution Camera Difficult Mach MeasurementDifficult Mach Measurement

Can not verify Mach accuracyCan not verify Mach accuracy1 Pair Low Quality Mirrors1 Pair Low Quality Mirrors

1 Set Fabricated Optical Mounts1 Set Fabricated Optical Mounts No guarantee on performance or No guarantee on performance or durabilitydurability

1 Knife Edge1 Knife Edge Black and White Schlieren OnlyBlack and White Schlieren Only

Fabricated Color FilterFabricated Color Filter

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Deliverable UpgradesDeliverable Upgrades

Base: $4000Base: $4000 Additional CostAdditional Cost

Additional Nozzles and Test SectionsAdditional Nozzles and Test Sections $77.10 each$77.10 each

Manifold to accommodate 8 tanksManifold to accommodate 8 tanks $300$300

1 Pneumatic Valve1 Pneumatic Valve $800$800

1 Pair High Quality Lenses1 Pair High Quality Lenses $712$712

1 High Resolution Camera1 High Resolution Camera $900$900

Commercial Knife Edge MountsCommercial Knife Edge Mounts $300$300

Settling Tank Pressure and Temperature SensorsSettling Tank Pressure and Temperature Sensors $340$340

Storage Case for Test Sections and Optical Storage Case for Test Sections and Optical ComponentsComponents $280$280

Commercial Color FilterCommercial Color Filter $710$710

Commercial Lens and Camera MountsCommercial Lens and Camera Mounts $500$500

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54

SWIFTSWIFTResponsibility BreakdownResponsibility Breakdown

Project ManagerDavid McNeill

Systems EngineerShannon Fortenberry

CFOKendria Alt

Fabrication EngineerCharlie Murphy (WT)Katelynn Greer (Vis)

Safety EngineerDavid Springer

Web MasterMatt Osborn

Human FactorsJoshua Clement

Tunnel Team

Visualization Team

Aerodynamics LeadMatt Osborn

Structure LeadDavid Springer

Gas LeadShannon Fortenberry

Electronics LeadCharlie Murphy

Structure LeadKendria Alt

Capture LeadKatelynn Greer

Optics LeadJoshua Clement

Assistant Project ManagerMatt Osborn

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Tunnel Team Tunnel Team Responsibility BreakdownResponsibility Breakdown

Tunnel Team

Fluid

Structure

Aerodynamics

Nozzle / Test Section

Settling Tube

Dimensions

Object Placement

Velocity

Size

Straightening

Selection

Quantity

Phase

Transportation

Regulation

Heat Addition

Cost

Valves

Nozzle, TS, Settling Tube

AcousticEnclosure

Material

Thermal Contraction

Nozzle / Settling Tube Interface

Material

Support

Transfer Method

Transparency

Electronics

Storage Vessel

Tubing

Linkages

Massflow

Pressure / Temp.

Type

Acoustics

Diffuser

Pressure Capacity

Computer Interface

Fluid Heater

Settling TubeSensing

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Visualization Team Visualization Team Responsibility BreakdownResponsibility Breakdown

Visualization Team

Structures

Capture

Optics

Layout

Lens/Mirror

Filtration

Sensitivity

Size

Focal Length

Reflectivity

Size

Neccessity

Mirror Support

Protection

Purchase / Fabricate

Transparency

Pointing Accuracy

Camera / Knife Edge Support

Adjustment

Pointing Tolerance

Strength

Collapsibility

TS / Protection Interface

Purchase / Fabricate

Method

Electronics

Resolution

Frames / Sec

Cost

Transfer Rate

Camera Control

Light Source

Transfer Method

Sensitivity

Method

Aperture

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Semester ScheduleSemester Schedule

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Spring ScheduleSpring Schedule

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59

ReferencesReferences1.1. Merzkirch, Wolfgang. Merzkirch, Wolfgang. Flow VisualizationFlow Visualization. New York: . New York:

Academic P, 1974. 62-115. Academic P, 1974. 62-115. 2.2. Smits, A. J., and T. T. Lim. Smits, A. J., and T. T. Lim. Flow Visualization Techniques Flow Visualization Techniques

and Examplesand Examples. Covent Garden: Imperial College P, 2000. . Covent Garden: Imperial College P, 2000. 205-243205-243

3.3. Shevell, Richard S. Shevell, Richard S. Fundamentals of FlightFundamentals of Flight. 2nd ed. Upper . 2nd ed. Upper Saddle River: Prentice Hall, 1989Saddle River: Prentice Hall, 1989

4.4. Wikipedia.orgWikipedia.org5.5. http://not2fast.wryday.com/turbo/glossary/turbo_calc.shtmlhttp://not2fast.wryday.com/turbo/glossary/turbo_calc.shtml6.6. NACA TN No. 1651, NACA TN No. 1651,

http://naca.larc.nasa.gov/reports/1948/naca-tn-1651/, http://naca.larc.nasa.gov/reports/1948/naca-tn-1651/, accessed: 09/25/2006accessed: 09/25/2006

7.7. Matweb.comMatweb.com8.8. http://www.omega.com/ppt/pptsc.asp?ref=TC-NPThttp://www.omega.com/ppt/pptsc.asp?ref=TC-NPT9.9. http://www.omega.com/pptst/px302.htmlhttp://www.omega.com/pptst/px302.html10.10. http://www.efunda.com/designstandards/sensors/http://www.efunda.com/designstandards/sensors/

pitot_tubes/pitot_tubes_theory.cfmpitot_tubes/pitot_tubes_theory.cfm

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ReferencesReferences

11.11. Mott, Robert. Mott, Robert. Applied Fluid Mechanics.Applied Fluid Mechanics. 6 6thth ed. Upper ed. Upper Saddle River: Prentice Hall, 2006 (eq 18.14)Saddle River: Prentice Hall, 2006 (eq 18.14)

12.12. http://www.edmundoptics.com/onlinecatalog/http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productID=1580&search=1, displayproduct.cfm?productID=1580&search=1, October 9, 2006October 9, 2006

13.13. http://www.mne.psu.edu/psgdl/FullScaleSchlieren.pdfhttp://www.mne.psu.edu/psgdl/FullScaleSchlieren.pdf14.14. http://www.mne.psu.edu/psgdl/http://www.mne.psu.edu/psgdl/

highspeedshockmovie.pdfhighspeedshockmovie.pdf15.15. http://www.mne.psu.edu/psgdl/ASME_http://www.mne.psu.edu/psgdl/ASME_

%20shockwave.pdf%20shockwave.pdf16.16. http://www.mne.psu.edu/psgdl/FSSISFV7_updated.pdfhttp://www.mne.psu.edu/psgdl/FSSISFV7_updated.pdf17.17. http://www.ioffe.rssi.ru/GASDYN/Image4.jpeghttp://www.ioffe.rssi.ru/GASDYN/Image4.jpeg18.18. http://www.edmundoptics.com/onlinecatalog/http://www.edmundoptics.com/onlinecatalog/

displayproduct.cfm?productID=2716&search=1displayproduct.cfm?productID=2716&search=1

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4. Background

5. RequirementsTunnel7. Tunnel Decision Flowdown9. Tunnel Configuration Alternatives10. Initial Analysis Conclusions12. Gas Selection15. Regulators vs. Second Tank17. Liquid vs. Gaseous Nitrogen19. Nozzle Material Selection (Diagram)20. Nozzle Material Selection (Trade Study)22. Test Section Material Selection (Diagram)23. Test Section Material Selection (Trade Study)25. Test Section/Nozzle Structure26. Additional Requirements & Risks27. Noise28. Troubleshooting Instrumentation29. Tunnel Risks (5x5)30. Tunnel Risk (Mitigations)

Visualization32. Visualization Decision Flowdown34. Schlieren, Shadowgraph, Interferometer36. Schlieren Layouts37. Schlieren Layout (Trade Study)39. Lenses41. Refraction Detection40. Refraction Detection44. Capture Method45. File Transfer Method46. Camera Adjustability48. Schlieren Base and Encasing49. Visualization Risks (5x5)50. Current Configuration

Budget51. Cost Estimates52. Base Deliverables53. Deliverable Upgrades

Team Management54. SWIFT Responsibility Breakdown55. Tunnel Team Responsibility Breakdown56. Visualization Team Responsibility Breakdown57. Semester Schedule58. Spring Schedule

Appendices62. Appendix A Trade Study Sensitivity Analysis63. Appendix B Assumptions and Key Equations64. Appendix B Steady State Tunnel67. Appendix B Vacuum Tunnel69. Appendix B Blowdown Tunnel74. Appendix C Gas Appendices77. Appendix D Material Selection 79. Appendix E Pitot Tube81. Appendix F Visualization Examples83. Appendix G Single Mirror Schlieren84. Appendix H Refraction Detection Focal Length Sensitivity86. Appendix I Measurement Feasibility87. Appendix J Future Consideration Nozzle

62

Appendix AAppendix ATrade Study Sensitivity Trade Study Sensitivity

AnalysisAnalysis

Choice

1Choice

2Choice

3Choice

4


Criteria 1 60% 2 4 3 1

Criteria 2 20% 1 3 2 4

Criteria 3 10% 2 4 3 1

Criteria 4 10% 3 2 4 3

Total 100% 1.9 3.6 2.9 1.8

Analysis

• Sensitivity of weights, not scores

• Lower subjectivity in scores

• Varied weights and recalculated totals

• Investigated weight combinations that yielded different results

Conclusions

• Removed most subjectivity from trade studies

• Result often unchanged Home

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Appendix BAppendix BAssumptions and Key Assumptions and Key

EquationsEquations• AssumptionsAssumptions

(for the preliminary analysis only)(for the preliminary analysis only)

– Isentropic FlowIsentropic Flow– Ideal NozzleIdeal Nozzle– The Gas was Dry AirThe Gas was Dry Air

1120

2

11

ii

M 1

20

2

11

ii

Mp

p

20

2

11 i

iM

T

T

1/12

2

2

* 2

11

1

21

MMA

A

i

i

RTa

iii RTP

iii aMV

iiii AVm

Rslug

lbft 6006)(

Rslug

lbft 1718)(

-airc

-airR

p

condition streamX

condition stagnation

i

0

X

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Appendix B Appendix B Steady State TunnelSteady State Tunnel

• Steady Flow CompressorSteady Flow Compressor– Obtain Compression RatioObtain Compression Ratio

• Axial CompressorAxial Compressor– Used in Jet EnginesUsed in Jet Engines– Expensive and ComplicatedExpensive and Complicated

• Centrifugal CompressorCentrifugal Compressor– TurbochargersTurbochargers– Common and Fairly CheepCommon and Fairly Cheep

Nozzle


Compressor 1

20

2

11

ii

Mp

p

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Appendix B Appendix B Steady State Tunnel at Mach 2Steady State Tunnel at Mach 2

82.7100

atmatm T

T

p

pCPR

Observations

•Pressure Ratio

•7.82

•Test sec. temp. is room temperature

•518.7 ºR

•Energy required is relatively low

•31.1 kW

Need high compression ratio even at Mach 2. At Mach 3, would need a compression ratio of 36.73. Additionally, temperature in the test section is close to room temperature.

kWslug

BTUTTcCW atmp 1.3132010

AxialCompressor

Patm = 2116.2 [lb/ft2]Ρatm = 0.00238 [slugs/ft3]Tatm = 518.69 [ºR]

P0 = 16558 [lb/ft2]ρ0 = 0.1032 [slugs/ft3]T0 = 933.64 [ºR]

M* = 1S* = 0.1481 [in2]

p* = 8747.3 [lb/ft2]ρ* = 0.00654 [slugs/ft3]T* = 778.0 [ºR]

Mt = 2St = 0.25 [in2]

pt = 2116.2 [lb/ft2]ρt = 0.00238 [slugs/ft3]Tt = 518.7 [ºR]

at = 1117.0 [ft/s]Vt = 2233.9 [ft/s]

Test Sectionm=9.21 e-3[slugs/s]

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Appendix B Appendix B Steady State Tunnel at Mach 2Steady State Tunnel at Mach 2

Observations•Question:

Could stock parts from a turbocharger be used?

•Max Compression ~ 3•3 turbos at M=2•12 turbos at M=3

•Mass Flow much larger than needed.

•Cost•$300-1000 per unit

Conclusions

A steady state tunnel is not feasible to meet the requirements. Would need ideally 12 turbos, at Mach 3, in series to meet the mass flow, but the compression ratio probably decreases as p0 goes up.

Ref [4]Ref [5]

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Appendix B Appendix B Vacuum TunnelVacuum Tunnel

• Commonly used in Commonly used in SSWT applicationsSSWT applications

• Vacuum Reservoir must Vacuum Reservoir must be blow atm. pressure.be blow atm. pressure.

• Would to purchase Would to purchase vacuum tanks.vacuum tanks.– Not available from a Not available from a

vendor.vendor.Vacuum Reservoir

V

Nozzle


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Appendix B Appendix B Vacuum Tunnel Mach 2Vacuum Tunnel Mach 2

Observations

•Tt = 288.2 ºR

•Condensation or ice in test section

•Need 21 cubic feet of tank volume for one 10 sec. run

•Need to buy and store

•Need vacuum pump to evacuate air

Conclusions

A vacuum tunnel is not feasible. A custom or multiple stock tanks would need to be purchased, none of which would meet storage requirements. Additional complexity in the vacuum pump, and condensation or icing in the flow tube.

StandardAtmosphere

Settling Reservoir

Vacuum Reservoir

p0 = 2116.2 [lb/ft2]ρ0 = 2.3769e-3 [slugs/ft3]T0 = 518.69 [ºR]

Mt = 2St = 0.25 [in2]

pt = 270.5 [lb/ft2]ρt = 5.47e-4 [slugs/ft3]Tt = 288.2 [ºR]

at = 832.5 [ft/s]Vt = 1665.0 [ft/s]

M* = 1S* = 0.1481 [in2]

p* = 1117.9 [lb/ft2]ρ* = 1.5068e-3 [slugs/ft3]T* = 432.24 [ºR]

m = 1.58 e-3[slugs/s]

TestSection

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Appendix B Appendix B Blowdown TunnelBlowdown Tunnel

• A variety of A variety of drieddried gases feasiblegases feasible– Eliminates icing or Eliminates icing or

condensation issuescondensation issues

• Use commercially Use commercially available tanksavailable tanks– Do not need to Do not need to

storestore– Do not need a Do not need a

compressorcompressor

Pressure Reservoir

V

Nozzle


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Appendix BAppendix BBlowdown Tunnel at Mach 2Blowdown Tunnel at Mach 2

Observations

• One 10 sec run with 3.14 ft3 (one tank and no regulator)

• 12 ten second runs: 2 tanks with regulated flow

M* = 1S* = .1481 [in2]

p* = 8747.3 [lb/ft2]ρ* = 0.0118 [slugs/ft3]T* = 432.2 [ºR]

Mt = 2St = 0.25 [in2]

pt = 2116.2 [lb/ft2]ρt = 0.0043 [slugs/ft3]Tt = 288.2 [ºR]

at = 832.5 [ft/s]Vt = 1665.0 [ft/s]

S0 = 7.06 [in2]

P0 = 16558 [lb/ft2]ρ0 = 0.0186 [slugs/ft3]T0 = 518.69 [ºR]

V0 = 13.5 [ft/s]

ptank = 288000 [lb/ft2]ρtank = 0.3232 [slugs/ft3]Ttank = 518.69 [ºR]

TestSection

m = 0.0124[slugs/s]

PrssureTank

SettlingTube

Conclusions

A blowdown tunnel is feasible. Dried compressed gas eliminates icing in the tunnel. Renting tanks eliminates storage concerns and the need for a compressor.

*Not to Scale

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Appendix B Appendix B Blowdown Tunnel Static Blowdown Tunnel Static

PressurePressure

Observations

•Atm. pressure in test section

120

2

11

ii

Mp

p 20

2

11 i

iM

T

T

Observations

•Reservoir Temp. is Room Temp.

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Appendix B Appendix B Blowdown Tunnel Throat AreaBlowdown Tunnel Throat Area

1/12

2

2

* 2

11

1

21

MMA

A

i

i

Observations

This is a unit depth Area, since at any point the nozzle is 0.25 inches deep.

Observations

•Nozzle Tolerance if Mach tolerance is ±0.05

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Appendix B Appendix B Blowdown Tunnel Mass FlowBlowdown Tunnel Mass Flow

Observations

Mass flow increases with Test Section Area and Mach Number

Observations

•At the nominal test section area

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Appendix CAppendix CVolumeflow ConversionVolumeflow Conversion

s

a

aatm

satmsa T

T

PP

PQQ

_

QQaa Volume Flow Rate at Actual ConditionsVolume Flow Rate at Actual Conditions

QQss Volume Flow Rate at Standard ConditionsVolume Flow Rate at Standard Conditions

PPatm_satm_s Standard Absolute Atmospheric PressureStandard Absolute Atmospheric Pressure

PPatmatm Actual Absolute Atmospheric PressureActual Absolute Atmospheric Pressure

PPaa Actual Gage PressureActual Gage Pressure

TTaa Actual Absolute TemperatureActual Absolute Temperature

TTss Standard Absolute TemperatureStandard Absolute Temperature

Ref [11]

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Appendix CAppendix CNo Settling TankNo Settling Tank

•Assumptions•Adiabatic, Polytropic, Expansion

•Tank specs•8.5” diameter•50” height•2000 psi

•Venting straight from tank through nozzle and test section

2211 VPVP

•Conclusions•12 tanks for 12 runs of 6 sec at Mach 2 •Higher Pressure

•Increased structure•More expensive valves and linkages

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•Assumptions•Adiabatic, Polytropic, Expansion

•Tank Specs•8.5” diameter•50” height•2000 psi

Appendix CAppendix CSettling Tank OptimizationSettling Tank Optimization

2211 VPVP

•Conclusions•Settling tank: 4 ft3 at 450 psi for Mach 2 •8 tanks required for 12 runs at Mach 2•Pressure increases to 1000 psi (still 4 ft3) for Mach 3

Contours: Number of Tanks for 12 runs at Mach 2

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Appendix DAppendix DNozzle Material Selection Nozzle Material Selection

Invar Titanium Beta III K-300 Nickel Alloy Grade 705 ZrThermal Expansion (um/mC) 1.3 7.6 6.8 6.3Specific Strength (Mpa/g/cc) 60 436.89 122.29 58.85Cost $/lb 215 150 67 80Hardness (vickers) 900 970 903 638

OptionsOptions• Matweb.comMatweb.com

– InvarInvar– Titanium Beta IIITitanium Beta III– K-300 NickelK-300 Nickel– Grade 705 ZirconiumGrade 705 Zirconium

Ref [7]

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Appendix DAppendix DTest Section Material SelectionTest Section Material Selection

OptionsOptions• PlexiglassPlexiglass• PolycarbonatePolycarbonate• GlassGlass

Plexiglass Polycarbonate GlassThermal Expansion (um/m-C) 67.4 69.5 25Thermal Conductivity (W/m-K) 0.17 0.2 1.17Refactive Index 1.48 1.59 1.54% Visible Allowed 91.7 88 87Specific Strength (Mpa/g/cc) 50 52.08 38.7Cost ($/lb)Hardness Rockwell M 79.2 75.7 205 (vickers)

Ref [7]

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Appendix EAppendix EPitot TubePitot Tube

• Replacement Mach number Replacement Mach number verificationverification

• Compressibility corrections requiredCompressibility corrections required– Factors are empiricalFactors are empirical

• Measurements made with Measurements made with transducers or manometertransducers or manometer

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Appendix EAppendix EPitot TubePitot Tube

Ref [10]

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Appendix FAppendix FVisualization ConsiderationsVisualization Considerations

Ref [14]Home

82

Appendix FAppendix FVisualization ConsiderationsVisualization Considerations

Ref [17]

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Appendix GAppendix GSingle Mirror SchlierenSingle Mirror Schlieren

“Well, for example, suppose you place a 2-D wedge in the test section of your wind tunnel. With parallel light and good alignment you will see the wedge in silhouette and sharp lines representing the oblique shocks it generates, since the planar shocks will be aligned with the optical beam direction. Not so if you use non-parallel light: then the shocks (and all other flow features) will have an apparent ‘thickness’; although they are extremely thin in nature. This is so misleading that essentially no one ever does this in M>1 wind tunnel practice.”

-Gary S. SettlesRef [13]

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Appendix HAppendix HRefraction DetectionRefraction Detection

Focal Length SensitivityFocal Length Sensitivity

Test

Section

Original Ray

Deflected Ray

Focal Length

•Short focal length decreases footprint•Long focal length increases tolerance

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Appendix HAppendix HRefraction DetectionRefraction Detection

Focal Length SensitivityFocal Length Sensitivity

•Contours: Amount of Refraction (in)

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Appendix IAppendix IMeasurement FeasibilityMeasurement Feasibility

• Thin boundary layerThin boundary layer• Worst case is ± .33 degreesWorst case is ± .33 degrees• High resolution camera is needed for High resolution camera is needed for

non-pixilated zoomsnon-pixilated zooms

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Appendix JAppendix JFuture ConsiderationFuture Consideration

NozzleNozzleObservations

•Interface to settling tank same as test cross-section

•1 inch by 0.25 inches

•Throat-area determined

•Depth 0.25 inches (2-D)

•Width determined by

•Connect the dots…

•Method known, but shape not yet determined

Key Variables

•Shape of sidewalls 1/1

22

2

* 2

11

1

21

MMA

A

i

i

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Nozzle Design MethodsNozzle Design Methods

1arctan11

1arctan

1

1

angleexpansion Meyer -Prandtl

22

MMv

Observations

• Three regions

1. Contraction

2. Sonic pre-inflection

3. Sonic post-inflection

11sin2

1tancot

angle deflection

angle shock wave

22

2

M

M

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Nozzle Design MethodsNozzle Design MethodsDesign Methods

•Busemann’s Method – Assume initial curve and adjust

•Puckett’s Method – Start at inflection point work both ways

•Foelch’s Method – Same as Puckett’s except analytic

Design Assumptions

•In-viscid Flow – No boundary layer effects, but…

•Eliminates Navir Stokes equations

•Fairly accurate, especially for short nozzles.

•Correction factors for boundary layer thickness

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