Fiber Optics and Fiber Optics and Atmospheric MonitoringAtmospheric Monitoring

Matthew J. ParkerMatthew J. ParkerSavannah River Technology CenterSavannah River Technology Center

Westinghouse Savannah River CompanyWestinghouse Savannah River Company

Aiken, South CarolinaAiken, South Carolina

andand

Carvel E. HoltonCarvel E. HoltonVirginia Polytechnic and State UniversityVirginia Polytechnic and State University

Blacksburg, VirginiaBlacksburg, Virginia

OutlineOutline

BackgroundBackground

SensorsSensors

Design applicationsDesign applications

- Industrial- Industrial

- Atmospheric turbulence- Atmospheric turbulence

System IntegrationSystem Integration

Cost-Effectiveness/Potential ImprovementsCost-Effectiveness/Potential Improvements

UPDATEUPDATE

BackgroundBackground

Optical technology benefitsOptical technology benefits--

- - No RFI/lightningNo RFI/lightning

Environmental Sensors-Environmental Sensors-- - Met and air pollutionMet and air pollution

Developments in Communications IndustryDevelopments in Communications Industry--

- - BenefitsBenefits

Combine optical sensorsCombine optical sensors--

- - Complete systemComplete system (ref. Holton and Parker, 1999 SPIE)(ref. Holton and Parker, 1999 SPIE)

SensorsSensors

• • Conventional cup and vaneConventional cup and vane

• • Fiber lidarFiber lidar

• • Temperature/Temperature/TT

• • Relative humidityRelative humidity

• • Barometric pressureBarometric pressure

• • VisibilityVisibility

• • Total precipitationTotal precipitation

• • Chemical/particulate/hazards/electro-Chemical/particulate/hazards/electro-magnetic/ corrosion/spectra/etc.magnetic/ corrosion/spectra/etc.

Design ApplicationsDesign Applications

Industrial ApplicationIndustrial Application

-- Routine monitoring-- Routine monitoring

-- Meteorological-- Meteorological

-- Air quality-- Air quality

Atmospheric Turbulence Atmospheric Turbulence

-- Research/Experiments-- Research/Experiments

Industrial Monitoring SystemIndustrial Monitoring System

1

2

3

4

1. Tower based measurements:wind vanecup anemometertemperature/Trelative humiditypressure

2. Field measurement:rain gauge

3. Remote sensor:doppler lidar

4. Fenceline measurement:particle counter

5. Data acquisition (protected)

5

Atmospheric TurbulenceAtmospheric Turbulence

VariableVariable Sensor / Response TimeSensor / Response Time

Wind speedWind speed Fiber lidar / 0.001s (OSA, 1995)Fiber lidar / 0.001s (OSA, 1995)

Wind directionWind direction Fiber lidar / 0.001s (OSA, 1995)Fiber lidar / 0.001s (OSA, 1995)

TemperatureTemperature Bragg-grating / 0.01s (Bhatia, et. al, 1996 and Kersey, Bragg-grating / 0.01s (Bhatia, et. al, 1996 and Kersey, 1995) 1995)

RelativeRelative Coated fiber / 0.1s (Arregui, et al, 1999)Coated fiber / 0.1s (Arregui, et al, 1999)

humidityhumidity

BarometricBarometric diaphragm / 0.01s (Xiao, et. al, 1995)diaphragm / 0.01s (Xiao, et. al, 1995)pressurepressure

System IntegrationSystem Integration

Multiplexed optical signalsMultiplexed optical signals

over single (or limited) fibersover single (or limited) fibers

Connectors used for quick sensor Connectors used for quick sensor change-outchange-out

Cost-Effectiveness and Cost-Effectiveness and Potential ImprovementsPotential Improvements

Fiber optic components developed for Fiber optic components developed for telecommunications industrytelecommunications industry

Fiber sensors less prone to wear (non-Fiber sensors less prone to wear (non-mechanical)mechanical)

Costs driven lower with inexpensive Costs driven lower with inexpensive sensorssensors

CONCLUSIONCONCLUSION

An optical atmospheric An optical atmospheric monitoring system can monitoring system can become a reality with become a reality with

today’s technology! . . .today’s technology! . . .

UPDATE!!!UPDATE!!!

SBIR Phase IISBIR Phase II between VaTech and between VaTech and

Yankee Environmental SystemsYankee Environmental Systems

PRODUCTS: Fiber Lidar & RH SensorPRODUCTS: Fiber Lidar & RH Sensor

1 4 7

10 13

16

19

22

25S

1 S5 S

9 S1

3 S1

7 S2

1 S2

5 S2

9 S3

3

-0.01

-0.005

0

0.005

0.01

0.015

0.02

0.025

0.03

Tim e, m inutes

Signal Intensity

Time Evolution of Small Agricultural Fire3/26/02

0.025-0.03

0.02-0.025

0.015-0.02

0.01-0.015

0.005-0.01

0-0.005

-0.005-0

-0.01--0.005

Range, ft

1800ft

2400ft

Fire Center at a range of 2160ft

Fiber Lidar Data--SmokeFiber Lidar Data--Smoke

Fiber Lidar Data--CloudsFiber Lidar Data--Clouds

Cloud Lidar Path Comparison, 3/19/02

-0.2455

-0.245

-0.2445

-0.244

-0.2435

-0.243

-0.2425

0 500 1000 1500 2000 2500 3000 3500

Range, ft

Sig

nal

Am

plit

ud

e, v

olts

Vertical Path

Horizontal Path

Cloud Layer

Fiber RH SensorFiber RH Sensor

Optical Fiber Humidity Sensor Response to Breathing

0.08

0.085

0.09

0.095

0.1

0.105

0.11

0.115

0.12

0.125

0.13

0 5 10 15 20 25 30 35

Time, s

Rel

ativ

e A

mplit

ude