MOEMS SPECTROMETER:

IQF SensorIntegrated Fuel Quality Sensor – EUR 07-408

INTRODUCTION:"IQF sensor project" is devoted to development of one automotive embedded sensor (MOEMS based) for real time measurement of used fuel composition together with related engine and exhaust gas aftertreatment control function. Fuel type can be either diesel or gasoline.

The sensor is using Near Infrared Absorption spectroscopy together with mathematical model (chemiometry) to predict the fuel parameters relevant for engine combustion and exhaust gas aftertreatment efficiency. The spectrometer and detection units are based on 2 MOEMS components integrated within one single package.

SENSING PRINCIPLE:

IR broad band sourceFUELFUEL

Moems

V

Wavelenght

Infrared Absoprtion Spectrum

Spacer

Tunable filter(Interferometer)

13 … 20 mm

Broadband IR Detector

(Thermopile)

Interferometer chip:

• silicon based

• dielectric mirrors (Al203 – TiO2)

Thermopile chip:

• thermocouple array

• absorber material (Al203 film)

Fuel out

4400 4600 4800 5000 5200 5400 5600 5800 6000 6200-1

0

1

2

3

4

5

6

7x 10

-3

Wavenumbers (cm-1)

Abs

orba

nce

SpectraFuel spectrumdatabase

Chemiometricsmodel

Spectrum acquisition

Fuel parameter prediction:

cetane #

bio %

heating value

water content

.....

Fuel parameter prediction:

cetane #

bio %

heating value

water content

.....

Dataprocessing

Dataprocessing

Fuel in

TARGET SPECIFICATION:

SENSOR DESIGN:

Light source

Electronic unitHousing

MOEMS

Cover

Cover

Glass window

Fuel line

Biodiesel ConcentrationBiodiesel Concentration

DensityDensity

Cetane NumberCetaneNumber

Heating ValueHeating Value

Sulphur ContentSulphur Content

0-100% vol ± 5 %0-100% vol ±5 %

700 –900 kg/m³ ± 5 kg/m³700 – 900 kg/m³ ±5 kg/m³

40 – 70 ± 440 – 70 ±4

Depends on bio ± 2%

concentration

Depends on bio ±2%

concentration

classification high/low Threshold = 500ppm

content

classification high/low Threshold = 500ppm

content

Measurement Range AccuracyMeasurement Range Accuracy

Ethanol ConcentrationEthanol Concentration 0-100% vol ± 5 %0-100% vol ± 5 %

Octane indexOctane index 80-100 ± 280-100 ±2

Reid vapor pressureReid vapor pressure 350-1100 hPa ± 35 hPa350-1100 hPa ±35 hPa

Measurement location: in fuel line

Pressure Range: <10bar

Temperature range: -40°C to +85°C

Sensor Signal: CAN, SENT

No field calibration

PROJECT DATA:Starting: April 2008 SP1: specification/added value - completedClosure: October 2011 SP2/SP3: sensor/MOEMS design – 50%Budget: 8.1 Meuros SP4: engine control function – 10%Man Power: 519 MenMonths SP5: test/validation – 0%

BENEFITS:• Optimization of engine and after treatment units efficiency (DPF, SCR, CO): reduction of C02, NOx, particle emission and fuel economy• Improvement of drivability (e.g.: engine knocking, cold start)• Engine component reliability improvment• Same concept can be used for Oil and AdBlue diagnostic

LAB RESULTS:

•from A2 samples• good linearity• good repeatability

TCF022 + Ethanol absorbance spectrums

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

1509 1609 1709 1809 1909 2009Wavelength [nm]

100% EthanolTCF022 + 20% EthanolTCF022 + 40% EthanolTCF022 + 60% EthanolTCF022 + 80% EthanolTCF022 + 0% EthanolTCF022 + 33% EthanolTCF022 + 66% Ethanol

A2 sample