Temperature and multi-species measurements by supercontinuum absorption spectroscopy for IC engine applications

Area of Science:

• Spectroscopy
• Physical Chemistry
• Combustion Science

Background:

• Accurate temperature measurement is crucial for understanding combustion processes.
• Previous methods for in-situ temperature evaluation in engines have limitations.
• Supercontinuum (SC) spectroscopy offers a novel approach for rapid, quantitative measurements.

Purpose of the Study:

• To present the first supercontinuum absorption spectroscopy measurements for quantitative temperature evaluation.
• To demonstrate the feasibility of temperature and multi-species measurements in a high-temperature flow cell.
• To simulate conditions relevant to the suction and compression strokes of an internal combustion (IC) engine.

Main Methods:

• Utilized broadband supercontinuum pulses dispersed into fast wavelength sweeps.
• Covered overtone absorption bands of H2O and CO2 in the near-infrared (1330-1500 nm).
• Inferred temperature from the peak ratio of sensitive and insensitive absorption features of water.

Main Results:

• Achieved temperature measurements in a flow cell from 450 K to 750 K at 0.22 MPa.
• Demonstrated quantitative temperature evaluation with high detection rates (~2 MHz).
• Experimental results showed excellent agreement with theoretical calculations based on HiTran data.

Conclusions:

• Supercontinuum absorption spectroscopy is a feasible technique for quantitative temperature evaluation.
• The method is suitable for in-situ measurements under conditions mimicking IC engines.
• This technique holds promise for advanced combustion diagnostics and engine optimization.