Towards accurate measurement of methanol combustion emissions : Calibration and Insights for flame ionization detectors and Fourier transform infrared analyzers
(2025) In Fuel 395.- Abstract
Methanol is a promising renewable fuel that can be used to reduce the carbon intensity of internal combustion engines. In any combustion strategy with methanol, both unburned methanol and formaldehyde emissions are criteria pollutants that are potential drawbacks, so their accurate measurement is critical. The flame ionization detectors (FIDs) typically used in engine research to measure unburned hydrocarbons show a reduced sensitivity to oxygenated species like methanol and formaldehyde. A correction factor can be applied to the FID, but the value used for methanol combustion varies in the literature. Fourier transform infrared (FTIR) detectors can measure speciated organic species, such as methanol and formaldehyde, but commonly used... (More)
Methanol is a promising renewable fuel that can be used to reduce the carbon intensity of internal combustion engines. In any combustion strategy with methanol, both unburned methanol and formaldehyde emissions are criteria pollutants that are potential drawbacks, so their accurate measurement is critical. The flame ionization detectors (FIDs) typically used in engine research to measure unburned hydrocarbons show a reduced sensitivity to oxygenated species like methanol and formaldehyde. A correction factor can be applied to the FID, but the value used for methanol combustion varies in the literature. Fourier transform infrared (FTIR) detectors can measure speciated organic species, such as methanol and formaldehyde, but commonly used commercial FTIR software may not be calibrated to high enough levels of engine-out methanol to properly compare methanol combustion strategies. The primary focus of this work is to describe a methodology to generate calibration data for the FID and FTIR using a typical single cylinder research engine test stand. This work also aims to emphasize the measurement mechanisms of these devices to avoid their misuse, specifically for methanol combustion and more generally for renewable fuels research. The methanol FID response factor variance in the literature is because methanol, formaldehyde, and other incomplete combustion products from methanol combustion have different FID sensitivities. Using calibration data generated in this work, the FID response factor for pure methanol was determined to be ∼0.75 and an FTIR correction curve for Beer-Lambert's law deviations for methanol up to ∼5000 ppm was generated along with accessible calibration spectra. The aggregate FID sensitivity varies with operating strategy depending on the exhaust speciation. This work demonstrates this explicitly with data containing methanol and formaldehyde in a 10:1 ratio showing a FID response factor of ∼0.68. Thus, further work is motivated to generate comprehensive datasets of different methanol combustion strategies to improve the selection of FID response factor for methanol combustion research.
(Less)
- author
- Gainey, Brian LU and Tunér, Martin LU
- organization
- publishing date
- 2025-09
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Flame Ionization Detector, Fourier Transform Infrared Detector, Methanol
- in
- Fuel
- volume
- 395
- article number
- 135149
- publisher
- Elsevier
- external identifiers
-
- scopus:105001408938
- ISSN
- 0016-2361
- DOI
- 10.1016/j.fuel.2025.135149
- language
- English
- LU publication?
- yes
- id
- cb492019-d497-48a1-91d6-cf9518548719
- date added to LUP
- 2025-08-06 11:24:39
- date last changed
- 2025-08-06 11:24:59
@article{cb492019-d497-48a1-91d6-cf9518548719,
abstract = {{<p>Methanol is a promising renewable fuel that can be used to reduce the carbon intensity of internal combustion engines. In any combustion strategy with methanol, both unburned methanol and formaldehyde emissions are criteria pollutants that are potential drawbacks, so their accurate measurement is critical. The flame ionization detectors (FIDs) typically used in engine research to measure unburned hydrocarbons show a reduced sensitivity to oxygenated species like methanol and formaldehyde. A correction factor can be applied to the FID, but the value used for methanol combustion varies in the literature. Fourier transform infrared (FTIR) detectors can measure speciated organic species, such as methanol and formaldehyde, but commonly used commercial FTIR software may not be calibrated to high enough levels of engine-out methanol to properly compare methanol combustion strategies. The primary focus of this work is to describe a methodology to generate calibration data for the FID and FTIR using a typical single cylinder research engine test stand. This work also aims to emphasize the measurement mechanisms of these devices to avoid their misuse, specifically for methanol combustion and more generally for renewable fuels research. The methanol FID response factor variance in the literature is because methanol, formaldehyde, and other incomplete combustion products from methanol combustion have different FID sensitivities. Using calibration data generated in this work, the FID response factor for pure methanol was determined to be ∼0.75 and an FTIR correction curve for Beer-Lambert's law deviations for methanol up to ∼5000 ppm was generated along with accessible calibration spectra. The aggregate FID sensitivity varies with operating strategy depending on the exhaust speciation. This work demonstrates this explicitly with data containing methanol and formaldehyde in a 10:1 ratio showing a FID response factor of ∼0.68. Thus, further work is motivated to generate comprehensive datasets of different methanol combustion strategies to improve the selection of FID response factor for methanol combustion research.</p>}},
author = {{Gainey, Brian and Tunér, Martin}},
issn = {{0016-2361}},
keywords = {{Flame Ionization Detector; Fourier Transform Infrared Detector; Methanol}},
language = {{eng}},
publisher = {{Elsevier}},
series = {{Fuel}},
title = {{Towards accurate measurement of methanol combustion emissions : Calibration and Insights for flame ionization detectors and Fourier transform infrared analyzers}},
url = {{http://dx.doi.org/10.1016/j.fuel.2025.135149}},
doi = {{10.1016/j.fuel.2025.135149}},
volume = {{395}},
year = {{2025}},
}