Development of a fast methane sensor based on wavelength modulation spectroscopy for exhaust methane emission measurement
department or school: Applied Science, Faculty of
department or school: Mechanical Engineering, Department of
data provider: DSpace
degree campus: UBCV
creator: Son, Donghyun (Jeff)
issued: 2019-10-21T16:55:17Z
issued: 2019
related degree: Master of Applied Science - MASc
degree grantor: University of British Columbia
description: Natural gas is an attractive alternative fuel with a lower price and carbon dioxide emission compared to liquid fossil fuels. Methane (CH₄) in natural gas, however, has a high global warming potential (GWP), thus the emission of unburnt CH₄ can offset the cleaner combustion of natural gas and should be carefully monitored in dual-fuel natural gas/diesel engines. To develop cleaner engines, a high-speed methane sensor in the exhaust gas stream is required to capture emissions during real-world, transient engine operation. While CH₄ measurements using Fourier-transform infrared (FTIR) spectroscopy in dual-fuel engines have been demonstrated, its speed is insufficient for cycle-resolved measurements. To this end, a fast, robust, and inexpensive CH₄ sensor based on wavelength modulation spectroscopy (WMS) was developed using a relatively inexpensive IR diode laser with a centre wavelength of 1651 nm. The WMS sensor was assessed using gas standards and validated against a flame ionization detector (FID). The 508 mm heated gas cell reliably detects CH₄ from 50 ppm to over 2% at a temporal resolution of over 200 Hz. The WMS sensor can resolve transient methane emission with a time delay and time constant of 0.55 s and 0.44 s respectively. When demonstrated on a heavy-duty dual-fuel research engine, the WMS sensor and FID agreed with a mean percentage difference of 4.2%. The field measurement capability of this portable sensor, which can continuously measure for seconds to hours, was demonstrated on dual-fuel marine engines of a coastal vessel. The GWP of dual-fuel engine exhaust heavily depends on operational profiles, and the fast WMS methane sensor will assist engineers and policy makers to characterize and reduce in-use CH₄ emissions.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/71999
note: DEVELOPMENT OF A FAST METHANE SENSOR BASED ONWAVELENGTH MODULATION SPECTROSCOPY FOR EXHAUSTMETHANE EMISSION MEASUREMENTbyDonghyun (Jeff) SonBASc, The University of British Columbia, 2016A THESIS SUBMITTED IN PARTIAL FULFILLMENT OFTHE REQUIREMENTS FOR THE DEGREE OFMASTER OF APPLIED SCIENCEinTHE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES(Mechanical Engineering)THE UNIVERSITY OF BRITISH COLUMBIA(Vancouver)October 2019c© Donghyun (Jeff) Son, 2019The following individuals certify that they have read, and recommend to the Faculty ofGraduate and Postdoctoral Studies for acceptance, the thesis entitled:Development of a fast methane sensor based on wavelength modulation spectroscopyfor exhaust methane emission measurementsubmitted by Donghyun (Jeff) Son in partial fulfillment of the requirements forthe degree of Master of Applied Sciencein Mechanical EngineeringExamining Committee:Patrick Kirchen, Mechanical EngineeringSupervisorSteven Rogak, Mechanical EngineeringSupervisory Committee MemberNaomi Zimmerman, Mechanical EngineeringAdditional ExamineriiAbstractNatural gas is an attractive alternative fuel with a lower price and carbon dioxide emis-sion compared to liquid fossil fuels. Methane (CH4) in natural gas, however, has a highglobal warming potential (GWP), thus the emission of unburnt CH4 can offset the cleanercombustion of natural gas and should be carefully monitored in dual-fuel natural gas/dieselengines. To develop cleaner engines, a high-speed methane sensor in the exhaust gas streamis required to capture emissions during real-world, transient engine operation. While CH4measurements using Fourier-transform infrared (FTIR) spectroscopy in dual-fuel engineshave been demonstrated, its speed is insufficient for cycle-resolved measurements. To thisend, a fast, robust, and inexpensive CH4 sensor based on wavelength modulation spec-troscopy (WMS) was developed using a relatively inexpensive IR diode laser with a centrewavelength of 1651 nm.The WMS sensor was assessed u…
has type: Thesis/Dissertation
date issued: 2019-11
is shown at: 10.14288/1.0384580
language: eng
degree discipline: Mechanical Engineering
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/71999