Characterization of the Transient Response of a Diesel Exhaust-Gas Measurement System

McClure, B. T.

doi:10.4271/881320

Cited by 16 publications

(3 citation statements)

References 3 publications

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“…Unsurprisingly, alternative modeling approaches have been proposed for predicting diesel engine transient emissions, e.g. based on steadystate mapping and applying correction factors to account for transient discrepancies [23,24]; on the other hand, reconstruction techniques of the measured signal using conventional slow response analyzers have been deployed, either by mathematical signal processing [25,26] or by modeling the gas flow into the analyzer [27].…”

Section: Introductionmentioning

confidence: 99%

Experimental Assessment of Turbocharged Diesel Engine Transient Emissions during Acceleration, Load Change and Starting

Rakopoulos

Dimaratos

Giakoumis

et al. 2010

SAE Technical Paper Series

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The control of transient emissions from turbocharged diesel engines remains an important objective to manufacturers, since newly produced engines must meet the stringent criteria concerning exhaust emissions levels as dictated by the legislated Transient Cycles. In the present work, experimental tests are conducted on a medium-duty, turbocharged and after-cooled diesel engine in order to investigate the behavior and formation mechanism of nitric oxide (NO), smoke and combustion noise emissions under various transient operating schedules including acceleration, load change and starting. To this aim, a fully instrumented test bed was set up in order to record and research key engine and turbocharger variables during the transient events. The main parameters measured are nitric oxide concentration and smoke opacity (both using ultra-fast response analyzers) as well as combustion noise. Various other variables were monitored, such as in-cylinder pressure, engine speed, fuel pump rack position, boost pressure and turbocharger speed. The main focus of the experimental investigation was devoted to engine acceleration tests representative of automotive and truck applications, commencing from various engine speeds and loads. The experimental test pattern also included load increases and (cold and hot) startings. Analytical diagrams are provided to explain the behavior of exhaust emissions development in conjunction with turbocharger and governor/fuel pump response. Turbocharger lag was found to be the main cause for the emissions peak values observed during all transient events. During starting, the lack of air and its mismatch with fueling caused excessive black smoke, identified by the extremely high values of exhaust gas opacity.

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Section: Introductionmentioning

confidence: 99%

Experimental Assessment of Turbocharged Diesel Engine Transient Emissions during Acceleration, Load Change and Starting

Rakopoulos

Dimaratos

Giakoumis

et al. 2010

SAE Technical Paper Series

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show abstract

“…Often, due to budgetary constraints, research centres and institutions prefer to measure the transient emission signals using slow-response analysers but with signal corrections. This signal-correction concept was first proposed by McClure [4], who conducted research with the intention of reducing the exposure of miners to the exhaust emissions of dieselpowered underground equipment. By generating some known-concentration emission pulses and measuring the responses at the analyser output, he characterized the analyser by formulating a transfer function which he later used to infer the variations of concentration in the exhaust gases.…”

Section: Introductionmentioning

confidence: 99%

An innovative carbon-atom-balance-based method for diesel particulate measurement

Chan¹,

He²,

Ge³

1999

Meas. Sci. Technol.

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This paper describes an innovative carbon-atom-balance-based method for diesel particulate measurement using a single non-dispersive infrared CO2 sensor. The diesel particulate sampler (DPS) uses two integrated steps of operation, i.e. collection and analysis of diesel particulate. In the collection operation, the diesel exhaust is channelled through a heated sampling line to a quartz filter where soot particulates, unburned hydrocarbons, water vapour, etc are trapped. Upon completion of particulate collection, the DPS system is isolated from the surroundings. This is followed by an analysis of the diesel-particulate sample by either one of two analysis modes, namely, the regular and ramp modes. In the regular mode, the quartz filter is heated at a constant temperature for a defined dwelling period. Multiple sessions of heating at constant temperatures with individual dwelling periods are allowed for each analysis. In the ramp mode, the temperature controller is programmed to achieve a specified heating rate. The lowest possible rate is 2 °C min-1. Some preliminary results, in terms of mass concentrations of particulates, were obtained from engine emission sampling using this DPS system.

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“…This method, known as 'signal inference' or 'signal reconstruction', is a technique that acquires distorted emission signals from slow-response analysers during transient engine operation and then restores the signal by analytical means. It was first proposed by McClure [8], who conducted research to reduce the exposure of miners to exhaust emissions of diesel-powered underground equipment. By generating some known concentration emission pulses and measuring the response at the analyser output, he characterized the analyser by formulating a transfer function which he later used to infer the variation of concentration in the exhaust gases.…”

Section: Introductionmentioning

confidence: 99%

Study on the Electrical Conduction Mechanism in Al₂O₃/Polyimide Langmuir-Blodgett Film Systems

Kushida¹,

Iwamoto

Hino

1993

Jpn. J. Appl. Phys.

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Conventional multi-gas emission analysers based upon the non-dispersive infrared measuring technique are of limited use in transient engine testing as the dynamic response of these analysers causes distortion of the emission signal measured during transient engine operation. This problem is magnified when filters are installed upstream of the analysers for the removal of solid carbon present in diesel exhausts. The capacitive/damping effect of these filters makes the measurement of the concentrations of transient gases unreliable. A combined experimental and phenomenological model is hence proposed which simulates the behaviour of gas transport through an emission analyser by a series of alternately arranged pipes and surge volumes such that the distortion of the emission signal can be physically explained and modelled. Characterization of the emission analyser by means of two physical models, namely diffusion and perfect gas-mixing models, is adopted as the basis for analysis, so that physical interpretation can be made to account for the resulting distortion and variation of the measured emission signal. The actual emission signal before being distorted by the slow-response emission analyser can be inferred by solving these models numerically. A computer program has been developed which provides a continuous signal inference from a series of distorted emission pulses measured during transient engine operation.

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Characterization of the Transient Response of a Diesel Exhaust-Gas Measurement System

Cited by 16 publications

References 3 publications

Experimental Assessment of Turbocharged Diesel Engine Transient Emissions during Acceleration, Load Change and Starting

Experimental Assessment of Turbocharged Diesel Engine Transient Emissions during Acceleration, Load Change and Starting

An innovative carbon-atom-balance-based method for diesel particulate measurement

Study on the Electrical Conduction Mechanism in Al₂O₃/Polyimide Langmuir-Blodgett Film Systems

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Characterization of the Transient Response of a Diesel Exhaust-Gas Measurement System

Cited by 16 publications

References 3 publications

Experimental Assessment of Turbocharged Diesel Engine Transient Emissions during Acceleration, Load Change and Starting

Experimental Assessment of Turbocharged Diesel Engine Transient Emissions during Acceleration, Load Change and Starting

An innovative carbon-atom-balance-based method for diesel particulate measurement

Study on the Electrical Conduction Mechanism in Al2O3/Polyimide Langmuir-Blodgett Film Systems

Contact Info

Product

Resources

About

Study on the Electrical Conduction Mechanism in Al₂O₃/Polyimide Langmuir-Blodgett Film Systems