Assessment of Residual Mass Estimation Methods for Cylinder Pressure Heat Release Analysis of HCCI Engines with Negative Valve Overlap

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21220%2F11%3A00229500" target="_blank" >RIV/68407700:21220/11:00229500 - isvavai.cz</a>

Výsledek na webu

<a href="http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1627311&resultClick=1" target="_blank" >http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1627311&resultClick=1</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1115/ICEF2011-60167" target="_blank" >10.1115/ICEF2011-60167</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Assessment of Residual Mass Estimation Methods for Cylinder Pressure Heat Release Analysis of HCCI Engines with Negative Valve Overlap

Popis výsledku v původním jazyce

Increased residual levels in Homogeneous Charge Compression Ignition (HCCI) engines employing valve strategies such as recompression or negative valve overlap (NVO) imply that accurate estimation of residual gas fraction (RGF) is critical for cylinder pressure heat release analysis. The objective of the present work was to evaluate three residual estimation methods and assess their suitability under naturally aspirated and boosted HCCI operating conditions: i) the Simple State Equation method employs the Ideal Gas Law at exhaust valve closing (EVC); ii) the Mirsky method assumes isentropic exhaust process; and iii) the Fitzgerald method models in-cylinder temperature from exhaust valve opening (EVO) to EVC by accounting for heat loss during the exhaust process and uses measured exhaust temperature for calibration. Simulations with a calibrated and validated "virtual engine" were performed for representative HCCI operating conditions of engine speed, fuel-air equivalence ratio, NVO and intake pressure (boosting). The State Equation method always overestimated RGF by more than 10%. The Mirsky method was most robust, with average errors between 3-5%. The Fitzgerald method performed consistently better, ranging from no error to 5%, where increased boosting caused the largest discrepancies. A sensitivity study was also performed and determined that the Mirsky method was most robust to possible pressure and temperature measurement errors.

Název v anglickém jazyce

Assessment of Residual Mass Estimation Methods for Cylinder Pressure Heat Release Analysis of HCCI Engines with Negative Valve Overlap

Popis výsledku anglicky

Increased residual levels in Homogeneous Charge Compression Ignition (HCCI) engines employing valve strategies such as recompression or negative valve overlap (NVO) imply that accurate estimation of residual gas fraction (RGF) is critical for cylinder pressure heat release analysis. The objective of the present work was to evaluate three residual estimation methods and assess their suitability under naturally aspirated and boosted HCCI operating conditions: i) the Simple State Equation method employs the Ideal Gas Law at exhaust valve closing (EVC); ii) the Mirsky method assumes isentropic exhaust process; and iii) the Fitzgerald method models in-cylinder temperature from exhaust valve opening (EVO) to EVC by accounting for heat loss during the exhaust process and uses measured exhaust temperature for calibration. Simulations with a calibrated and validated "virtual engine" were performed for representative HCCI operating conditions of engine speed, fuel-air equivalence ratio, NVO and intake pressure (boosting). The State Equation method always overestimated RGF by more than 10%. The Mirsky method was most robust, with average errors between 3-5%. The Fitzgerald method performed consistently better, ranging from no error to 5%, where increased boosting caused the largest discrepancies. A sensitivity study was also performed and determined that the Mirsky method was most robust to possible pressure and temperature measurement errors.

Druh

D - Stať ve sborníku

CEP obor

JT - Pohon, motory a paliva

OECD FORD obor

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Projekt

<a href="/cs/project/ED2.1.00%2F03.0125" target="_blank" >ED2.1.00/03.0125: Pořízení technologie pro Centrum vozidel udržitelné mobility</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2011

Kód důvěrnosti údajů

C - Předmět řešení projektu podléhá obchodnímu tajemství (§ 504 Občanského zákoníku), ale název projektu, cíle projektu a u ukončeného nebo zastaveného projektu zhodnocení výsledku řešení projektu (údaje P03, P04, P15, P19, P29, PN8) dodané do CEP, jsou upraveny tak, aby byly zveřejnitelné.

Název statě ve sborníku

Proceedings of the ASME 2011 Internal Combustion Engine Division Fall Technical Conference

ISBN

978-0-7918-4442-7

ISSN

1066-5048

e-ISSN

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Počet stran výsledku

10

Strana od-do

481-490

Název nakladatele

American Society of Mechanical Engineers - ASME

Místo vydání

New York

Místo konání akce

Morgantown

Datum konání akce

2. 10. 2011

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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