HCCI Combustion of Hydrogen, Carbon Monoxide and Dimethyl Ether

Shudo, Toshio

doi:10.4271/2002-01-0112

Cited by 47 publications

(24 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As extensively documented by previous work, hydrogen or gas mixtures containing hydrogen, such as methanol reformed gas and hydrogen rich gas, have proved to be an excellent additive to control the knock, extend the lean limit, the tolerance to EGR and improve engine variability in SI engines [15,35,39]. When added to HCCI fuels with low octane number such as DME, hydrogen addition has been shown to act as a rather effective means by which it is possible to control the start of combustion by affecting the low temperature oxidation process [72][73][74][75]. Specifically, on a fixed amount of DME, addition of hydrogen seemed to slow down and in some cases suppress the first heat release stage (without changing its phasing though) by converting the more reactive OH radicals into HO 2 and H 2 O 2 [75].…”

Section: Homogenous Charge Compression Ignition Thermodynamic Datamentioning

confidence: 99%

“…from a reformer or in combination with DiMethyl-Ether (DME). In such studies, better control of the timing of autoignition and improved thermal efficiency have been reported [72][73][74][75]. Yap et al [76] studied hydrogen addition to a natural-gas HCCI engine using modelling and experiments and found a reduction in the intake temperature required for HCCI operation, presumably due to the higher diffusivity and better mixing of hydrogen with air.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Hydrogen SI and HCCI Combustion in a Direct-Injection Optical Engine

Rosati¹,

Aleiferis²

2009

SAE Int. J. Engines

View full text Add to dashboard Cite

The Engineering Meetings Board has approved this paper for publication. It has successfully completed SAE's peer review process under the supervision of the session organizer. This process requires a minimum of three (3) reviews by industry experts. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. ISSN 0148-7191 Positions and opinions advanced in this paper are those of the author(s) and not necessarily those of SAE. The author is solely responsible for the content of the paper. SAE ABSTRACTHydrogen has been largely proposed as a possible alternative fuel for internal combustion engines. Its wide flammability range allows higher engine efficiency with leaner operation than conventional fuels, for both reduced toxic emissions and no CO 2 gases. Independently, Homogenous Charge Compression Ignition (HCCI) also allows higher thermal efficiency and lower fuel consumption with reduced NO X emissions when compared to Spark-Ignition (SI) engine operation. For HCCI combustion, a mixture of air and fuel is supplied to the cylinder and autoignition occurs from compression; engine is operated throttle-less and load is controlled by the quality of the mixture, avoiding the large fluid-dynamic losses in the intake manifold of SI engines. HCCI can be induced and controlled by varying the mixture temperature, either by Exhaust Gas Recirculation (EGR) or intake air pre-heating. A combination of HCCI combustion with hydrogen fuelling has great potential for virtually zero CO 2 and NO X emissions. Nevertheless, combustion on such a fast burning fuel with wide flammability limits and high octane number implies many disadvantages, such as control of backfiring and speed of autoignition and there is almost no literature on the subject, particularly in optical engines. Experiments were conducted in a singlecylinder research engine equipped with both Port Fuel Injection (PFI) and Direct Injection (DI) systems running at 1000 RPM. Optical access to in-cylinder phenomena was enabled through an extended piston and optical crown. Combustion images were acquired by a highspeed camera at 1° or 2° crank angle resolution for a series of engine cycles. Spark-ignition tests were initially carried out to benchmark the operation of the engine with hydrogen against gasoline. DI of hydrogen after intake valve closure was found to be preferable in order to overcome problems related to backfiring and air displacement from hydrogen's low density. HCCI combustion of hydrogen was initially enabled by means of a pilot port injection of n-heptane preceding the main direct injection of hydrogen, along with intake air preheating. Sole hydrogen fuelling HCCI was finally achieved and made sustainable, even at the low compression ratio of the optical engine by means of closed-valve DI, in synergy with air-pre-heating and negative valve overlap to promote intern...

show abstract

Section: Homogenous Charge Compression Ignition Thermodynamic Datamentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Hydrogen SI and HCCI Combustion in a Direct-Injection Optical Engine

Rosati¹,

Aleiferis²

2009

SAE Int. J. Engines

View full text Add to dashboard Cite

show abstract

“…With this background, an HCCI combustion engine system fuelled with DME and MRG has been proposed in a report [9]. The large reactivity difference of the two fuels enables an effective control of the ignition timing by adjusting the proportions of the two in the system.…”

Section: Introductionmentioning

confidence: 99%

Influence of gas composition on the combustion and efficiency of a homogeneous charge compression ignition engine system fuelled with methanol reformed gases

Shudo

2008

International Journal of Engine Research

View full text Add to dashboard Cite

A homogeneous charge compression ignition (HCCI) engine system fuelled with dimethyl ether (DME) and methanol-reformed gas (MRG), both produced from methanol by onboard reformers using exhaust heat, has been proposed in previous research. Adjusting the proportions of DME and MRG with different ignition properties effectively controlled the ignition timing and load in HCCI combustion. The use of the single liquid fuel, methanol, also eliminates the inconvenience of carrying two fuels while maintaining the effective ignition control effect. Because reactions producing DME and MRG from methanol are endothermic, a part of the exhaust gas heat energy can be recovered during the fuel reforming. Methanol can be reformed into various compositions of hydrogen, carbon monoxide, and carbon dioxide. The present paper aims to establish the optimum MRG composition for the system in terms of ignition control and overall efficiency. The results show that an increased hydrogen fraction in MRG retards the onset of high-temperature oxidation and permits operation with higher equivalence ratios. However, the MRG composition affects the engine efficiency only a little, and the MRG produced by the thermal decomposition having the best waste-heat recovery capacity brings the highest overall thermal efficiency in the HCCI engine system fuelled with DME and MRG.

show abstract

“…In a previous study [11], HCCI combustion of pure hydrogen was investigated and recent studies of RMG as engine fuel have been made by Shudo et al [2,12,13]. They performed SI engine tests with RMG mixtures and they also studied RMG-DME mixtures in combination with the new engine concept, HCCI, but no previous experimental study has focused on HCCI combustion of RMG only.…”

Section: Introductionmentioning

confidence: 99%

Reformed Methanol Gas as Homogeneous Charge Compression Ignition Engine Fuel

Stenlåås¹,

Christensen²,

Egnell³

et al. 2004

SAE Technical Paper Series

View full text Add to dashboard Cite

Hydrogen has been proposed as a possible fuel for automotive applications. Methanol is one of the most efficient ways to store and handle hydrogen. By catalytic reformation it is possible to convert methanol into hydrogen and carbon monoxide. This paper reports an experimental investigation of Reformed Methanol Gas as Homogeneous Charge Compression Ignition (HCCI) engine fuel. The aim of the experimental study is to investigate the possibility to run an HCCI engine on a mixture of hydrogen and carbon monoxide, to study the combustion phasing, the efficiency and the formation of emissions.Reformed Methanol Gas (RMG) was found to be a possible fuel for an HCCI engine. The heat release rate was lower than with pure hydrogen but still high compared to other fuels. The interval of possible start of combustion crank angles was found to be narrow but wider than for hydrogen. The high rate of heat release limited the operating range to lean (λ>3) cases as with hydrogen. On the other hand, operation on extremely lean mixtures (λ=6) was possible. The operating range was investigated using intake air temperature for control and also this control interval was found to be narrow but more extensive than for pure hydrogen, especially when richer cases were run. The maximal load in HCCI mode was a net Indicated Mean Effective Pressure (IMEPn) of 3.5 bar for RMG. This is the same maximum IMEPn as for hydrogen. It is about half the load possible in Spark Ignition (SI) mode and about half the maximal load in HCCI mode with other fuels. For the loads where HCCI operation was possible, indicated thermal efficiency for HCCI was superior to that of SI operation. The indicated overall efficiency of the engine-reformer system is as high for SI as for HCCI operation when RMG is used as fuel. NOx emissions were, as expected, found to decrease when the equivalence ratio was lowered. High levels of carbon monoxide were found in the exhaust. Emissions of hydrocarbons were detected, probably originating from evaporated and partially oxidized lubrication oil.

show abstract

HCCI Combustion of Hydrogen, Carbon Monoxide and Dimethyl Ether

Cited by 47 publications

References 12 publications

Hydrogen SI and HCCI Combustion in a Direct-Injection Optical Engine

Hydrogen SI and HCCI Combustion in a Direct-Injection Optical Engine

Influence of gas composition on the combustion and efficiency of a homogeneous charge compression ignition engine system fuelled with methanol reformed gases

Reformed Methanol Gas as Homogeneous Charge Compression Ignition Engine Fuel

Contact Info

Product

Resources

About