scholarly journals A thermo-kinetic model base study on natural gas HCCI engine response to different initial conditions

2009 ◽  
Vol 136 (1) ◽  
pp. 90-99
Author(s):  
Seyed JAZAYERI ◽  
Jahanian OMID
Keyword(s):  
Natural Gas ◽  
Initial Conditions ◽  
Chemical Species ◽  
Engine Performance ◽  
Zone Model ◽  
Model Base ◽  
Hcci Engine ◽  
Hcci Combustion ◽  
Base Study ◽  
Homogenous Charge Compression Ignition

Homogenous Charge Compression Ignition (HCCI) combustion is a promising concept to reduce engine emmisions and fuel consumption. In this paper, a thermo-kinetic single zone model is developed to study the operation characteristics of a natural gas HCCI engine. The model consists detail chemical kinetics of natural gas oxidation including 325 reactions with 53 chemical species, and is validated with experimental results of reference works. Then, the influence of parameters such as manifold temperature/pressure, and equivalance ratio on incylinder temperature/pressure trends, start of combustion and heat release rate is studied. These results are explained in detail to describe the engine performance thoroughly.

A Comprehensive Study on Natural Gas HCCI Engine Response to Different Initial Conditions via a Thermo-Kinetic Engine Model

2009 ◽  
Author(s):  
Omid Jahanian ◽  
Seyed Ali Jazayeri
Keyword(s):  
Natural Gas ◽  
Initial Conditions ◽  
Chemical Species ◽  
Engine Performance ◽  
Operating Conditions ◽  
Zone Model ◽  
Operating Characteristics ◽  
Hcci Engine ◽  
Engine Model ◽  
Homogenous Charge Compression Ignition

Homogenous Charge Compression Ignition (HCCI) combustion is a promising concept to reduce engine emissions and fuel consumption. In this paper, a thermo-kinetic model is developed to study the operating characteristics of a natural gas HCCI engine. The zero-dimensional single zone model consist detail chemical kinetics of natural gas oxidation including 325 reactions with 53 chemical species, and is validated with experimental results of reference works for two different engines, Volvo TD 100 and Caterpillar 3500, in 5 operating conditions. Then, the influence of parameters such as manifold temperature/pressure and equivalence ratio on in-cylinder temperature/pressure trends and start of combustion is studied. Measurements for Volvo engine show that SOC occurs 3–5 CAD earlier with every 15K increase in initial temperature. These whole results are explained in detail to describe the engine performance thoroughly.

scholarly journals Simulation of predictive kinetic combustion of single cylinder HCCI engine

2020 ◽  
Author(s):  
Ibham Veza ◽  
Mohd Farid Muhamad Said ◽  
Zulkarnain Abdul Latiff ◽  
Mohd Faizal Hasan ◽  
Rifqi Irzuan Abdul Jalal ◽  
...  
Keyword(s):  
Heat Release ◽  
Air Temperature ◽  
Engine Performance ◽  
Zone Model ◽  
Hcci Engine ◽  
Hcci Combustion ◽  
Temperature Heat ◽  
Performance And Emissions ◽  
Improved Performance ◽  
Start Of Combustion

Homogeneous Charge Compression Ignition (HCCI) engine has attracted great attention due to its improved performance and emissions compared to conventional engines. It can reduce both Nitrogen Oxides (NOx) and Particulate Matter (PM) emissions simultaneously without sacrificing the engine performance. However, controlling its combustion phasing remains a major challenge due to the absence of direct control mechanism. The start of combustion is entirely initiated by the chemical reactions inside the combustion chamber, resulted from the compression of its homogeneous mixtures. Varying some critical engine parameters can play a significant role to control the combustion phasing of HCCI engine. This paper investigates the characteristics of HCCI combustion fuelled with n-heptane (C7H16) using single-zone model computational software. The model enabled the combustion object to vary from cycle to cycle. Detailed simulations were conducted to evaluate the effects of air fuel ratio (AFR), compression ratio (CR) and intake air temperature on the in-cylinder pressure and heat release rate. The simulation results showed that the single-zone model was able to predict the two-stage kinetic combustion of HCCI engine; the Low Temperature Heat Release (LTHR) and the High Temperature Heat Release (HTHR) regions. It was found that minor changes in AFR, CR and inlet air temperature led to major changes in the HCCI combustion phasing.

Computational Analysis of an Early Direct Injected HCCI Engine with Turbocharger Using Bio Ethanol and Diesel Blends

2015 ◽  
Vol 812 ◽  
pp. 70-78
Author(s):  
S. Natarajan ◽  
A.U. Meeanakshi Sundareswaran ◽  
S. Arun Kumar ◽  
N.V. Mahalakshmi
Keyword(s):  
Chemical Kinetics ◽  
Computational Analysis ◽  
Reaction Path ◽  
Chemical Species ◽  
Operating Conditions ◽  
Injection Time ◽  
Engine Operation ◽  
Hcci Engine ◽  
Hcci Combustion ◽  
Auto Ignition

In this paper the work deals with the computational analysis of early direct injected HCCI engine with turbocharger using the CHEMKIN-PRO software. The computational analysis was carried out in the base of auto ignition chemistry by means of reduced chemical kinetics. For this study the neat diesel and Bio ethanol diesel blend (E20) were used as fuel. The inlet pressure was increased to 1.2 bar to simulate the turbocharged engine operation. The injection time was advanced to 18° before top dead centre (BTDC) i.e., 5° BTDC than normal injection time of 23° BTDC. The equivalence ratio was kept at 0.6 (ɸ=0.6) and the combustion, emission characteristics and chemical kinetics of the combustion reaction were studied. Since pressure and temperature profiles plays a very important role in reaction path at certain operating conditions, an attempt had been made here to present a complete reaction path investigation on the formation/destruction of chemical species at peak temperature and pressure conditions. The result showed that main draw backs of HCCI combustion like higher levels of unburned hydrocarbon emissions and carbon monoxide emissions are reduced in the turbocharged operation of the HCCI engine when compared to normal HCCI engine operation without turbocharger.

scholarly journals A Study on the Performance of Combustion in a HCCI Engine Using n-Heptane by a Multi-Zone Model

2009 ◽  
Author(s):  
Hongsheng Guo ◽  
Hailin Li ◽  
W. Stuart Neill
Keyword(s):  
Numerical Simulation ◽  
Numerical Simulations ◽  
Chemical Species ◽  
Numerical Data ◽  
Operating Conditions ◽  
Zone Model ◽  
Nox Emissions ◽  
Hcci Engine ◽  
Operation Conditions ◽  
Wide Range

A study of n-heptane combustion in an HCCI engine was carried out by a multi-zone numerical simulation that covers a complete engine cycle. A reaction mechanism that includes 177 chemical species and 1638 reactions was used. The results of the numerical simulations were compared to existing experimental data for a range of air/fuel ratios, compression ratios and engine speeds. It is shown that the numerical simulation is able to reasonably capture the experimental cylinder pressure data over a wide range of operation conditions. It also provides a qualitative trend of CO emissions. The numerical simulation overpredicted the combustion at some operating conditions, such as at extremely high air/fuel ratios and higher engine speeds. Some differences were observed between the experimental and numerical data for NOX emissions. The numerical simulation predicted a monotonic decrease in NOX emissions as air/fuel ratio increased or compression ratio decreased, while an increase in NOX emissions was observed experimentally when combustion became very weak at extremely high air/fuel ratios or low compression ratios. It is suggested that further experiments and numerical simulations should be performed to explain this discrepancy.

An Optically-Accessible Combustion Apparatus for Direct-Injection Natural Gas Ignition Studies

2007 ◽  
Author(s):  
Mark A. Fabbroni ◽  
Stewart Xu Cheng ◽  
Vito Abate ◽  
James S. Wallace
Keyword(s):  
Natural Gas ◽  
Initial Conditions ◽  
Direct Injection ◽  
Engine Performance ◽  
Constant Volume ◽  
Compression Process ◽  
Compression Ignition Engine ◽  
Engine Cylinder ◽  
Experimental Apparatus ◽  
Constant Volume Combustion

Research investigating direct injection natural gas (DING) diesel engines shows many attractions in engine performance including higher thermal efficiency and higher power output as well as significant improvement of exhaust emissions. However, ignition of injected natural gas is difficult and requires some form of ignition assist, such as a diesel pilot or a glow plug. This paper introduces the experimental apparatus used for compression ignition engine studies in the Engine Research and Development Laboratory (ERDL) at University of Toronto. The apparatus consists of an optically accessible constant volume combustion bomb coupled to a single-cylinder Cooperative Fuel Research (CFR) engine through its spark plug port. The engine provides rapid compression to create realistic engine conditions in the combustion bomb and also scavenges the combustion products. During the engine compression process, the piston pushes the air from the engine cylinder to the constant volume combustion bomb, generating high-pressure, high-temperature initial conditions and a strong swirling air flow in the constant volume combustion bomb. Experiments were conducted to measure temperatures and pressures in the constant volume combustion bomb for a range of initial conditions. The experiments were complemented by numerically modeling the whole domain of the CFR engine cylinder, the constant volume combustion bomb, and the port connecting them using a modified KIVA-3V code. The code computes spatially and temporally resolved pressure, temperature and swirl intensity in the constant volume combustion bomb during the compression process. The experimental and the numerical results are in satisfactory agreement and provide validation of the initial conditions in the constant volume combustion bomb for subsequent studies of injection and ignition.

LQR-Based Control of a Two Zone HCCI Engine Model

2008 ◽  
Author(s):  
Varun Tandra ◽  
Nilabh Srivastava
Keyword(s):  
Environmental Concern ◽  
Research Effort ◽  
Engine Performance ◽  
Linear Quadratic Regulator ◽  
Current Debate ◽  
Zone Model ◽  
Compression Ignition ◽  
Linear Quadratic ◽  
Hcci Engine ◽  
Peak Pressures

With growing environmental concern, automobile energy consumption has become a key element in the current debate on global warming. Over the last two decades, significant research effort has been directed towards developing advanced engine technologies such as HCCI (Homogeneous Charge Compression Ignition) that not only lower the exhaust emissions from an automobile, but also offers reprieve from conventional gasoline/diesel usage by promising fuel-flexibility. HCCI offers better engine performance and reduced emissions by emulating the best features of both CI (compression-ignition) and SI (spark-ignition) engines. However, accurate and reliable combustion control of an HCCI engine is an inherently challenging task. Many single-zone control-oriented HCCI models reported in literature fail to accurately estimate the peak pressures, ignition timings, and especially cylinder temperatures. Although certain multi-zone models of HCCI engines based on detail chemical kinetics and fluid mechanics have been developed, such models are too complex for the synthesis of fast and reliable control laws. Thus, considerable research effort has been directed in the present work to develop a physics-based two-zone model of a single-cylinder HCCI engine accounting for temperature and concentration inhomogeneities within the cylinder for better prediction of peak pressures, combustion timings, and exhaust temperatures. The results obtained were in consonance with the computationally intensive multi-zone models. The nonlinear model for peak pressure, ignition timing and exhaust temperature was linearized about an operating point to facilitate the development of an effective LQR (linear quadratic regulator). The model inputs include variable valve timings to effectively control peak pressures, exhaust temperatures and ignition timings.

Implementation Challenges and Solutions for Homogenous Charge Compression Ignition Combustion in Diesel Engines

2014 ◽  
Author(s):  
Usman Asad ◽  
Ming Zheng ◽  
David Ting ◽  
Jimi Tjong
Keyword(s):  
High Pressure ◽  
Diesel Engines ◽  
Performance Metrics ◽  
Pressure Rise ◽  
Engine Performance ◽  
Injection Pressure ◽  
Combustion Stability ◽  
Compression Ignition ◽  
Hcci Combustion ◽  
Homogenous Charge Compression Ignition

Homogenous charge compression ignition (HCCI) combustion in diesel engines can provide for cleaner operation with ultra-low NOx and soot emissions. While HCCI combustion has generated significant attention in the last decade, however, to date, it has seen very limited application in production diesel engines. HCCI combustion is typically characterized by earlier than top-dead-center (pre-TDC) phasing, very high pressure rise rates, short combustion durations and minimal control over the timing of the combustion event. To offset the high reactivity of the diesel fuel, large amounts of EGR (30 to 60%) are usually applied to postpone the initiation of combustion, shift the combustion towards TDC and alleviate to some extent, the high pressure rise rates and the reduced energy efficiency. In this work, a detailed analysis of HCCI combustion has been carried out on a high-compression ratio, single-cylinder diesel engine. The effects of intake boost, EGR quantity/temperature, engine speed, injection scheduling and injection pressure on the operability limits have been empirically determined and correlated with the combustion stability, emissions and performance metrics. The empirical investigation is extended to assess the suitability of common alternate fuels (n-butanol, gasoline and ethanol) for HCCI combustion. On the basis of the analysis, the significant challenges affecting the real-world application of HCCI are identified, their effects on the engine performance quantified and possible solutions to overcome these challenges explored through both theoretical and empirical investigations. This paper intends to provide a comprehensive summary of the implementation issues affecting HCCI combustion in diesel engines.

Numerical Simulation of the Effect of Ethanol on Diesel HCCI Combustion Using Multi-Zone Model

2012 ◽  
Vol 229-231 ◽  
pp. 78-81 ◽  
Author(s):  
Su Wei Zhu ◽  
Chun Mei Wang ◽  
Ye Jian Qian ◽  
Li Jun Ou ◽  
Hui Chun Wang
Keyword(s):  
Low Temperature ◽  
Zone Model ◽  
Compression Ignition ◽  
Low Temperature Oxidation ◽  
Temperature Oxidation ◽  
Hcci Combustion ◽  
Active Intermediate ◽  
Simulation Results ◽  
Homogenous Charge Compression Ignition ◽  
Heat Released

This study investigates the potential of controlling diesel homogenous charge compression ignition (HCCI) combustion by blending ethanol, which inhibits low temperature oxidation offering the possibility to control ignition in HCCI combustion. The simulation results from a multi-zone model show that the ethanol reduces the key active intermediate radicals OH, CH2O, H2O2, delays the low temperature oxidation reaction (LTR), reduces the heat released during LTR stage. As a result, it retards the main combustion stage.

Numerical Simulation of the Plasma-Assisted Combustion of Methane HCCI

2013 ◽  
Vol 385-386 ◽  
pp. 19-22
Author(s):  
Hui Chun Wang ◽  
Chun Mei Wang ◽  
Su Wei Zhu ◽  
Xiao Liu
Keyword(s):  
Ignition Delay ◽  
Delay Time ◽  
Ignition Delay Time ◽  
Volume Fraction ◽  
Zone Model ◽  
Discharge Process ◽  
Lean Burn ◽  
Lean Combustion ◽  
Hcci Combustion ◽  
Homogenous Charge Compression Ignition

To enhance the lean combustion of methane homogenous charge compression ignition (HCCI) engine and expand the lean-burn limit, a non-equilibrium plasma kinetic model has been used to study the discharge process of methane-air mixture numerically. The effect of the discharge productions on the methane HCCI combustion are studied numerically by using a CHEMKIN-based multi-zone model. The simulation results show that the discharge produced reactive radicals, such as H, O and CH3. These radicals can enhance the combustion of CH4 fueled HCCI significantly. Introduction of 1% (volume fraction of the fuel) of H reduces the ignition delay time of HCCI combustion (with equivalence fuel / air ratio of Φ = 0.5) by about 13 crank angle degrees (°CA), adding the same amount of O reduces the ignition delay time by about 10°CA. Further research shows that, with the increase in the above radicals, the combustion enhancement becomes stronger.

Sign in / Sign up

Export Citation Format

Share Document