Analysis of the HCCI Combustion of a Turbocharged Truck Engine Using a Stochastic Reactor Model

2002 ◽  
Author(s):  
Luca Montorsi ◽  
Fabian Mauss ◽  
Gian Marco Bianchi ◽  
Amit Bhave ◽  
Markus Kraft
Keyword(s):  
Numerical Simulation ◽  
Combustion Process ◽  
Critical Issue ◽  
Chemical Kinetic ◽  
Reactor Model ◽  
Hcci Combustion ◽  
Hcci Engines ◽  
Homogeneous Reactor ◽  
Power Code ◽  
Truck Engine

Homogeneous Charge Compression Ignition (HCCI) engines arouse great interest due to their high thermal efficiency and very low emissions of nitrogen oxides (NOx) and particulates. Critical issue of the HCCI combustion is the control of the engine since the combustion process is mostly dominated by chemical kinetics. Therefore the accurate assessment of the chemical kinetic is fundamental in numerical simulation of this kind of engines. Experimentally it has been demonstrated that even in HCCI engine the charge within the cylinder is not fully homogeneous, but many quantities, such as temperature, density and equivalence ratio, vary along the combustion chamber. These inhomogeneities influence the combustion process and yield the homogeneous reactor model to be not completely adequate to simulate HCCI combustion. This paper focuses on the use of a stochastic rector model in order to account for temperature inhomogeneities in the numerical simulation of the HCCI combustion. Moreover, the chemical kinetic code has been coupled to GT – Power Code, a 1-D fluid – dynamics code, in order to accurately simulate the operation of a turbocharged truck engine.

Analysis of the HCCI Combustion of a Turbocharged Truck Engine Using a Stochastic Reactor Model

2003 ◽  
Author(s):  
Luca Montorsi ◽  
Fabian Mauss ◽  
Gian Marco Bianchi ◽  
Amit Bhave ◽  
Markus Kraft
Keyword(s):  
Numerical Simulation ◽  
Combustion Process ◽  
Critical Issue ◽  
Chemical Kinetic ◽  
Reactor Model ◽  
Hcci Combustion ◽  
Hcci Engines ◽  
Homogeneous Reactor ◽  
Power Code ◽  
Truck Engine

Homogeneous Charge Compression Ignition (HCCI) engines arouse great interest due to their high thermal efficiency and very low emissions of nitrogen oxides (NOx) and particulates. Critical issue of the HCCI combustion is the control of the engine since the combustion process is mostly dominated by chemical kinetics. Therefore the accurate assessment of the chemical kinetic is fundamental in numerical simulation of this kind of engines. Experimentally it has been demonstrated that even in HCCI engine the charge within the cylinder is not fully homogeneous, but many quantities, such as temperature, density and equivalence ratio, vary along the combustion chamber. These inhomogeneities influence the combustion process and yield the homogeneous reactor model to be not completely adequate to simulate HCCI combustion. This paper focuses on the use of a stochastic rector model in order to account for temperature inhomogeneities in the numerical simulation of the HCCI combustion. Moreover, the chemical kinetic code has been coupled to GT - Power Code, a 1-D fluid–dynamics code, in order to accurately simulate the operation of a turbocharged truck engine.

scholarly journals Effects of EGR and Alternative Fuels on Homogeneous Charge Compression Ignition (HCCI) Combustion Mode

2021 ◽  
Vol 16 (2) ◽  
pp. 135-144
Author(s):  
Saliha Mohammed Belkebir ◽  
Benyoucef Khelidj ◽  
Miloud Tahar Abbes
Keyword(s):  
Alternative Fuels ◽  
Ignition Time ◽  
Combustion Process ◽  
Chemical Species ◽  
Pollutant Emissions ◽  
Combustion Mode ◽  
Hcci Combustion ◽  
Hcci Engines ◽  
Homogeneous Reactor ◽  
Gas Recirculation

We present in this article an analysis of the impacts of the exhaust gas recirculation (EGR) and alternative fuels on HCCI combustion mode. The objective is to reduce the pollutant emissions below the levels of established pollution standards. The ANSYS CHEMKIN-Pro software and the combined chemical kinetics mechanism were used to perform simulations for a closed homogeneous reactor under conditions relevant to HCCI engines. The calculation process is based on one single-zone in the combustion chamber. Numerical simulation has proven the ability of the models adopted, which use the essential mechanisms of the fuel combustion process, to reproduce, among other things, the evolution of the formation of chemical species. This study showed that adding hydrogen (H2) to methane (CH4) is an interesting alternative fuel because it reduces ignition time. It was concluded that an increase of EGR rate conducts to a slower combustion process, lower temperatures, and the reduction of nitrogen oxide (NOX) emissions.

Chemical Kinetic Analysis of a Flameless Gas Turbine Combustor

2008 ◽  
Author(s):  
G. Arvind Rao ◽  
Yeshayahou Levy ◽  
Ephraim J. Gutmark
Keyword(s):  
Combustion Chamber ◽  
Kinetic Analysis ◽  
Gas Turbine ◽  
Flame Temperature ◽  
Plug Flow ◽  
Combustion Process ◽  
Chemical Reactor ◽  
Chemical Kinetic ◽  
Combustion Regime ◽  
Reactor Model

Flameless combustion (FC) is one of the most promising techniques of reducing harmful emissions from combustion systems. FC is a combustion phenomenon that takes place at low O2 concentration and high inlet reactant temperature. This unique combination results in a distributed combustion regime with a lower adiabatic flame temperature. The paper focuses on investigating the chemical kinetics of an prototype combustion chamber built at the university of Cincinnati with an aim of establishing flameless regime and demonstrating the applicability of FC to gas turbine engines. A Chemical reactor model (CRM) has been built for emulating the reactions within the combustor. The entire combustion chamber has been divided into appropriate number of Perfectly Stirred Reactors (PSRs) and Plug Flow Reactors (PFRs). The interconnections between these reactors and the residence times of these reactors are based on the PIV studies of the combustor flow field. The CRM model has then been used to predict the combustor emission profile for various equivalence ratios. The results obtained from CRM model show that the emission from the combustor are quite less at low equivalence ratios and have been found to be in reasonable agreement with experimental observations. The chemical kinetic analysis gives an insight on the role of vitiated combustion gases in suppressing the formation of pollutants within the combustion process.

A Skeletal Chemical Kinetic Model for the HCCI Combustion Process

2002 ◽  
Author(s):  
Jincai Zheng ◽  
Weiying Yang ◽  
David L. Miller ◽  
Nicholas P. Cernansky
Keyword(s):  
Kinetic Model ◽  
Combustion Process ◽  
Chemical Kinetic ◽  
Chemical Kinetic Model ◽  
Hcci Combustion

A Skeletal Chemical Kinetic Model of PRF Oxidation for HCCI Engines

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Qingfeng Zhang ◽  
Zhaolei Zheng ◽  
Zuwei He ◽  
Ying Wang
Keyword(s):  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Chemical Kinetic Model ◽  
Molecule Reaction ◽  
Hcci Combustion ◽  
Hcci Engines ◽  
Reliable Performance ◽  
Primary Reference ◽  
Primary Reference Fuels ◽  
Good Agreement

A skeletal chemical kinetic mechanism, including 42 species and 71 reactions for the oxidation of primary reference fuel (PRF), was developed and applied to model homogeneous charge compression ignition (HCCI) combustion after various experiments and available mechanisms for PRF oxidation being reviewed and the performance of mechanisms applied to experiments relevant to HCCI engines being analyzed. The ignition delay predicted by the skeletal mechanism showed good agreement with experiments for different fuels over the temperature range 667-1350K. Validation was also performed with experiments from HCCI engines, and good agreement was obtained for the primary reference fuels. The results show that the present PRF mechanism gives reliable performance for HCCI combustion predictions. Sensitivity analysis indicates that for PRF70 and PRF91.8 under HCCI conditions, H-atom abstraction from iso-octane molecule reaction and OH addition to n-heptane molecule have large influence, and CH2O, CH3 are very important intermediate species.

Modeling Direct-Injection Gasoline HCCI Combustion Using Detailed Chemistry and CFD

2001 ◽  
Author(s):  
Song-Charng Kong ◽  
Rolf D. Reitz
Keyword(s):  
Turbulent Mixing ◽  
Direct Injection ◽  
Combustion Process ◽  
Reaction Rates ◽  
Injection Timing ◽  
Detailed Chemical Kinetics ◽  
Detailed Chemistry ◽  
Hcci Combustion ◽  
Wide Range ◽  
Hcci Engines

Abstract Detailed chemical kinetics was implemented into an engine CFD code to study the combustion process in Homogeneous Charge Compression Ignition (HCCI) engines. The CHEMKIN code was implemented into KIVA-3V such that the chemistry and flow solutions were coupled. Effects of turbulent mixing on the reaction rates were also considered. The model was validated using experimental data from a direct-injection Caterpillar engine operated in the HCCI mode using gasoline. The results show that good levels of agreement were obtained using the present KIVA/CHEMKIN model for a wide range of engine conditions including various injection timings, engine speeds, and loads. It was found that the effects of turbulent mixing on the reaction rates needed to be considered to correctly simulate the combustion phasing. It was also found that the presence of residual radicals could enhance the mixture reactivity and hence shorten the ignition delay time. The NOx emissions were found to increase as the injection timing was retarded, in agreement with experimental results.

Detailed Chemical Kinetic Simulation of Natural Gas HCCI Combustion: Gas Composition Effects and Investigation of Control Strategies

2000 ◽  
Vol 123 (2) ◽  
pp. 433-439 ◽  
Author(s):  
D. Flowers ◽  
S. Aceves ◽  
C. K. Westbrook ◽  
J. R. Smith ◽  
R. Dibble
Keyword(s):  
Natural Gas ◽  
Control Strategies ◽  
Chemical Kinetic ◽  
Gas Composition ◽  
Gas Combustion ◽  
Combustion Gas ◽  
Hcci Engine ◽  
Hcci Combustion ◽  
Hcci Engines ◽  
Natural Gas Combustion

This paper uses the HCT (hydrodynamics, chemistry and transport) chemical kinetics code to analyze natural gas combustion in an HCCI engine. The HCT code has been modified to better represent the conditions existing inside an engine, including a wall heat transfer correlation. Combustion control and low power output per displacement remain as two of the biggest challenges to obtaining satisfactory performance out of an HCCI engine, and these challenges are addressed in this paper. The paper considers the effect of natural gas composition on HCCI combustion, and then explores three control strategies for HCCI engines: DME (dimethyl ether) addition, intake heating and hot EGR addition. The results show that HCCI combustion is sensitive to natural gas composition, and an active control may be required to compensate for possible changes in composition. Each control strategy has been evaluated for its influence on the performance of an HCCI engine.

NUMERICAL SIMULATION FOR REDUCED CHEMICAL KINETIC MECHANISM: A CASE FOR CARBON MONOXIDE AND HYDROGEN

2018 ◽  
Author(s):  
Rafael Torres Teixeira ◽  
Rafaela Sehnem ◽  
Letícia Kaufmann ◽  
Daniela Buske ◽  
Regis Sperotto de Quadros
Keyword(s):  
Numerical Simulation ◽  
Carbon Monoxide ◽  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Chemical Kinetic Mechanism

Numerical Simulation of Premixed Propane/Air Flame Propagation Using a Dynamically Thickened Flame Approach

2013 ◽  
Vol 444-445 ◽  
pp. 1574-1578 ◽  
Author(s):  
Hua Hua Xiao ◽  
Zhan Li Mao ◽  
Wei Guang An ◽  
Qing Song Wang ◽  
Jin Hua Sun
Keyword(s):  
Numerical Simulation ◽  
Flame Propagation ◽  
Numerical Study ◽  
Vortex Motion ◽  
Combustion Process ◽  
Single Step ◽  
Premixed Combustion ◽  
Premixed Flame ◽  
Flame Surface ◽  
Arrhenius Kinetics

A numerical study of premixed propane/air flame propagation in a closed duct is presented. A dynamically thickened flame (TF) method is applied to model the premixed combustion. The reaction of propane in air is taken into account using a single-step global Arrhenius kinetics. It is shown that the premixed flame undergoes four stages of dynamics in the propagation. The formation of tulip flame phenomenon is observed. The pressure during the combustion process grows exponentially at the finger-shape flame stage and then slows down until the formation of tulip shape. After tulip formation the pressure increases quickly again with the increase of the flame surface area. The vortex motion behind the flame front advects the flame into tulip shape. The study indicates that the TF model is quite reliable for the investigation of premixed propane/air flame propagation.

Sign in / Sign up

Export Citation Format

Share Document