Comparing Single-Step and Multi-Step Chemistry Using The Laminar and Turbulent Characteristic Time Combustion Model In Two Diesel Engines

2002 ◽  
Author(s):  
Ossi Kaario ◽  
Martti Larmi ◽  
Franz Tanner
Keyword(s):  
Diesel Engines ◽  
Characteristic Time ◽  
Single Step ◽  
Combustion Model ◽  
Turbulent Characteristic

Multidimensional Modeling of Diesel Ignition and Combustion Using a Multistep Kinetics Model

1993 ◽  
Vol 115 (4) ◽  
pp. 781-789 ◽  
Author(s):  
S.-C. Kong ◽  
R. D. Reitz
Keyword(s):  
Chemical Kinetics ◽  
Diesel Engines ◽  
Characteristic Time ◽  
Kinetics Model ◽  
Combustion Model ◽  
Model Parameters ◽  
Ignition Process ◽  
Time Model ◽  
Combustion Heat ◽  
Ignition And Combustion

Ignition and combustion mechanisms in diesel engines were studied using the KIVA code, with modifications to the combustion, heat transfer, crevice flow, and spray models. A laminar-and-turbulent characteristic-time combustion model that has been used successfully for spark-ignited engine studies was extended to allow predictions of ignition and combustion in diesel engines. A more accurate prediction of ignition delay was achieved by using a multistep chemical kinetics model. The Shell knock model was implemented for this purpose and was found to be capable of predicting successfully the autoignition of homogeneous mixtures in a rapid compression machine and diesel spray ignition under engine conditions. The physical significance of the model parameters is discussed and the sensitivity of results to the model constants is assessed. The ignition kinetics model was also applied to simulate the ignition process in a Cummins diesel engine. The post-ignition combustion was simulated using both a single-step Arrhenius kinetics model and also the characteristic-time model to account for the energy release during the mixing-controlled combustion phase. The present model differs from that used in earlier multidimensional computations of diesel ignition in that it also includes state-of-the-art turbulence and spray atomization models. In addition, in this study the model predictions are compared to engine data. It is found that good levels of agreement with the experimental data are obtained using the multistep chemical kinetics model for diesel ignition modeling. However, further study is needed of the effects of turbulent mixing on post-ignition combustion.

scholarly journals Optimization of Fuel Injection Parameters of Moringa oleifera Biodiesel-Diesel Blend for Engine-Out-Responses Improvements

Symmetry ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 982
Author(s):  
Yew Heng Teoh ◽  
Heoy Geok How ◽  
Farooq Sher ◽  
Thanh Danh Le ◽  
Hwai Chyuan Ong ◽  
...  
Keyword(s):  
Diesel Engines ◽  
Fossil Fuels ◽  
Moringa Oleifera ◽  
Fuel Injection ◽  
Injection Pressure ◽  
Single Step ◽  
Rapid Decline ◽  
Fuel Blend ◽  
Combustion Dynamics ◽  
Rsm Optimization

Biodiesel has gained popularity in diesel engines as a result of the rapid decline of fossil fuels and population growth. The processing of biodiesel from non-edible Moringa Oleifera was investigated using a single-step transesterification technique. Both fuels had their key physicochemical properties measured and investigated. In a common-rail diesel engine, the effects of MB50 fuel blend on the symmetric characteristics of engine-out responses were evaluated under five load settings and at 1000 rpm. As compared to standard diesel, MB50 increased brake thermal efficiency (BTE), and nitrogen oxides (NOx) emissions while lowering brake specific fuel consumption (BSFC), and smoke emissions for all engine loads. A further study of injection pressure and start of injection (SOI) timing for MB50 fuel was optimized using response surface methodology (RSM). The RSM optimization resulted in improved combustion dynamics due to symmetry operating parameters, resulting in a simultaneous decrease in NOx and smoke emissions without sacrificing BTE. RSM is an efficient optimization method for achieving optimal fuel injection parameter settings, as can be deduced. As a result, a clearer understanding of the use of MB50 fuel in diesel engines can be given, allowing for the best possible engine efficiency.

scholarly journals Real-time capable virtual NOx sensor for diesel engines based on a two-Zone thermodynamic model

2018 ◽  
Vol 73 ◽  
pp. 11
Author(s):  
Rok Vihar ◽  
Urban Žvar Baškovič ◽  
Tomaž Katrašnik
Keyword(s):  
Real Time ◽  
Diesel Engines ◽  
Thermodynamic Model ◽  
Direct Injection ◽  
Control Unit ◽  
Combustion Model ◽  
Data Sets ◽  
Modeling Framework ◽  
Using Data ◽  
High Level

This paper presents a control-oriented thermodynamic model capable of predicting nitrogen oxides (NOx) emissions in diesel engines. It is derived from zero-dimensional combustion model using in-cylinder pressure as the input. The methodology is based on a two-zone thermodynamic model which divides the combustion chamber into a burned and unburned gas zone. The original contribution of proposed method arises from: (1) application of a detailed two-zone modeling framework, developed in a way that the thermodynamic equations could be solved in a closed form without iterative procedure, which provides the basis for achieving high level of predictiveness, on the level of real-time capable models and (2) introduction of relative air-fuel ratio during combustion as a main and physically motivated calibration parameter of the NOx model. The model was calibrated and validated using data sets recorded in two different direct injection diesel engines, i.e. a light and a heavy-duty engine. The model is suitable for real-time applications since it takes less than a cycle to complete the entire closed cycle thermodynamic calculation including NOx prediction, which opens the possibility of integration in the engine control unit for closed-loop or feed-forward control.

A Computational Model for the Study of Gas Turbine Combustor Dynamics

1999 ◽  
Vol 121 (2) ◽  
pp. 243-248 ◽  
Author(s):  
D. M. Costura ◽  
P. B. Lawless ◽  
S. H. Fankel
Keyword(s):  
Gas Turbine ◽  
Mass Conservation ◽  
Single Step ◽  
Combustion Model ◽  
Reacting Flow ◽  
Gas Turbine Combustor ◽  
Splitting Algorithm ◽  
Simulation Code ◽  
One Dimensional ◽  
Engine Simulation

A dynamic combustor model is developed for inclusion into a one-dimensional full gas turbine engine simulation code. A flux-difference splitting algorithm is used to numerically integrate the quasi-one-dimensional Euler equations, supplemented with species mass conservation equations. The combustion model involves a single-step, global finite-rate chemistry scheme with a temperature-dependent activation energy. Source terms are used to account for mass bleed and mass injection, with additional capabilities to handle momentum and energy sources and sinks. Numerical results for cold and reacting flow for a can-type gas turbine combustor are presented. Comparisons with experimental data from this combustor are also made.

Phenomenological two-phase multi-zone combustion model for direct-injection diesel engines

2016 ◽  
Vol 17 (5) ◽  
pp. 895-907 ◽  
Author(s):  
K. Zhang ◽  
M. Xu ◽  
J. Wei ◽  
Y. Cui ◽  
K. Deng
Keyword(s):  
Diesel Engines ◽  
Direct Injection ◽  
Combustion Model ◽  
Two Phase

Development of a time-scale interaction combustion model and its application to gasoline and diesel engines

2009 ◽  
Vol 32 (2) ◽  
pp. 2751-2758 ◽  
Author(s):  
Atsushi Teraji ◽  
Yoshihiro Imaoka ◽  
Tsuyoshi Tsuda ◽  
Toru Noda ◽  
Masaaki Kubo ◽  
...  
Keyword(s):  
Diesel Engines ◽  
Time Scale ◽  
Combustion Model ◽  
Scale Interaction

Application of a multi-zone combustion model to investigate the NOx reduction potential of two-stroke marine diesel engines using EGR

2015 ◽  
Vol 157 ◽  
pp. 814-823 ◽  
Author(s):  
Spiridon I. Raptotasios ◽  
Nikolaos F. Sakellaridis ◽  
Roussos G. Papagiannakis ◽  
Dimitrios T. Hountalas
Keyword(s):  
Diesel Engines ◽  
Reduction Potential ◽  
Nox Reduction ◽  
Combustion Model ◽  
Marine Diesel
Sign in / Sign up

Export Citation Format

Share Document