Buradasınız

Anasayfa » Content

SAYISAL SİMÜLASYONLA DİZEL MOTORDA KİRLETİCİ OLUŞUM TAHMİNİ

PREDICTION OF POLLUTANT FORMATION IN DIESEL ENGINE THROUGH NUMERICAL SIMULATION

Journal Name:

  • Gazi Üniversitesi Mühendislik-Mimarlık Fakültesi Dergisi

Publication Year:

  • 2013

Key Words:

Keywords (Original Language):

Author Name
Abstract (2. Language): 
In this paper numerical technique through Computational Fluid Dynamics (CFD) codes was used in order to investigate thermo-fluid-dynamics field (velocity, pressure, temperature) in the combustion chamber of a Diesel engine. Another important objective was the possibility of modelling and prediction of pollutant formation during the combustion process in these engines. Mathematical model was based on the conservation equations of mass, momentum and energy (Favre-averaged Navier-Stokes equations). To close these equations system was add also: state relations equations, Renormalized Group Theory (RNG) k-epsilon turbulence model and spray mechanism model. Since processes in Diesel engine have not only thermo-fluid nature but also chemistry, a special attention was for chemistry models for both chemical reaction simulation and for the chemistry models of pollutants. Formation of NOx is predicted by Zeldovich mechanism. Soot formation relies on the nucleation, surface growth, coagulation and oxidation process. Result of simulation shown that thermal NOx is seen at stoichiometric mixture fraction at high temperatures, while soot formation is seen fuel-rich and relatively lowtemperature regions.
Bookmark/Search this post with
Abstract (Original Language): 
Bu çalışmada Dizel bir motorun yanma odasındaki termo-akışkan dinamiği alanını (hız, basınç, sıcaklık) araştırmak amacıyla Hesaplamalı Akışkan Dinamiği (HAD) kodları sayesinde sayısal teknik kullanıldı. Diğer bir önemli amaç, bu motorların yanma prosesindeki kirletici oluşumunun tahmin edilmesi ve modellenmesinin olabilirliğinin belirlenmesidir. Matematiksel model; kütle, momentum ve enerjinin korunumu denklemlerine dayanır (Favre-Averaged Navier-Stokes denklemleri). Bu denklem takımlarını yaklaştırmak için, ayrıca hal bağıntı denklemleri, Yeniden Normalleştirilmiş Grup Teorisi (RNG), k-epsilon türbülans modeli ve sprey mekanizması modeli eklenmiştir. Bu Diesel motordaki prosesler termo-akışkan doğasının yanı sıra kimyayı da içermesinden dolayı, hem kimyasal tepki simülasyonu hem de kirleticilerin kimyasal modeli için özel bir ilgi söz konusudur. NOx oluşumu Zeldovich mekanizmasıyla tahmin edilir. İs oluşumu; çekirdeklenme, yüzey büyümesi, koagülasyon ve oksitlenme prosesine bağlıdır. Simülasyon sonuçları gösteriyor ki; is oluşumu yakıt bakımından zengin ve nispeten düşük sıcaklığa sahip bölgelerde görülüyorken, termal NOx yüksek sıcaklıklarda stokiyometrik karışım oranında görülür.
FULL TEXT (PDF): 
PDF icon arastirmax-sayisal-simulasyonla-dizel-motorda-kirletici-olusum-tahmini.pdf
  • 1
167
172
  • Turkish

REFERENCES

References: 

1. Amsden, A. A., O'Rourke, P. J. and Butler T. D.,
“KIVA II: A Computer Program for Chemically
Reactive Flows with Sprays. Los Alamos National
Laboratory Report, LA-11560-MS. Los Alamos,
NM”, USA. 1989.
2. Bracco, F.V., “Modeling of Engine Spray”, SAE
Trans., 94, 144-167., 1985.
3. Correa, C., “Combustion Simulations Diesel
Engines Using Reduced Reaction Mechanism”. PhD
Thesis, University of Heidelberg”, Heidelberg. 2000.
4. Merker, G., Schwarz, Ch., Stiesch G. and Otto,
F., “Simulating Combustion and pollutant formation”,
Springer, Germany. 2006.
5. Naydenova, I. I., “Soot Formation Modeling
During Hydrocarbon Pyrolysis and Oxidation Behind
Shock Wave”. PhD. Thesis, University of
Heidelberg, Heidelberg. 2007.
6. Ogink, R., “Computer Modelling of HCCI
Combustion, Ph.D. Thesis, Chalmers University of
Technology”, Göteborg, Sweden. 2004.
7. Ravi, A., “CFD Simulation of Combustion
Using Automatically Reduced Reaction Mechanisms:
A Case for Diesel Engine”. PhD Thesis, University
of Heidelberg”, Heidelberg. 2007.
8. Yakhot, V. and Orzag, S. A., “Renormalization
Group Analysis of Turbulence. I. Basic Theory”,
Journal of Scientific Computing, 1, 3. 1986.
9. Zeldovich, Y. B., “The oxidation of nitrogen in
combustion and explosions”, Acta Physiochimica,
21, 577-628.”, 1946.
10. Özsezen, A.N. and Çanakcı, M., “Performance
and combustion in a direct injection diesel engine
fuelled with waste palm and canola oil methyl esters”.
J. Fac. Eng. Arch. Gazi Univ. Vol 24, No 2, 275-
284, 2009.
11. Karel, A., “Exhaust emission behaviours at
diesel engines”. J. Fac. Eng. Arch. Gazi Univ. Vol
12, No 1, 71-90, 1997.
12. Dorri, A., “Numerical simulation of thermo-fluid
dynamics fiels and prediction of pollutants formation
in Diesel engines through CFD software”. PhD
Thesis, Polytechnic University of Tirana, Tirana.
2010.
13. Labs, J. E. and Parker, T. E., “A Comparison of
Single Shot Diesel Spray Combustion Emissions with
Trends Predicted by a Conceptual Model,
Combustion Science and Technology, 179,1159-
1182”, 2007.

Thank you for copying data from http://www.arastirmax.com