Doctoral Dissertations


“The present study considers combustion of hydrogen in IC engines. In general, the work focuses on simulating the engine performance and emissions at different operation parameters, and using optimization techniques. Task I work deals with the engine performance and emissions of a single cylinder spark-ignition (SI) engine fueled by hydrogen. The engine was simulated at different equivalence ratios, exhaust gas recirculation (EGR) and ignition timing. The results indicate that NOx emissions, engine power, and efficiency are reduced by increasing EGR level, and increased with increasing equivalence ratio and advanced ignition timing. The best operating conditions for hydrogen engines were obtained by solving the multi-objective problem of maximizing engine power and efficiency while minimizing the NOx. Task II deals with the engine performance and emissions of dual-fuel CI engines fueled by a hydrogen/diesel mixture. The engine was simulated under conditions of various hydrogen levels (%) by energy, diesel injection timing, and EGR levels (%). More hydrogen present inside the engine cylinder led to lower soot emissions, higher thermal efficiency, and higher NOx emissions. Ignition timing delayed as the hydrogen rate increased, due to a delay in OH radical formation. Exhaust gas recirculation (EGR) method and diesel injection timing were considered as well, due to their potential effects on the engine outputs. To obtain the best possible maximum efficiency along with lower NOx and soot emissions, optimization methods in (Task III) for the operating parameters were considered. Multi-objective problem with conflicting objectives was solved by using regression analysis, artificial neural networks, and genetic algorithms”--Abstract, page iv.


Köylü, Ümit Ö. (Ümit Özgür)

Committee Member(s)

Sheffield, John W.
Drallmeier, J. A.
Chandrashekhara, K.
Samaranayake, V. A.


Mechanical and Aerospace Engineering

Degree Name

Ph. D. in Mechanical Engineering


The authors are thankful to the Libyan government for financial support.


Missouri University of Science and Technology

Publication Date

Summer 2020

Journal article titles appearing in thesis/dissertation

  • Multi-objective optimization of operating parameters for hydrogen fueled spark-ignition engines
  • Influence of operating parameters on performance and emissions for a compression-ignition engine fueled by hydrogen/diesel mixtures
  • Multi-objective optimization of operating parametersfor a H2/diesel dual-fuel compression-ignition engine


xiii, 124 pages

Note about bibliography

Includes bibliographic references.


© 2020 Abdulhakim Issa Jabbr, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 11747

Electronic OCLC #