IRis

Title

Rate-controlled constrained-equilibrium (RCCE) modelling of C1-hydrocarbon fuels

Author(s)

Mohammad Janbozorgi, Northeastern University

Advisor(s)

M. (Mohamad) Metghalchi

Contributor(s)

M. (Mohamad) Metghalchi, Y. A. (Yiannis A.) Levendis, M. Reza H. Sheikhi, James C. Keck

Date of Award

8-2011

Date Accepted

8-2011

Degree Grantor

Northeastern University

Degree Level

Ph.D.

Degree Name

Doctor of Philosophy

Department or Academic Unit

College of Engineering. Department of Mechanical and Industrial Engineering.

Keywords

C1 Hydrocarbon Fuels, Model Order Reduction, Rate-Controlled Constrained-Equilibrium, RCCE

Disciplines

Heat Transfer, Combustion | Mechanical Engineering

Abstract

This dissertation is focused on an important problem faced in chemical kinetic modelling, that is, model order reduction. The method of Rate-Controlled Constrained-Equilibrium (RCCE) firmly based on the Second Law of Thermodynamics, has been further developed and used for this purpose. The main challenge in RCCE lies in selection of the kinetic constraints. Two classes of problems were looked at: 1) far-from equilibrium problem of ignition and 2) relaxations away from equilibrium due to interactions with the environment.

Regarding the first class, a unified RCCE model for combustion of C1-hydrocarbon fuels (CH₄, CH₃OH and CH₂O) and their corresponding reduced model swere developed. The model is composed of a set of structural constraints controlling the chemical conversion from fuel into combustion products.

For the second class it was shown that a subset of the constraints identified in the first class is able to equally well predict the main features of expansion of combustion products within the power stroke of an internal combustion engine as well as supersonic expansion through a rocket nozzle and also expansion through a heat exchanger as amodel for sudden cooling in gas turbine.

A method based on the degree of disequilibrium of chemical reactions was also suggested for selection of kinetic constraints. This approach has potentials to reduce the level of chemical knowledge required for selection of kinetic constraints and it was shown how the application of this method reproduces the generalized constraints used in the second class of problems without any chemical intuition.

Document Type

Dissertation

Rights Holder

Mohammad Janbozorgi

Permanent URL

http://hdl.handle.net/2047/d20002647

Recommended Citation

Janbozorgi, Mohammad, "Rate-controlled constrained-equilibrium (RCCE) modelling of C1-hydrocarbon fuels" (2011). Mechanical Engineering Dissertations. Paper 26. http://hdl.handle.net/2047/d20002647