A Semi-Analytical Finite Rate Two-Reactor Model for Gas Turbine Combustors

Abstract

A gas turbine combustor is modeled using a two-reactor, finite-rate mixing and chemistry gas particle approach. The first reactor, used to simulate combustion in the primary zone, permits independent definition of the rates of macromixing and micromixing within the reactor, and the amount of premixing of fuel and air entering the reactor. Finite-rate macromixing is simulated by consideration of the fluid particle residence time distribution frequency function and the ages of the particles in the reactor. Finite-rate micromixing is simulated using a modified Coalescence-Dispersion (C-D) model. The second reactor model simulates combustion in the dilution zone of the combustor, and is modeled as a plug flow reactor with cross-flowing jets of dilution air and co-flowing streams of cooling film air. The primary zone reactor model predicts physically reasonable trends in mean temperature, and CO and NOx emissions as the macromixing and micromixing parameters are varied with respect to the perfectly-stirred reactor limit. The model also has shown to predict the correct trends in modeling NOx and CO emissions from aircraft engine gas turbine combustors.

Dry Low Emissions Premixer CCD Modeling and Validation

“…2) "Anchored" CCD The feasibility of this approach for diffusion flame combustors has been described by Danis et al (1996Danis et al ( , 1997, and Tonouchi et al (1997) for analyses of existing combustors, as well as a design tool for a new combustor. In order to develop and demonstrate the use of anchored CCD approach for ultra-low emissions combustors including land-based Dry Low Emissions (DLE) engines (e.g., Leonard and Stegmaier (1993)), we must understand the most critical fundamental processes of fuel/air mixing in complex swirling flows undergoing vortex breakdown as encountered in, for example, Dual Annular Counter-Rotating Swirlers (DACRS) described by Joshi eta].…”

Application of a Micro-/Macro-Mixing Two Reactor Model to a Single-Cup Low-Emissions Combustor

“…The secondary reactor models the approximately plug flow of the gases as they exit the primary zone and pass through the intermediate and secondary zones. A full description of the GPMC two-reactor model was given in the previous paper (Tonouchi, et aL, 1997) but is briefly described below.…”

“…In a previous paper, a semi-analytical model of a gas turbine combustor, the Gas Particle Monte Carlo (GPMC) model, was described (Tonouchi, et a!., 1997). The GPMC model was initially based upon the micro/macro-mixing reactor model of Tonouchi and Pratt (1995;1996).…”

“…Due to the considerable resources required for full computational combustion dynamics simulations, simplified design tools are required for rapid analysis of a large number of design variable combinations. In a previous paper, a semi-analytical model of a gas turbine combustor was described (Tonouchi, et aL, 1997). The model employs a gas particle Monte Carlo technique to simulate the effects of finite-rate micro-and macro-mixing, including full detailed chemical kinetics (Bowman, et aL, 1997).…”

Design methodology for a lean premixed prevaporized can combustor

“…Air from dilution holes have used more complex networks to improve the accuracy of these models by adding reactors for the pilot, cooling slots, and other features of interest (Rizk & Mongia, 1993b,a, 1995aTonouchi et al , 1998;Andreini & Facchini, 2002).…”