Feature-Parameter-Criterion for Predicting Lean Blowout Limit of Gas Turbine Combustor and Bluff Body Burner

Hongtao Zheng,Zhibo Zhang,Zhiming Li,Yajun Li

doi:10.1155/2013/939234

Abstract

Lean blowout (LBO) limit is one of the most important combustor parameters. A new method named Feature-Parameter-Criterion (FPC) for predicting LBO limit has been put forward in the present work. A computational fluid dynamics (CFD) software FLUENT has been used to simulate the process of LBO of gas turbine combustor and bluff body burner. And “M” flame has been proposed as the portent for predicting lean blowout of gas turbine combustor. Effects of flow velocity, air temperature, droplet averaged-diameter, and flow distribution between swirlers and primary holes on the LBO limit of gas turbine combustor have been researched by use of Feature-Parameter-Criterion in this paper. The effects of fuel air mixture velocity and different structures on bluff body LBO limit have also been analyzed in the present work by use of FPC. The results show that the simulation of LBO limit based on FPC is in good agreement with the experiment data (the errors are about 5%) and this method is reliable for engineering applications.

Highlights

Gas turbine is one of the most important fluid machineries in the engineering field, and bluff body burner is widely used in engine combustors to stabilize flames [1]
The results show that the simulation of lean blowout (LBO) limit based on FPC is in good agreement with the experiment data and this method is reliable for engineering applications
“M” flame, and some effect factors on lean blowout of combustor of gas turbine have been discussed in this paper

Summary

Introduction

Gas turbine is one of the most important fluid machineries in the engineering field, and bluff body burner is widely used in engine combustors to stabilize flames [1]. Numerical methods provide a reasonable approach for combustor performance prediction, heat and mass transfer process, chemical reaction recurrence, and transient response [3, 4]. For lean blowout limit predicting, advanced method should be used to match up with RANS approach. On predicting lean blowout in gas turbine combustor, there are three main methods at present: experimental research method, empirical formula method, and numerical simulation method. Most of researches did not propose appropriate criterion for predicting lean blowout limit. A new method named Feature-Parameter-Criterion (FPC) for predicting LBO limit of gas turbine combustor and bluff body burner has been put forward in this paper. Comparison between numerical simulation results and experimental data has been made to test and verify the accuracy of Feature-Parameter-Criterion

Geometry and Mathematical Models

Validations of Mathematical Models

Validations of Turbulence Combustion Model

Feature-Parameter-Criterion

Results and Analysis

Conclusion