2000 Fiscal Year Final Research Report Summary
Experimental and Numerical Study on NOx reduction in a Swirl Burner
| Project/Area Number |
11450378
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B).
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Aerospace engineering
|
|---|
| Research Institution | KYUSHU UNIVERSITY |
|---|
Principal Investigator |
YAMASAKI Nobuhiko KYUSHU UNIVERSITY, Faculty of Engineering, Prof., 工学研究院, 教授 (70166635)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
INOKUCHI Yuzo KYUSHU UNIVERSITY, Faculty of Engineering, R.A., 工学研究院, 助手 (30274509)
NAMBA Masanobu Sojyo Univ., Prof., 工学部, 教授 (50037735)
|
|---|
| Project Period (FY) |
1999 – 2000
|
| Keywords | Gas Turbine Engine / Swirl Burner / NOx reduction / Diffusion Flame / LES / Gas Chromatograph / Thermocouple |
|---|
| Research Abstract |
Hydrogen/air diffusion flame with swirl is investigated experimentally and numerically to study the effects of the swirl number on NOx reduction.
Experiments show that as the swirl number increases, (a) the local temperature in a flame decreases, and as a result (b) the local NOx concentration decreases, furthermore, (c) unburnt fuel is not observed although the local temperature decreases, and (d) small area having high temperature appears around the flame tip while in other area the local temperature decreases as the swirl number increases.
Large eddy simulations with axi-symmetric formulation and with 11 chemical species and 23-step elementary reaction model qualitatively simulate the experimental results of (a) to (c), without turbulent reaction model. Large-scale recirculation zone is appeared in the numerical simulation as the swirl number increases. The recirculation zone is not appeared when the q-w turbulence model is used.
In addition, the flow inside the model burner is simulat
… More
ed numerically, and it is found that the model burner produces negative pressure area at the burner outlet when the swirl number increases. That is, constant pressure assumption at the burner outlet is wrong when the calculation domain is taken to be downstream of the burner outlet.
Methane/air diffusion flame with swirl is also investigated experimentally. Experiments show that as the swirl number increases, (A) the local temperature in a flame decreases, however, (B) the local NOx concentration is unchanged and (C) unburnt fuel increases as the swirl number increases. The behavior of the methane air flame is quite different from those of the hydrogen/air flame.
In some cases, the numerical results with second order discretization in space and time and with Harten-Yee upwind TVD scheme show that the flame is Laminar although the experimental results show that the flame has turbulent-like behavior. This inconsistency between the simulations and the experiments appears to be overcome by applying the higher order space discretization and by applying low dissipative characteristic filter instead of applying the TVD scheme. However, details are under study now. Less
|
Research Products
(7 results)
