Log in

Login to your account

Username *
Password *
Remember Me
: 14 + 15 =

GPPS Journal Papers

Staged combustion concept for gas turbines

User Rating: 5 / 5

Star ActiveStar ActiveStar ActiveStar ActiveStar Active
 

Dieter Winkler1, Weiqun Geng 1, Geoffrey Engelbrecht 1, This email address is being protected from spambots. You need JavaScript enabled to view it. 1, Klaus Knapp 2 and Timothy Griffin 1

1 FHNW, School of Engineering, University of Applied Sciences and Arts Northwestern Switzerland, Windisch, 5210, Switzerland
2 Ansaldo Energia Switzerland Ltd., Baden, 5401, Switzerland

Abstract

Gas turbine power plants with high load flexibility are particularly suitable to compensate power fluctuations of wind and solar plants. Conventional gas turbines suffer from higher emissions at low load operation. With the objective of improving this situation a staged combustion system has been investigated. At low gas turbine load an upstream stage (first stage) provides stable combustion at low emissions while at higher loads the downstream stage (second stage) is started to supplement the power. Three injection geometries have been studied by means of computational fluid dynamics (CFD) simulations and atmospheric tests. The investigated geometries were a simple annular gap, a jet-in-cross-flow configuration and a lobe mixer. With CFD simulations the quality of mixing of second stage fresh gas with first stage exhaust gas was assessed. The lobe mixer showed the best mixing quality and hence was expected to also be the best variant in terms of combustion. However atmospheric combustion tests showed lower emissions for the jet-in-cross-flow configuration. Comparing flame photos in the visible and ultraviolet (UV) range suggest that the flame might be lifted off for the lobe mixer, leading to insufficient time for carbon monoxide (CO) burnout. CFD analysis of turbulent flame speed, turbulence and strain rates support the hypotheses of lifted off flame. Overall the staged concept was found to show very promising results not only with natural gas but also with natural gas enriched with propane or hydrogen. The investigations showed that apart from having an efficient and compact mixing of the two stages it is also very important to design the flow field such that the second flame can be anchored properly in order to achieve compact flames with sufficient time for CO burnout.

Read Full Paper (Visit Journal Website)

Global Power and Propulsion Society (GPPS)

Address

Address :

Landis + Gyr-Strasse 1, 6300 Zug, Switzerland

Tel. :

+41 44 632 50 72

Recent tweets

To minimize the potential impact of technical difficulties associated with a registration "bottleneck" occurring ju… https://t.co/z3cqVSd6nV
Vote today for your GPPS 2020 Awards candidate. Our new online form is now available. https://t.co/9axXsiXfwt
Register your place at the first GPPS Chania20 Online Conference. We look forward to hearing the latest leading-edg… https://t.co/gQLlKqkJ9E