Details
| Original language | English |
|---|---|
| Pages (from-to) | 314-320 |
| Number of pages | 7 |
| Journal | Journal of thermal science |
| Volume | 14 |
| Issue number | 4 |
| Publication status | Published - Dec 2005 |
Abstract
The increasing use of gas turbines in combined cycle power plants together with the high amount of kinetic energy in modern gas turbine exhaust flows focuses attention on the design of gas turbine diffusers as the connecting part between the Brayton/Joule and the Rankine parts of the combined cycle. A scale model of a typical gas turbine exhaust diffuser is investigated experimentally. The test rig consists of a radial type, variable swirl generator which provides the exhaust flow corresponding to different gas turbine operating conditions. Static pressure measurements are carried out along the outer diffuser walls and along the hub of the annular part and along the centerline of the conical diffuser. Velocity distributions at several axial positions in the annular and conical diffuser have been measured using a Laser Doppler Velocimeter (LDV). Pressure recovery coefficients and velocity profiles are depicted as a function of diffuser length for several combinations of swirl strength, tip flow and strut geometries. The diffuser without struts achieved a higher pressure recovery than the diffuser with struts at all swirl angle settings. The diffuser with cylindrical struts achieved a higher pressure recovery than the diffuser with profiled struts at all swirl angle settings. Inlet flows with swirl angles over 18° affected the pressure recovery negatively for all strut configurations.
Keywords
- Gas turbine exhaust diffuser, Pressure recovery coefficient, Struts, Swirl
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Condensed Matter Physics
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: Journal of thermal science, Vol. 14, No. 4, 12.2005, p. 314-320.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Interaction between Struts and Swirl Flow in Gas Turbine Exhaust Diffusers
AU - Pietrasch, Roman Z.
AU - Seume, Joerg R.
N1 - Funding information: The research on which this paper is based was sponsored by the DFG (Deutsche Forschungsgesellschaft') and carried out at the Turbomachinery Laboratory, University of Hannover, Germany. The authors would like to thank Sebastian Kanzer and Bastian Schreyer for their helpfully and frequently input and guidance. Special thanks to Simon Kneser and Kathrin Henke for their effort in design, programming, and measuring. Additionally, thanks to Benno Fuhrmann for his perfectly manufacturing of the turnable hub
PY - 2005/12
Y1 - 2005/12
N2 - The increasing use of gas turbines in combined cycle power plants together with the high amount of kinetic energy in modern gas turbine exhaust flows focuses attention on the design of gas turbine diffusers as the connecting part between the Brayton/Joule and the Rankine parts of the combined cycle. A scale model of a typical gas turbine exhaust diffuser is investigated experimentally. The test rig consists of a radial type, variable swirl generator which provides the exhaust flow corresponding to different gas turbine operating conditions. Static pressure measurements are carried out along the outer diffuser walls and along the hub of the annular part and along the centerline of the conical diffuser. Velocity distributions at several axial positions in the annular and conical diffuser have been measured using a Laser Doppler Velocimeter (LDV). Pressure recovery coefficients and velocity profiles are depicted as a function of diffuser length for several combinations of swirl strength, tip flow and strut geometries. The diffuser without struts achieved a higher pressure recovery than the diffuser with struts at all swirl angle settings. The diffuser with cylindrical struts achieved a higher pressure recovery than the diffuser with profiled struts at all swirl angle settings. Inlet flows with swirl angles over 18° affected the pressure recovery negatively for all strut configurations.
AB - The increasing use of gas turbines in combined cycle power plants together with the high amount of kinetic energy in modern gas turbine exhaust flows focuses attention on the design of gas turbine diffusers as the connecting part between the Brayton/Joule and the Rankine parts of the combined cycle. A scale model of a typical gas turbine exhaust diffuser is investigated experimentally. The test rig consists of a radial type, variable swirl generator which provides the exhaust flow corresponding to different gas turbine operating conditions. Static pressure measurements are carried out along the outer diffuser walls and along the hub of the annular part and along the centerline of the conical diffuser. Velocity distributions at several axial positions in the annular and conical diffuser have been measured using a Laser Doppler Velocimeter (LDV). Pressure recovery coefficients and velocity profiles are depicted as a function of diffuser length for several combinations of swirl strength, tip flow and strut geometries. The diffuser without struts achieved a higher pressure recovery than the diffuser with struts at all swirl angle settings. The diffuser with cylindrical struts achieved a higher pressure recovery than the diffuser with profiled struts at all swirl angle settings. Inlet flows with swirl angles over 18° affected the pressure recovery negatively for all strut configurations.
KW - Gas turbine exhaust diffuser
KW - Pressure recovery coefficient
KW - Struts
KW - Swirl
UR - http://www.scopus.com/inward/record.url?scp=30044435029&partnerID=8YFLogxK
U2 - 10.1007/s11630-005-0051-x
DO - 10.1007/s11630-005-0051-x
M3 - Article
AN - SCOPUS:30044435029
VL - 14
SP - 314
EP - 320
JO - Journal of thermal science
JF - Journal of thermal science
SN - 1003-2169
IS - 4
ER -