Advanced

Aerodynamic Analysis of a Humid Air Turbine Expander

Nyberg, Björn LU ; Thern, Marcus LU and Genrup, Magnus LU (2012) ASME Turbo Expo 2012: Turbine Technical Conference and Exposition In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition 3. p.217-225
Abstract
This paper presents a reduced-order through-flow expander design for the Humid Air Turbine (HAT) also called the Evaporative Gas Turbine (EvGT). The HAT cycle is an innovative gas turbine cycle that uses humid air to enhance efficiency and power output. This means that there will be a higher water vapour content in the exhaust gases than for a simple cycle. This high water content affects the design of the HAT expander. The design of a wet expander is presented and compared with the results obtained with an expander working under dry exhaust gas conditions. The study was conducted using the reduced-order turbine design tool LUAX-T, developed at Lund University, which is freely available for academic use upon request. LUAX-T allows a... (More)
This paper presents a reduced-order through-flow expander design for the Humid Air Turbine (HAT) also called the Evaporative Gas Turbine (EvGT). The HAT cycle is an innovative gas turbine cycle that uses humid air to enhance efficiency and power output. This means that there will be a higher water vapour content in the exhaust gases than for a simple cycle. This high water content affects the design of the HAT expander. The design of a wet expander is presented and compared with the results obtained with an expander working under dry exhaust gas conditions. The study was conducted using the reduced-order turbine design tool LUAX-T, developed at Lund University, which is freely available for academic use upon request. LUAX-T allows a flow-path analysis of the expander by specifying important flow-path parameters such as blade root stress and wall-hade angle. The HAT cycle enables cooling flow to the expander under different conditions and design differences for three different options are presented. The first cooling air bleeding point evaluated is the original position, where air is bled from the compressor discharge. The second position is just before the humidification tower, where the air has been cooled down to a low temperature. The third position is just after the humidification tower, where the air has been humidified thus changing its thermodynamic properties. Results in this paper shows that there is a need for an additional turbine stage in a humid expander compared to a dry expander. There are also results indicating that the compressor power can be reduced depending on which cooling strategy is used which can yield an increased total efficiency for a HAT cycle. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
in
ASME Turbo Expo 2012: Turbine Technical Conference and Exposition
volume
3
pages
9 pages
publisher
American Society Of Mechanical Engineers (ASME)
conference name
ASME Turbo Expo 2012: Turbine Technical Conference and Exposition
external identifiers
  • Scopus:84881300532
DOI
10.1115/GT2012-68996
language
English
LU publication?
yes
id
0bc27810-1d98-4ce8-b5bc-c787e2a1cec0 (old id 4276337)
date added to LUP
2014-01-30 11:19:39
date last changed
2016-10-13 04:49:30
@misc{0bc27810-1d98-4ce8-b5bc-c787e2a1cec0,
  abstract     = {This paper presents a reduced-order through-flow expander design for the Humid Air Turbine (HAT) also called the Evaporative Gas Turbine (EvGT). The HAT cycle is an innovative gas turbine cycle that uses humid air to enhance efficiency and power output. This means that there will be a higher water vapour content in the exhaust gases than for a simple cycle. This high water content affects the design of the HAT expander. The design of a wet expander is presented and compared with the results obtained with an expander working under dry exhaust gas conditions. The study was conducted using the reduced-order turbine design tool LUAX-T, developed at Lund University, which is freely available for academic use upon request. LUAX-T allows a flow-path analysis of the expander by specifying important flow-path parameters such as blade root stress and wall-hade angle. The HAT cycle enables cooling flow to the expander under different conditions and design differences for three different options are presented. The first cooling air bleeding point evaluated is the original position, where air is bled from the compressor discharge. The second position is just before the humidification tower, where the air has been cooled down to a low temperature. The third position is just after the humidification tower, where the air has been humidified thus changing its thermodynamic properties. Results in this paper shows that there is a need for an additional turbine stage in a humid expander compared to a dry expander. There are also results indicating that the compressor power can be reduced depending on which cooling strategy is used which can yield an increased total efficiency for a HAT cycle.},
  author       = {Nyberg, Björn and Thern, Marcus and Genrup, Magnus},
  language     = {eng},
  pages        = {217--225},
  publisher    = {ARRAY(0x96f08c8)},
  series       = {ASME Turbo Expo 2012: Turbine Technical Conference and Exposition},
  title        = {Aerodynamic Analysis of a Humid Air Turbine Expander},
  url          = {http://dx.doi.org/10.1115/GT2012-68996},
  volume       = {3},
  year         = {2012},
}