Abstract
The buoyancy-induced flow and heat transfer inside the compressor rotors of gas-turbine engines affects the stresses and radial growth of the compressor disks, and it also causes a temperature rise in the axial throughflow of cooling air through the center of the disks. In turn, the radial growth of the disks affects the radial clearance between the rotating compressor blades and the surrounding stationary casing. The calculation of this clearance is extremely important, particularly in aeroengines where the increase in pressure ratios results in a decrease in the size of the blades. In this paper, a published theoretical model - based on buoyancy-induced laminar Ekman-layer flow on the rotating disks - is extended to include laminar free convection from the compressor shroud and forced convection between the bore of the disks and the axial throughflow. The predicted heat transfer from these three surfaces is then used to calculate the temperature rise of the throughflow. The predicted temperatures and Nusselt numbers are compared with measurements made in a multicavity compressor rig, and mainly good agreement is achieved for a range of Rossby, Reynolds, and Grashof numbers representative of those found in aeroengine compressors. Owing to compressibility effects in the fluid core between the disks - and as previously predicted - increasing rotational speed can result in an increase in the core temperature and a consequent decrease in the Nusselt numbers from the disks and shroud.
| Original language | English |
|---|---|
| Article number | 071902 |
| Number of pages | 9 |
| Journal | Journal of Engineering for Gas Turbines and Power: Transactions of the ASME |
| Volume | 140 |
| Issue number | 7 |
| Early online date | 15 Dec 2017 |
| DOIs | |
| Publication status | Published - 1 Jul 2018 |
Fingerprint
ASJC Scopus subject areas
- Nuclear Energy and Engineering
- Fuel Technology
- Aerospace Engineering
- Energy Engineering and Power Technology
- Mechanical Engineering
Cite this
Buoyancy-Induced Flow and Heat Transfer in Compressor Rotors. / Tang, Hui; Puttock-Brown, Mark R.; Owen, John M.
In: Journal of Engineering for Gas Turbines and Power: Transactions of the ASME, Vol. 140, No. 7, 071902, 01.07.2018.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Buoyancy-Induced Flow and Heat Transfer in Compressor Rotors
AU - Tang, Hui
AU - Puttock-Brown, Mark R.
AU - Owen, John M.
PY - 2018/7/1
Y1 - 2018/7/1
N2 - The buoyancy-induced flow and heat transfer inside the compressor rotors of gas-turbine engines affects the stresses and radial growth of the compressor disks, and it also causes a temperature rise in the axial throughflow of cooling air through the center of the disks. In turn, the radial growth of the disks affects the radial clearance between the rotating compressor blades and the surrounding stationary casing. The calculation of this clearance is extremely important, particularly in aeroengines where the increase in pressure ratios results in a decrease in the size of the blades. In this paper, a published theoretical model - based on buoyancy-induced laminar Ekman-layer flow on the rotating disks - is extended to include laminar free convection from the compressor shroud and forced convection between the bore of the disks and the axial throughflow. The predicted heat transfer from these three surfaces is then used to calculate the temperature rise of the throughflow. The predicted temperatures and Nusselt numbers are compared with measurements made in a multicavity compressor rig, and mainly good agreement is achieved for a range of Rossby, Reynolds, and Grashof numbers representative of those found in aeroengine compressors. Owing to compressibility effects in the fluid core between the disks - and as previously predicted - increasing rotational speed can result in an increase in the core temperature and a consequent decrease in the Nusselt numbers from the disks and shroud.
AB - The buoyancy-induced flow and heat transfer inside the compressor rotors of gas-turbine engines affects the stresses and radial growth of the compressor disks, and it also causes a temperature rise in the axial throughflow of cooling air through the center of the disks. In turn, the radial growth of the disks affects the radial clearance between the rotating compressor blades and the surrounding stationary casing. The calculation of this clearance is extremely important, particularly in aeroengines where the increase in pressure ratios results in a decrease in the size of the blades. In this paper, a published theoretical model - based on buoyancy-induced laminar Ekman-layer flow on the rotating disks - is extended to include laminar free convection from the compressor shroud and forced convection between the bore of the disks and the axial throughflow. The predicted heat transfer from these three surfaces is then used to calculate the temperature rise of the throughflow. The predicted temperatures and Nusselt numbers are compared with measurements made in a multicavity compressor rig, and mainly good agreement is achieved for a range of Rossby, Reynolds, and Grashof numbers representative of those found in aeroengine compressors. Owing to compressibility effects in the fluid core between the disks - and as previously predicted - increasing rotational speed can result in an increase in the core temperature and a consequent decrease in the Nusselt numbers from the disks and shroud.
UR - http://www.scopus.com/inward/record.url?scp=85046639137&partnerID=8YFLogxK
U2 - 10.1115/1.4038756
DO - 10.1115/1.4038756
M3 - Article
VL - 140
JO - Journal of Engineering for Gas Turbines and Power: Transactions of the ASME
JF - Journal of Engineering for Gas Turbines and Power: Transactions of the ASME
SN - 0742-4795
IS - 7
M1 - 071902
ER -