Abstract
For the next generation of aero-engines, manufacturers are planning to increase the overall compressor pressure ratio from existing values around 50:1 to values of 70:1. The requirement to control the tight clearances between the blade tips and the casing over all engine-operating conditions is a challenge for the engine designer attempting to minimise tipclearances
losses. Accurate prediction of the tip clearance requires an accurate prediction of the radial growth of the compressor rotor, which depends on the temperature distribution of the disc. The flow in the rotating cavities
between adjacent discs is buoyancy-driven, which creates a conjugate heat transfer problem: the disc temperature depends on the radial distribution of Nusselt number, which in turn depends on the radial distribution of disc temperature.
This paper focuses on calculating the radial growth of a simplified compressor disc in isolation from the other components. Calculations were performed using onedimensional (1D) theoretical and two-dimensional finiteelement computations (2D FEA) for overall pressure ratios
(OPR) of 50:1, 60:1 and 70:1. At each pressure ratio, calculations were conducted for five different temperature distributions; the distribution based on an experimentally validated buoyancy model was used as the datum case, and results from this were compared with those from linear, quadratic, cubic and quartic power laws.
The results show that the assumed distribution of disc temperature has a significant effect on the calculated disc growth, whereas the pressure ratio has only a relatively small effect. The good agreement between the growth calculated by the 1D theoretical model and the FEA suggests that the 1D
model should be useful for design purposes.
losses. Accurate prediction of the tip clearance requires an accurate prediction of the radial growth of the compressor rotor, which depends on the temperature distribution of the disc. The flow in the rotating cavities
between adjacent discs is buoyancy-driven, which creates a conjugate heat transfer problem: the disc temperature depends on the radial distribution of Nusselt number, which in turn depends on the radial distribution of disc temperature.
This paper focuses on calculating the radial growth of a simplified compressor disc in isolation from the other components. Calculations were performed using onedimensional (1D) theoretical and two-dimensional finiteelement computations (2D FEA) for overall pressure ratios
(OPR) of 50:1, 60:1 and 70:1. At each pressure ratio, calculations were conducted for five different temperature distributions; the distribution based on an experimentally validated buoyancy model was used as the datum case, and results from this were compared with those from linear, quadratic, cubic and quartic power laws.
The results show that the assumed distribution of disc temperature has a significant effect on the calculated disc growth, whereas the pressure ratio has only a relatively small effect. The good agreement between the growth calculated by the 1D theoretical model and the FEA suggests that the 1D
model should be useful for design purposes.
Original language | English |
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Title of host publication | Proceedings of ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition |
Publisher | American Society of Mechanical Engineers (ASME) |
Number of pages | 10 |
Publication status | Published - 17 Jun 2019 |
Event | ASME Turbo Expo 2019 - Arizona, Phoenix, USA United States Duration: 17 Jun 2019 → 21 Jun 2019 https://event.asme.org/Events/media/library/resources/turbo/Turbo-Expo-2019-Program.pdf |
Conference
Conference | ASME Turbo Expo 2019 |
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Country/Territory | USA United States |
City | Phoenix |
Period | 17/06/19 → 21/06/19 |
Internet address |