The University of Southampton
University of Southampton Institutional Repository

Compressible direct numerical simulation of low-pressure turbines: part I - methodology

Compressible direct numerical simulation of low-pressure turbines: part I - methodology
Compressible direct numerical simulation of low-pressure turbines: part I - methodology
Modern low pressure turbines (LPT) feature high pressure ratios and moderate Mach and Reynolds numbers, increasing the possibility of laminar boundary-layer separation on the blades. Upstream disturbances including background turbulence and incoming wakes have a profound effect on the behavior of separation bubbles and the type/location of laminar-turbulent transition and therefore need to be considered in LPT design. URANS are often found inadequate to resolve the complex wake dynamics and impact of these environmental parameters on the boundary layers and may not drive the design to the best aerodynamic efficiency. LES can partly improve the accuracy, but has difficulties in predicting boundary layer transition and capturing the delay of laminar separation with varying inlet turbulence levels. Direct Numerical Simulation (DNS) is able to overcome these limitations but has to date been considered too computationally expensive. Here a novel compressible DNS code is presented and validated, promising to make DNS practical for LPT studies. Also, the sensitivity of wake loss coefficient with respect to freestream turbulence levels below 1% is discussed.
0889-504X
Sandberg, R.D.
41d03f60-5d12-4f2d-a40a-8ff89ef01cfa
Pichler, R.
5150d90a-340b-4ebd-aac0-3d4c977e996b
Chen, L.
586c0d55-dc72-49c0-a4fa-31df7000ce18
Johnstone, R.
8ac02aa2-776b-4f80-b44d-1a5cf8682f21
Michelassi, V.
b596e629-2057-4a5b-afbc-24f891a61638
Sandberg, R.D.
41d03f60-5d12-4f2d-a40a-8ff89ef01cfa
Pichler, R.
5150d90a-340b-4ebd-aac0-3d4c977e996b
Chen, L.
586c0d55-dc72-49c0-a4fa-31df7000ce18
Johnstone, R.
8ac02aa2-776b-4f80-b44d-1a5cf8682f21
Michelassi, V.
b596e629-2057-4a5b-afbc-24f891a61638

Sandberg, R.D., Pichler, R., Chen, L., Johnstone, R. and Michelassi, V. (2015) Compressible direct numerical simulation of low-pressure turbines: part I - methodology. Journal of Turbomachinery. (doi:10.1115/1.4028731).

Record type: Article

Abstract

Modern low pressure turbines (LPT) feature high pressure ratios and moderate Mach and Reynolds numbers, increasing the possibility of laminar boundary-layer separation on the blades. Upstream disturbances including background turbulence and incoming wakes have a profound effect on the behavior of separation bubbles and the type/location of laminar-turbulent transition and therefore need to be considered in LPT design. URANS are often found inadequate to resolve the complex wake dynamics and impact of these environmental parameters on the boundary layers and may not drive the design to the best aerodynamic efficiency. LES can partly improve the accuracy, but has difficulties in predicting boundary layer transition and capturing the delay of laminar separation with varying inlet turbulence levels. Direct Numerical Simulation (DNS) is able to overcome these limitations but has to date been considered too computationally expensive. Here a novel compressible DNS code is presented and validated, promising to make DNS practical for LPT studies. Also, the sensitivity of wake loss coefficient with respect to freestream turbulence levels below 1% is discussed.

Full text not available from this repository.

More information

e-pub ahead of print date: 26 November 2014
Published date: 1 May 2015
Organisations: Aeronautics, Astronautics & Comp. Eng, Aerodynamics & Flight Mechanics Group, Faculty of Engineering and the Environment

Identifiers

Local EPrints ID: 370727
URI: http://eprints.soton.ac.uk/id/eprint/370727
ISSN: 0889-504X
PURE UUID: a7f1325d-6e84-4038-818d-b21a15216567
ORCID for R.D. Sandberg: ORCID iD orcid.org/0000-0001-5199-3944

Catalogue record

Date deposited: 05 Nov 2014 11:41
Last modified: 09 Sep 2019 18:42

Export record

Altmetrics

Contributors

Author: R.D. Sandberg ORCID iD
Author: R. Pichler
Author: L. Chen
Author: R. Johnstone
Author: V. Michelassi

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×