Доступ предоставлен для: Guest
Главная ICHMT DL Текущий год Архив Исполнительный Комитет ICHMT

Large-Eddy Simulations of trailing-edge cutback film cooling at low blowing ratio

DOI: 10.1615/ICHMT.2009.TurbulHeatMassTransf.940
12 pages

Hayder Schneider
Institut für Thermische Strömungsmaschinen, Universität Karlsruhe (TH), Kaiserstr. 12, 76128 Karlsruhe, Germany

Dominic von Terzi
Institut für Thermische Strömungsmaschinen, Universität Karlsruhe (TH), Kaiserstr. 12, 76128 Karlsruhe, Germany

Hans-Jorg Bauer
Institut fuer Thermische Stroemungsmaschinen (ITS), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany

Аннотация

For high-pressure turbine blades, an efficient cooling of the trailing edge can be achieved by ejecting a cooling film into the flow over a cutback on the pressure side of the blade. Here, results of well-resolved Large Eddy Simulations (LES) are reported that match an existing experimental setup. A low blowing ratio M = 0:5 was chosen and compared to results for an engine-typical value of 1.1. Reasonably good agreement of mean velocity profiles and adiabatic cooling effectiveness with the experimental data was obtained. By imposing either laminar or time-dependent fully turbulent channel flow profiles within the coolant channel, the LES show that the flow regime of the coolant at ejection has a significant impact on the performance of the resulting cooling film for both blowing ratios. A surprising result is that, for the low blowing ratio, a turbulent coolant enables the cooling film to sustain a larger effectiveness farther downstream compared to a laminar coolant, whereas, for M = 1:1, the opposite is the case. This may be related to the different kinds of large coherent structures that are shown to be formed for the two cases.

ICHMT Digital Library

Bow shocks on a jet-like solid body shape. Thermal Sciences 2004, 2004. Pulsed, supersonic fuel jets - their characteristics and potential for improved diesel engine injection. PULSED, SUPERSONIC FUEL JETS - THEIR CHARACTERISTICS AND POTENTIAL FOR IMPROVED DIESEL ENGINE INJECTION
View of engine compartment components (left). Plots of temperature distributions in centreplane, forward of engine (right). CHT-04 - Advances in Computational Heat Transfer III, 2004. Devel... DEVELOPMENT AND CURRENT STATUS OF INDUSTRIAL THERMOFLUIDS CFD ANALYSIS
Pratt & Whitney's F-135 Joint Strike Fighter Engine under test in Florida is a 3600F class jet engine. TURBINE-09, 2009. Turbine airfoil leading edge stagnation aerodynamics and heat transfe... TURBINE AIRFOIL LEADING EDGE STAGNATION AERODYNAMICS AND HEAT TRANSFER - A REVIEW
Refractive index reconstructed field. (a) Second iteration. (b) Fourth iteration. Radiative Transfer - VI, 2010. Theoretical development for refractive index reconstruction from a radiative ... THEORETICAL DEVELOPMENT FOR REFRACTIVE INDEX RECONSTRUCTION FROM A RADIATIVE TRANSFER EQUATION-BASED ALGORITHM
Two inclusion test, four collimated sources. Radiative Transfer - VI, 2010. New developments in frequency domain optical tomography. Part II. Application with a L-BFGS associated to an inexa... NEW DEVELOPMENTS IN FREQUENCY DOMAIN OPTICAL TOMOGRAPHY. PART II. APPLICATION WITH A L-BFGS ASSOCIATED TO AN INEXACT LINE SEARCH