Turbulent mixing in T-junctions: The role of the temperature as an active scalar

被引:28
作者
Georgiou, Michail [1 ]
Papalexandris, Miltiadis V. [1 ]
机构
[1] Catholic Univ Louvain, Inst Mech Mat & Civil Engn, B-1348 Louvain La Neuve, Belgium
关键词
Large Eddy Simulation; Separated flows; Thermal stratification; Thermal fatigue; Turbulent mixing; T-junction; LARGE-EDDY SIMULATION; DIRECT NUMERICAL-SIMULATION; CROSS-FLOW; CHANNEL FLOW; THERMAL FATIGUE; HEAT-TRANSFER; TEE; JETS; FLUCTUATIONS; GRADIENTS;
D O I
10.1016/j.ijheatmasstransfer.2017.08.081
中图分类号
O414.1 [热力学];
学科分类号
摘要
In this paper we present a detailed study of turbulent mixing between a cold crossflow and a hot incoming jet in a T-junction. Our study is based on wall-resolved and experimentally validated Large Eddy Simulations (LES) without invoking the Boussinesq approximation regarding density variations. Emphasis is placed on the role of the temperature as an active scalar and the impact of thermal stratification on the emerging structures in the flow field. Herein we discuss in detail the main features of the flow, such as the shear layer between the two streams, the regions of flow acceleration due to the Venturi effect, the recirculation regions, and the thermal mixing downstream the reattachment point of the flow. We also elaborate on the first and second-order statistics of flow quantities, including the turbulent heat fluxes, and on the near-wall behaviour of the streamwise velocity component. Our numerical predictions compare favourably with existing experimental measurements, as regards both the temperature field and the turbulent heat fluxes. Our study also includes a spectral analysis of the temperature signal at selected locations near the solid boundaries, which is helpful for assessing the risk of thermal fatigue at the walls of the T-junction. (C) 2017 Elsevier Ltd. All rights reserved.
引用
收藏
页码:793 / 809
页数:17
相关论文
共 46 条
[1]   EXPERIMENTAL INVESTIGATION OF JETS IN A CROSS-FLOW [J].
ANDREOPOULOS, J ;
RODI, W .
JOURNAL OF FLUID MECHANICS, 1984, 138 (JAN) :93-127
[2]  
[Anonymous], 2000, INT C FAT REACT COMP
[3]   An experimental investigation of a highly accelerated turbulent boundary layer [J].
Bourassa, C. ;
Thomas, F. O. .
JOURNAL OF FLUID MECHANICS, 2009, 634 :359-404
[4]   Hydro-thermal-mechanical analysis of thermal fatigue in a mixing tee [J].
Chapuliot, S ;
Gourdin, C ;
Payen, T ;
Magnaud, JP ;
Monavon, A .
NUCLEAR ENGINEERING AND DESIGN, 2005, 235 (05) :575-596
[5]   An experimental study of heat transfer in a two-dimensional T-junction operating at a low momentum flux ratio [J].
de Tilly, A. ;
Sousa, J. M. M. .
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, 2008, 51 (3-4) :941-947
[6]  
FAVRE A, 1983, PHYS FLUIDS, V26, P2851, DOI 10.1063/1.864049
[7]   Highly resolved large-eddy simulation of separated flow in a channel with streamwise periodic constrictions [J].
Fröhlich, J ;
Mellen, CP ;
Rodi, W ;
Temmerman, L ;
Leschziner, MA .
JOURNAL OF FLUID MECHANICS, 2005, 526 :19-66
[8]  
Fukushima Naoya, 2003, 6 ASME JSME THERM EN
[9]  
Gelineau O., 2001, T 16 INT C STRUCTURA, V1311, P1
[10]   Numerical study of turbulent flow in a rectangular T-junction [J].
Georgiou, Michail ;
Papalexandris, Miltiadis V. .
PHYSICS OF FLUIDS, 2017, 29 (06)