Computational prediction of a slightly heated turbulent rectangular jet discharged into a narrow channel crossflow using two different turbulence models Manabendra Pathak, Anupam Dewan * , Anoop K. Dass Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, India Available online 21 June 2006 Abstract A computational investigation of three-dimensional mean flow field resulting due to the interaction of a rectangular heated jet issuing into a narrow channel crossflow has been reported in the present paper. The jet discharge slot spans more than 55% of the crossflow channel bed, leaving a small clearance between the jet edge and sidewalls. Such flow configurations are encountered in several industrial processes such as mixing product streams, drying product streams, etc. The objective of the present work was to carry out a detailed investigation of the mean flow field and flow structure, which could not be obtained in a similar two-dimensional experimental work reported in the literature. The commercial code FLUENT 6.2.16 based on the finite volume method was used to predict the mean flow and temperature fields for the jet to crossflow velocity ratio (R) = 6. Two different turbulence models, namely, Reynolds-stress transport model (RSTM) and the standard k–e model, were used for the computations. Different terms of the Reynolds-stress transport equation were modeled based on the proposals in the literature that are appropriate for the important flow features of the present configuration. Important flow features predicted by the two models, such as the formation of different vortical structures and their effects on the flow field are discussed. Some predicted results are compared with the available experimental data reported in the literature. The predicted mean and turbulent flow properties are shown to be in good agreement with the experimental data. However, the performance of RSTM is found to be better than that of the standard k–e model. Ó 2006 Elsevier Ltd. All rights reserved. Keywords: Heated jet; Crossflow; Reynolds-stress transport model; Vortices; Turbulent mixing 1. Introduction The flow fields of jets in a crossflow are encountered in several engineering and environmental applications, for example, in cooling tower, smoke issuing from smoke- stacks, chimneys, volcanoes, thermal discharges into river, film cooling of turbine blades, fuel injection for burners, V/ STOL aircraft design, enhancement of industrial mixing and drying processes, etc. Because of its enormous applica- tions and complex fluid flow phenomenon involved, the problem has been studied extensively by several researchers both experimentally and computationally during the last 50 years. There are several review papers on this topic includ- ing those by Margason [1], Holdeman [2], Sherif and Pletcher [3] and Acharya et al. [4]. The following three con- clusions can be drawn from the literature review: (i) Most earliest studies of jet in crossflow were concerning the gross flow behaviour, such as, jet trajectory, jet penetration, jet spreading, etc. (ii) With the advancement of technology in both experimental and numerical fields, several new fea- tures of the flow field were analyzed in the literature such as the effects of velocity or momentum ratio, jet injection angle, skew angle, multiple jets, jet spacing, jet geometry, jet Reynolds number, impingements and swirl, etc. These studies extended the analysis of the flow field from the basic flow properties to the formation of different vortices, 0017-9310/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.ijheatmasstransfer.2006.05.001 * Corresponding author. Tel.: +91 361 2582656; fax: +91 361 2690762. E-mail address: adewan@iitg.ernet.in (A. Dewan). www.elsevier.com/locate/ijhmt International Journal of Heat and Mass Transfer 49 (2006) 3914–3928