首页   按字顺浏览 期刊浏览 卷期浏览 Stochastic model theory for coherent turbulent structures in circular jets
Stochastic model theory for coherent turbulent structures in circular jets

 

作者: Peter Plaschko,  

 

期刊: Physics of Fluids(00319171)  (AIP Available online 1981)
卷期: Volume 24, issue 2  

页码: 187-193

 

ISSN:0031-9171

 

年代: 1981

 

DOI:10.1063/1.863364

 

出版商: AIP

 

数据来源: AIP

 

摘要:

A stochastic model based on a linearized theory is developed. It is assumed that the large scale structure of the turbulence is created randomly at the jet orifice and that its subsequent convection downstream may be described in terms of quantities predicted by a linearized inviscid stability theory for slowly diverging flows. The process of the generation of turbulence is modeled by the imposition of a stochastic initial condition for the corresponding stability problem. The application of this condition secures the homogeneity of mean values of the turbulent quantities with respect to the angular coordinate; the contribution of each spiral mode is then proportional to a certain spectral function, the latter being an unknown function within the framework of the present study. Since experiments have shown that the turbulence of jets is far from being adequately represented by white noise conditions, the spectral functions must be determined by fitting to experimental data. It is shown that the model is capable of predicting the experimental trends for circumferential and radial coherence functions fairly well. However, complications arise with respect to the axial coherence functions and an attempt is made to alleviate the difficulties by either a cutoff assumption or by a process of continuation of the inviscid quantities.

 

点击下载:  PDF (512KB)



返 回